Erect to marginally decumbent or procumbent, sometimes colonial herbs 0.5–2(-4) dm tall from a fibrous root system that bears erect, ascending, sometimes horizontal (rhizomatous) subsurface shoots that bear or terminate in stems. Stem internodes longer or shorter than the subtending leaves, usually puberulent-strigulose with bent to decurved, thickish trichomes or with more spreading, rather crisped trichomes. Leaves linear, linear-oblanceolate to oblong-oblanceolate, 7–40 mm long, 1–7 mm wide, acute to rounded at the apex, cuneate with margins forming narrow wings along the short petiole at the base, the margins entire to erose, the leaf-blades thin and flat or thickened and more conduplicate, olive green to grayish, sparsely strigulose with short antrorsely curved or bent hairs or longer spreading hairs throughout or the hairs lacking in the intercostal areas on the lower surface. Flowers 1–3 (-7) per leaf axil in compressed dichasial cymes; peduncles 0.2–1 (-2) mm long; paired bracts leafy, usually linear-oblanceolate, acute, 0.5–2.5 cm long, vestitured as leaves; calyces 8.5–17 mm long, glabrous or vestitured, lobes 5, puberulent, hispid to setose along the margins and midrib with hairs 0.1–0.3(-0.5) mm long. Corollas lavender to purplish, sometimes with whitish veins and some times marked with red in the lower throat, 9–24 mm long (dry), the tube cylindrical, 3.2–10 mm long, throat campanulate, 3.5–7 mm long, lower 3 lobes slightly decurved, oblong-obovate, rounded to emarginate at the tips, the upper 2 lobes ascending, rounded; anthers 4, glabrous, purplish, drying yellowish, 1.2–1.7 mm long, with or without a terminal apiculation, basal spurs 0.15 mm long; longer free filaments 2.8–4 mm long, the shorter free filaments 1.5–3.2 mm long, the style 7–14 mm long, exserted beyond the anthers and usually extending from the throat. Fruits 8–10 mm long; seeds 2–4, about 2.5 mm long.

As recognized here, Dyschoriste schiedeana is a highly variable taxon consisting of four widespread varieties. The four taxa can be separated by the following key.

Dyschoriste schiedeana (Nees) Kuntze Rev. Gen. PL 2: 486. 1891; Calophanes schiedeanus Nees in DC. Prodr. 11: 111. 1847. Type. MEXICO. Veracruz: prope Jalapam (Xalapa), Schiede 122 (holotype: HAL!)

Dyschoriste lloydii Kobuski, Ann. Missouri Bot. Gard 15:46. 1928. Type. MEXICO. Zacatecas: Hacienda de Cedros, 1908, F. E. Lloyd 199 (holotype: US!)

Erect to erect-ascending herbs 0.5–2(-4) dm tall, sometimes with the marginal stems decumbent-procumbent, or the stems produced solitary or in multistemmed clusters along rhizomes, or the plants essentially non-rhizomatous, bushy, with a cluster of fibrous roots; internodes (3.5-) 10–25(-50) mm long, longer or shorter than the subtending leaves, usually puberulent-strigulose with bent to curved, short thickish hairs 0.06–0.2 mm long, or with spreading, rather crisped hairs to 0.3(-5) mm long. Leaves linear-oblanceolate to oblong-oblanceolate, (7-) 12–25 (-40) mm long, (1-)2–5(-7) mm wide, acute, obtuse, apiculate to rounded at apex, cuneate at base, the margins entire, occasionally erose, the leaf-blades thin, flat or thickened and variously folded along the lower midrib, sometimes nearly cylindrical, straight and erect or arching outward, sparsely strigulose with antrorsely curved or bent hairs 0.06–0.15 along the upper surface, basal margins and main veins of the lower surface or the hairs more uniformly scattered on both surfaces, or with more conspicuous, tapering, rather crinkled hairs to 0.3(-0.5) mm long throughout; petioles 0.5–2.5 mm long, channeled, winged; the leaves and bracts yellowish to olive-green; paired bracts foliaceous, usually linear-oblanceolate, acute, 0.5–2.5 cm long. Flowers with calyces 8.5–12 mm long, glabrous or variously vestitured, the lobes puberulent, strigulose along the margins and midrib with hairs 0.1–0.3(-0.5) mm long, the longer hairs sometimes slightly setose; corollas (9.2-) 12–16(-18) mm long (dry), the tube cylindrical 3.2–7 mm long, throat ampliate, 3.5–5.5 mm long, the 2 upper lobes upcurved, 2.2–4 mm long. 1.7–3.5 mm wide, the lower 3 lobes slightly decurved, the medial lobe oblong-obovate, 3.6–4.5 mm long, 3–4.2 mm wide, rounded to emarginate at the tip. Fruits 8–10 mm long.

Distribution (Fig. 2) and Habitat. Dyschoriste schiedeana var. schiedeana occurs in caliche, rocky, gravelly, clay, flats, slopes, rocky ledges, limestone and gypseous areas, in grasslands, arid scrub, oak-pine, Yucca or juniper woodlands; central Veracruz to eastern San Luis Potosi, western Tamaulipas, Hidalgo, Queretaro, through the Sierra Madre Oriental in Nuevo Leon to southeast Coahuila from 1000 to 2400 m elevation; flowering from May through November.

Dyschoriste schiedeana var. schiedeana, as recognized here, is a very variable taxon characterized by its erect, ascending stems, sometimes also with marginal decumbent stems that develop from a fasciculate root system that may produce broad-based, rather bushy individual plants or occasionally colonial groups of bushy or erect, single-stemmed plants scattered along a rhizome. Leaves are mostly linear-oblanceolate, yellowish green or olive green, sparsely or closely vestitured, thin or thick in texture, flat or variously conduplicate, sparsely pubescent throughout or more commonly only along the veins of the lower surface with the intercostal areas glabrous. Leaf vestiture many be short or long and coarse and tending to fall from older leaves when longer. Corollas are generally small (9.2-) 12–16(-18) mm in total length. This variety has several different morphotypes that are discussed below.

Type 1: Rhizomatous plants producing a series of separate, erect, long stems with large leaves usually separated by longer internodes (Fig. 1A). They have thin, flat, yellow-green, spatulate leaves 8–25 mm long, 1.5–5 mm wide, with rather coarse hairs to 0.5(-0.7) mm long scattered on the upper leaf surface, but usually restricted to the veins and margins on the lower surface though scattered hairs may occur on both surfaces (Fig. 1B). Corollas are 11–15 mm long, calyces 6.5–8 mm long with tubes 2–2.2 mm long and the sepal margins have scattered slender hairs and some setae to 0.5 mm long (Fig. 1C). These plants occur from the type region of the species near Jalapa, Veracruz, to eastern San Luis Potosí and through Nuevo León into Coahuila and in Flidalgo. It is not possible to separate these tall, slender plants from the more common low, bushy type plants discussed below, as the two types intergrade completely.

Representative specimens examined: MEXICO. Coahuila: Lirios, E of Saltillo, 10–13 Jul 1880, Palmer 1010 (GH, MO, US). Nuevo León: Chipinque Park, SW of Monterrey, 11 Jun 1978, Poole & Watson 1389 (TEX); Mpio. Aramberri, Cerro Grande, 6 Jul 1986, Hinton 18992 (TEX); Santa Gertrudis near Dr. Arroyo, 20 Jul 1993, Hinton 23048 (TEX); 15 mi E of San Rafael off Hwy 57, 25°03′N,100$deg;26′W, 22–23 Jul 1977, Wells & Nesom 119 (TEX). San Luis Potosí: San Dieguito near Cd. Valles, 13–16 Jun 1904, Palmer 99 (GH, US). Veracruz: Mpio. Dos Ríos, Cerro Gordo, 3 Jul 1973, Ventura 8517 (ARIZ, LL); Mpio. Xalapa, Cerro Colorado, 27 Mar 1974, Ventura 9775 (LL). Hidalgo: Mpio. Jacala, Pine woods, 1 Jul 1939, Chase 7259 (F); Cupresus forest, along hwy 85, 7.4 mi SW of Jacala, 15 Aug 1984, Daniel & Baker 3731 (CAS).

Type 2: Bushy low plants to 1 dm tall with many erect-ascending central stems from an underground rootstock, with thin, rather broad, uniformly vestitured leaves and short internodes. They may have procumbent marginal stems (Fig. 1D). Some collections show rhizomes connecting separate plants. This is the most commonly encountered form of Dyschoriste schiedeana var. schiedeana and would include the type of the species. The leaves are crowded, moderately thin, closely pubescent-puberulent throughout or the hairs may be absent or diminish in the intercostal areas of the lower surface. Leaves are mostly narrowly oblanceolate or somewhat obovate, but they may appear narrower as they are variously conduplicate, and sometimes they are folded only above the petiole, not near the apex (Fig. 1E). Corollas range from 9–18 mm in length.

The type of Dyschoriste lloydii Kobuski from Hacienda de Cedros in northern Zacatecas also fits into this group. The type plant is short, multistemmed with erect-ascending stems and glabrous intercostal areas on the lower leaf surface. Other specimens from that general area (Shreve 9399, Stanford et al. 492) are similar, but all have decumbent marginal stems. The presence of marginal procumbent stems may originate from introgression with Dyschoriste schiedeana var. prostrata.

Representative specimens examined: [Those with leaves hairy throughout are preceded with an (H) those with decumbent-procumbent stems with a (D)]. MEXICO. Coahuila: (H-D) Fraile, 59 km S of Saltillo, 10 Jul 1941, Stanford, Retherford & Northcraft 272 (ARIZ, GH, MO, NY); (D) 2–16 mi E of Carneros Pass to Hedionda Grande, 2 May 1955, Correll and Johnston 21343 (LL); (H-D) 11 km NE of Jimulco, 28 Jun 1941, Stanford, Retherford & Northcraft 24 (ARIZ, GH, MO, NY). San Luis Potosí: (D) Mpio. Cd. del Maíz, 15.6 mi SW of Jet. with hwy 80 at San Tiburcio, 14 Sep 1988, Nesom & Wells 6671 (TEX); (H-D) Charcas, Jul-Aug 1934, Lundell 5049 (LL); (H-D) Valley Río Verde, 14–15 Sep 1954, Sohns 1255 (US-2). Zacatecas: (D) Base of Pico Teyra, 12 Sep 1939, Shreve 9399 (ARIZ, GH); (D) 15 km W of Concepción del Oro, Coah.-Zac. border, 19 Jul 1941, Stanford, Retherford & Northcraft 492 (ARIZ, GH, MO, NY). Nuevo León: (H) Mpio. Aramberri, La Escondida to Aramberri, 23 Oct 1993, Hinton 32728 (TEX); (D) 29 mi W of Galeana, 20 Nov 1958, Rollins & Tryon 58177 (LL); (with rhizomes) 3 mi above Iturbide, rd to Galeana, 18 May 1949, McVaugh 10565 (LL, NY, US). Querétaro: near Querétaro, 20–23 Aug 1906, Rose 11148 (NY). Hidalgo: (D) NE of Jalaca, 16 Jul 1947, Moore 3412 (GH); (D) Mpio. Jacala, Rocky mt side, 26 Jun 1939, Chase 7171 (F, GH).

Type 3: Small, bushy, multistemmed plants 0.5–1 dm tall, with thick, crowded, narrowly folded leaves (Fig. 1F, G). The leaves are linear-oblanceolate, 8–12 mm long, 1–2 mm wide, conduplicate and in some collections are nearly cylindrical due to folding (Fig. 1G). They may or may not have marginal decumbent-procumbent stems. These plants occur scattered throughout the range of the taxon and appear to represent a more xeric morph of exposed habitats.

Representative specimens examined: MEXICO. Tamaulipas: Near Miquihuana 23°42′N, 99°45′W, 8 Aug 1941, Stanford, Retherford & Northcraft 759 (ARIZ, GH, MO, NY); 5 mi NE of Jaumave, 23°29′N, 99°21′W, 1 Aug 1976, Webster & Armbruster 20550 (TEX). Nuevo León: 3 km N of Galeana, in gypsum, 26 Jul 1993, Turner 93–159 (TEX); near Ojo de Agua, foot of Cerro Potosí, 15 Jul 1945, Sharp 45725 (GH, NY, US). Coahuila: 17 mi S of Saltillo, 1.1 mi N of turnoff to San Antonio de las Alazanas, 24 Jul 1985, Ginsbargetal 194 (TEX).

In addition to the above, there are plants with erect-ascending central stems and well developed lateral procumbent stems with crowded, thin leaves and colonial plants consisting of bushy plants interconnected by subterranean rhizomes.

It is not actually known how much of the variation present in Dyschoriste schiedeana var. schiedeana comes through introgression with other taxa within the species. The uniform leaf vestiture may well be derived from var. cinerascens; it is strongly suspected that the tendency to produce lateral decumbent stems is derived from vars. prostrata and decumbens. Plants similar to var. schiedeana, but with larger leaves, occur scattered throughout the range of var. cinerascens, as far north as trans-Pecos Texas. Whether these are truly var. schiedeana or a more mesic phase of var. cinerascens is not known. Likewise, plants with the characteristic growth habit of var. cinerascens occur scattered well within the range of var. schiedeana in San Luis Potosí and Nuevo LeÁn. This great overlap of characters make recognition of the two taxa at the species level impossible and adds to the difficulty of understanding this group.

The most difficult group of specimens encountered in this complex consists of overgrown erect to broadly spreading plants with long internodes and large, green to gray green, thin leaves to 25–43 mm long, 3–9 mm wide, with entire or erose margins and long, rather slender petioles. None of the specimens (see listing below) has many flowers and some have no flowers or fruit. The vestiture on the stem is moderately dense, that of the leaves is variable, but generally sparse on both surfaces. These plants occur widely scattered throughout the range of all the varieties of Dyschoriste schiedeana. It is my contention that these collections do not represent a taxon but are either shade forms or water-rich “seep” specimens from arroyo margins, seeps, or stock ponds with uncharacteristic strong vegetative growth. They appear to be preferentially collected when little else is in flower.

Representative specimens examined: MEXICO. Chihuahua: Mesa N of La Junta, 10–19 Oct 1935, LeSueur 422 (F, MO, TEX) = var. decumbens. Coahuila: Sierra la Paila, 10 km NNE Est. Marté, 25 Jul 1993, Turner 93–126 (TEX); same, Turner 93–138 (TEX); Sierra de la Paila, Ejido El Cedral, 25°57′N,101°33′W, 4 Oct 1989, Villarreal 5252 (TEX); Rancho Santa Teresa, S of Castaños, 19 Jun 1963 Wynd & Mueller 190 (A-with wide leaves; ARIZ, MO, US, with narrow leaves and referable to var. cinerascens); Cañón de Ybarra in Sierra del Pino, 22–23 Sep 1941, Stewart 1895 (LL); Sierra de la Cruces, Santa Elena Mines, 15 Oct 1940, Stewart 289 (LL). San Luis Potosí: San Luis Potosí, 1879, Schaffner 354 (US-1 of 3 specimens on sheet). Nuevo Leon: Sierra Madre Mts., Monterrey, 17 Jul 1933, Muller & Muller 117 (F, GH, TEX); Zacatecas: Rd between Colotlán and Platrado, 31 Aug 1897, Rose 3615 (US).

Type. UNITED STATES. Texas: Presidio Co., rocky hills about 12 miles S of Marfa, 18 Jun 1963, D. S. Correll & D. C. Wasshausen 27900 (holotype: LL!; isotypes: GH! MO! US!).

A Dyschoriste schiedeana var. schiedeana differt foliis crassioribus acutiorbusque et foliis ac floribus verticillatis; a D. schiedeana var. decumbenti ac var. prostatae differt habitu erecto et marginibus sepalorum ac carinae setis longioribus; a D. lineari differt absentia rhizomatum, foliis et bracteis vestimento uniformi intercostali (non limitato ad margines ac venas), et corollis brevioribus [(12.5-) 14–18(-20) mm longis vs. 18–26 mm longis].

Bushy, verticillate, erect-ascending, sometimes briefly decumbent herbs 0.8–3(-4)[-10] dm tall from an underground rootstock bearing fibrous roots; stems several, few-branched near the base with internodes 0.5–3(-6.2) cm long, closely pubescent, strigulose, strigose, or hirsutulous with antrorse curved, bent or spreading hairs 0.1–0.3 mm long to more strongly villous-hirsute to setose with dense, spreading, crisped hairs to 0.5–1.2 mm long mainly on the angles or with longer hairs on the angles and shorter hairs throughout. Leaves erect-ascending, oblanceolate, linear-spatulate to linear, moderately thick, (10-)12–25(-38) mm long, (2-)3–7(-14) mm wide, acute to sometimes rounded at apex, cuneate at base, the larger with petioles to 1–5(-8) mm long at the base, entire to commonly sinuate, sometimes closely undulate at the margins and thus sometimes appearing crenulate, uniformly pubescent to strigulose with antrorsely curled hairs 0.1–0.2(-0.3) mm long on both surfaces (these not confined to the veins and margins on the lower surface), the margins frequently, and the midrib less frequently, with longer curved or spreading hairs or setae 0.2–0.8 mm long, the blades flat or often conduplicate, often bluish-gray in color; bracts linear-spatulate to linear, (5-) 10–20 mm long, (0.7-) 1.5–3 mm wide, leaf like in texture and vestiture. Flowers with calyces 7–17 mm long, the tubes 2.2–5 mm long, the lobes 0.8–1 mm wide at the bases, 5–12 mm long, uniformly pubescent-strigulose to hirtellous throughout with hairs 0.1–0.2(-0.3) mm long, the hairs on the lower lobe and keel margins more setose-hirsute, 0.2–0.6(-1.2) mm long; corollas (12.5-)14–18(-20) mm long, the tubes cylindrical 4–7 mm long, the throat campanulate, to 5–6(-7.5) mm wide, the lobes oblong-obovate, 3.5–5.5 mm long and wide. Fruits 8–11 mm long.

Distribution (Fig. 2) and Habitat. Dyschoriste schiedeana var. cinerascens occurs in shallow calcareous-derived clay loams over limestone and sandy areas in grasslands, pine-juniper-oak woodlands, yucca-cactus scrublands, roadsides from trans-Pecos Texas south into eastern Chihuahua, northern Durango and across Coahuila, also San Luis Potosí from 1500–2200 m elevation; flowering from April through October dependent on the occurrence of the spring-summer rains.

Representative specimens examined: UNITED STATES. Texas: Jeff Davis Co.: 20 mi W of Alpine, 2 Sep 1977, Sanders 1090 (TEX); Pecos Co.: 11 mi E of Ft. Stockton, 27 Apr 1947, Warnock 5171 (LL); Presidio Co.: Alpine, Sul Ross campus, 7 Jun 1940, Warnock 21442 (TEX); Culberson Co.: Guadalupe Mts. Nat'l. Park, lower McKittrick Canyon, 9 Aug 1974, Northington 795 (TEX); 10 mi W of Kent, 30 Jul 1958, Correll & Wasshausen 27941 (LL); Reeves Co.: Jet. of US hwy 80 & 290, 13 Jul 1950, Gentry 690 (TEX). MEXICO. Chihuahua: 3 km ENE of Santo Tomás, E margin of Las Pampas Ranch, 27°21′N, 104°34′W, 28 Aug 1972, Chianget al 8965 (LL); 15 mi N of jet. hwys 45 & 49, 27 Jul 1975, Engard & Gentry 626 (LL). Coahuila: 7.5 mi N of Rancho El Jarín, 29°09′N, 102°12′W, 28 Jul 1973, Johnston et al 11843b (LL); Sierra del Pino, vie. La Noria, 20–26 Aug 1940, Johnston & Muller 693 (LL); 3 km N of Australia, Sierra de los Alamitos, 26°29′N, 102°19′W, 13 Jun 1972, Chiang7746 (LL). Durango: 11 mi E of La Zarca, rt. 30, 26 Jul 1958, Correll & Johnston 20227 (LL). San Luis Potosí: 9 mi E of San Luis Potosí, hwy. 86, 5 Jul 1973, Luckow 2688 (TEX).

This taxon can be distinguished by its bushy, rather compact, erect-ascending growth habit with leaves and flowers crowded at nodes, often separated by longer internodes, giving the plant a distinctive tiered or verticillate arrangement (Fig. 1H), and by its somewhat bluish-gray vegetative coloration. Plants vary considerably in flower size, habit size and particularly in vestiture.

In lightly vestiture plants, leaves and bracts have a sparse to moderately dense covering of antrorsely curved, tapering hairs 0.06–0.2 mm long on both surfaces without longer hairs on margins and veins. Stems have a similar uniform and close vestiture of antrorsely or sometimes retrorsely curved, tapering hairs 0.1–0.2 mm long with some longer uncurved spreading hairs at the nodes. Sepals will have some upcurved hairs 0.2–0.5(0.8) mm long along the margins and midvein. This very close vestiture pattern matches that found in many plants of Dyschoriste schiedeana var. schiedeana and var. decumbens. These plants may also have a yellow-green or olive-green coloration as in var. schiedeana or D. linearis rendering some of these plants difficult to classify.

A more commonly occurring pattern is with leaves and bracts having more dense intercostal spreading or curved-bent hairs 0.1–0.3 mm long, with some or many upcurved hairs 0.2–0.5(-0.8) mm in length along the lower margins and less frequently along the main veins beneath (Fig. 1I). Young stems may have only short hairs or a mixture of short and long spreading to upwardly curved hairs 0.2–0.8 mm long. These hairs may be uniformly arranged or the longer hairs may occur mostly on stem angles; basal internodes characteristically have a closer vestiture. Sepal lobes are vestitured as the leaves, but have longer hairs 0.2–0.5(-0.8) mm long along the margins and midvein (Fig. 1J).

Densely vestitured plants have leaves and bracts with dense antrorsely curved hairs to 0.3–0.5 mm long with longer hairs on the lower margins and main veins to 1 mm long. Stems are densely canescent and hirsute with both short and longer spreading, upcurved or crinkled hairs to 1.5 mm long and again the longer hairs may be dispersed or confined to the stem margins. Sepals are densely vestitured with longer setae along the margins and keels.

There is no geographical basis to the differences in vestiture encountered, nor are there three discrete morpho types, rather the above noted types are trends encountered over the range of the species. Plants with the sparse and close vestiture, as noted above, are similar in that character to Dyschoriste schiedeana var. decumbens, but var. cinerascens can be distinguished from var. decumbens by its erect-ascending habit. Plants of var. cinerascens with well developed decumbent lateral stems, however, may approach var. decumbens.

Dyschoriste schiedeana var. cinerascens shows strong mixing with var. schiedeana in its southernmost range where the distributions of the two taxa overlap. Separation of the two taxa is difficult as vestiture and structural patterns combine and often occur mixed in available collections. To separate the taxa I have relied on the habit differences with var. cinerascens having a distinctive verticillate, erect-ascending, non-rhizomatous growth habit, thicker stems, and thicker, bluish-gray leaves and bracts with curved hairs on the intercostal areas.

Dyschoriste schiedeana var. schiedeana, in contrast, tends to be rhizomatous and may form colonies of slender erectstemmed plants with thinner, more yellow-to olive-green leaves and bracts with hairs restricted to the upper surface and the margins and veins beneath. Plants considered to be influenced by var. cineras-censy tend to be more branched, have thicker, narrower leaves or leaves with curved hairs on both surfaces, and tend to have central erect-ascending stems and marginal decumbent stems; many plants included in var. schiedeana exhibit these characteristics.

As Dyschoriste schiedeana var. cinerascens approaches the southern portion of its range the plants tend to be of reduced stature, to have more decumbent spreading lateral stems, and a sparser leaf vestiture. Two collections from near San Luis Potosí [12 mi N of San Luis Potosí, McGregor et al 547 (LL-2); 9 mi E of San Luis Potosí, Luckow 2688 (TEX)] have the configuration, coloration, and leaf thickness of var. cinerascens, but have sparse understory leaf vestiture and tend to produce decumbent lateral stems as in var. prostrata, which also occurs in the region.

Ironically some specimens from montane habitats in the far northern range of Dyschoriste schiedeana var. cinerascens appear much like var. schiedeana. These specimens have erect stems, thin, rather long, olive-green leaves with sparse understory vestiture, and except for the generally larger corollas, they appear much like specimens from mountains south of Saltillo, Coahuila. These include the following: Texas: Culberson Co.: Guadalupe Mts., below McKittrick Canyon, Webster 4536 (GH). Jeff Davis Co.: Ft. Davis, Palmer 32082 (MO, TEX); Davis Mts., Palmer 30819 (MO); Davis Mts., Youngs.n. (GH). Brewster Co.: Greene Valley, Glass Mts., Warnock W590 (MO); Chisos Mts., Mueller 8167 (MO). The presence of these plants in the northern extreme of the range of var. cinerascens generally in higher woodlands and forests, indicates that environmental factors account for these differences.

Dyschoriste schiedeana var. cinerascens can be distinguished from Dyschoriste linearis by: (1) its lack of rhizomes-var. cinerascens develops directly from a underground fibrous-root bearing rootstock; (2) by its leaf and bract understory vestiture that is uniformly pubescent-strigose with antrorse curved or bent hairs on both surfaces not just confined to the veins and margins on the lower surface; (3) by its bluish gray, not yellowish- or olive-green coloration; and (4) by its generally smaller corollas (12.5-)14–18(-20) mm long (not 18–27 mm long). Intermediates between these two taxa are discussed under D. linearis.

Calophanes decumbens A. Gray, Syn. Fl. N. Am. ed. 1, 2⁽¹⁾: 325. 1875. Dyschoriste decumbens (A. Gray) Kuntze, Rev. Gen. PL 2:486.1891. Type. UNITED STATES. Arizona: Near Santa Cruz, stony soil in mountain valley, C. Wright 1462, [lectotype: (here designated) GH!; isolectotypes: GH! NY!] The number 1462 was assigned by Dr. Gray to all of Wright's collections of this taxon, thus Wright 1462 from “valley of the Rio Grande” at MO is not considered type material. Kobuski (1928) did not designate a type.

Procumbent, occasionally somewhat decumbent herbs 0.3–0.5 dm tall, 2–8 dm wide from a fibrous-root bearing underground rootstock; stems several from the base, radiating; internodes 0.5–4.5(-5.5) cm long, closely, uniformly puberulent, hirtellous to canescent with erect to antrorse, retrorse, curved, bent or crinkled white hairs 0.05–0.1 (-0.2) mm long. Leaves erect-ascending, oblanceolate, spatulate to linear-oblanceolate or linear (those of the lowermost stems sometimes obovate), (4-)10–30(-45) mm long, (2-)4–7(-15) mm wide, rounded, obtuse to acute, apiculate at apex, cuneate, the larger leaves with petioles 3–10 mm long at base, the margins entire to somewhat repand, green to grayish-green, usually uniformly puberulent to strigulose with mostly antrorsely curved or bent, often thickish hairs 0.05–0.1 (-0.2), long on both surfaces, those of the margins and veins on the lower surface often more dense. Flowers sometimes forming very dense aggregations with the bracts at the nodes; peduncles-pedicels 0.5–2(-9) mm long, generally more densely and closely vestitured than the stems; bracts leafy, spatulate to linear-spatulate, linear, (3-) 9–18 mm long, (1-) 1.5–4 mm wide; calyces (8-) 10–16.5 mm long, the tubes (3-)3.5–5.5 mm long, the lobes subulate, (6.5-)9–11 mm long, 0.7–1 mm broad at the base, closely and rather evenly pubescent throughout with hairs similar to those of the leaves, sometimes the hairs on the sepal margins somewhat longer but never over 0.3 mm long and never setose; corollas lavender, sometimes pinkish-lavender, with whitish or pale veins, sometimes with red-purple markings in the throat, 16–25.5 mm long, the tube 6–11 mm long, the throat 4–7 mm long, campanulate-funnelform, to 5–8 mm broad below the lobes; lobes oblong-obovate, (4-)5.5–8 mm long, 4–6.5 mm wide. Fruits 8.5–12(-13) mm long.

Distribution (Fig. 2) and Habitat. In open shallow limestone- and volcanic- derived soils in grasslands, flats, open oak and pine woodlands, foothill grasslands from Arizona, (Santa Cruz and adjacent Cochise, Pima counties) possibly New Mexico (Rio Grande Valley by Wright), south into eastern Sonora and the woodlands and grasslands of eastern slope of the Sierra Madre Occidental of Chihuahua and into Durango, disjunct in trans-Pecos Texas and in Baja California del Sur, mostly from 1300–2450 m, flowering from July through September.

Representative specimens examined: UNITED STATES. Texas: Brewster Co.: Blue Creek Trail, Chisos Mts., 9 Oct 1933, Cory 7344 (GH); Big Bend National Park, Chisos Mts., Pine Canyon, 17 Jun 1963, Correll & Wasshausen 27861 (LL). Jeff Davis Co.: E slope of Mount Lock, Davis Mts., 1 Sep 1935, Sperry T132 (US) (with closely crenulate leaf margins). Arizona: Pima Co., Greaterville, 16 Sep 1916, Shreve 4970 (ARIZ). Santa Cruz Co.: Patagonia Mts., 18 Aug 1928, Peebles, Harrison & Kearney 5608 (ARIZ). Cochise Co.: Ft. Huachuca Military Reservation, 20 Aug 1960, Goodding 232–60 (ARIZ), Picket Canyon, Chiricahua National Monument, 16 Aug 1934, Clark 8619 (ARIZ).

MEXICO. Baja California del Sur: Cape Region, Potrero de Almenta, head of S fork of Canon San Pedro, 23°19′N, 109°56′W, 10 May 1955, Moran 7392 (DS). Sonora: Region of Río Bavispe, El Tajo, Río Fronteras, 20 Aug 1941, White 4060 (ARIZ, GH); Quipur, 23 Jul 1970, Pennington 72 (TEX). Chihuahua: Vicinity Majalca Village, 11 May 1959, Correll & Johnston 21776 (LL); Rocky hills near Chihuahua, May 1885, Pringle 66 (GH, F, NY-2, US); 34 mi S of Parral, 9 Aug 1956, Waterfall 12522 (GH). Durango: Tepehuanes, 28 Jul 1944, Fisher 44297 (GH, MO, NY); 21 mi SE of Santiago Papasquiaro, 3 Aug 1970, Flyr 1525 (TEX); Llano Grande, 42 WSW of Cd. Durango, 10 Aug 1955, Maysilles 8493 (NY, TEX); 16 km SW of Durango along Hwy 20, 24 Jun 1964, Mick & Roe s.n. (US).

Dyschoriste schiedeana var. decumbens is characterized by its strictly decumbent growth habit and its close, very short, uniform vestiture on stems, leaves and calyces- the hairs along the calyx margins are typically the same length as those of the leaves, rarely to twice as long but never conspicuously long setose. Throughout its range it is quite variable in leaf size, vestiture and flower size. In Texas, Arizona, Chihuahua and northern Durango the plants flower during the late summer wet season; the specimens are usually quite large, have large leaves and a uniform vestiture of short, blunt curved hairs mostly 0.1 mm long on both leaf surfaces and stems. The short hairs continue onto the sepals; sepal margin and keel hairs are rarely to 0.2 mm long, never long setose. When leaves are large, vestiture may be rather sparse and sometimes conspicuously stronger on the leaf margins. In northern Sonora the local populations tend to. have large, nearly glabrous leaves except for small scattered hairs on the veins of the lower leaf surface and leaf margins as exemplified by White 3763, White 3705, Laferriere 1535. These are not nomenclaturely recognized as vestiture is often reduced in other fast-growing plants with large leaves and other specimens from the region have solitary flower, but are more strongly vestitured.

A single collection from Baja California del Sur (R. Moran 7392) reported by Daniel (1997) initially appeared to be distinct in having a very short stem and leaf vestiture only 0.03–0.05 mm long, with some specimens showing much longer hairs 0.3–0.7 mm long clustered on the margins and veins of younger leaves. While the longer tufted hairs were distinctive, they have been observed in occasional specimens elsewhere in the genus and are considered anomalous. The are not consistent in the specimens seen. The specimen in other ways appears to fit within Dyschoriste schiedeana var. decumbens.

In drier habitats from in eastern Chihuahua and Durango the plants have smaller leaves, often with a denser vestiture, and are overall more condensed. The presence of a disjunct population of Dyschoriste schiedeana var. decumbens in the Chisos Mountains of trans-Pecos Texas is surprising. While most of these collections have entire leaf margins, a few collections there have undulate-crenate margins as in Dyschoriste crenulata.

As the stems of Dyschoriste schiedeana var. decumbens are horizontal, the flowers are ascending to upright and relatively large. Total corolla lengths, based on 1 measurement per sheet, when available, from dried specimens, were 21–25.4 mm in Arizona, 16.5–19 mm for Texas, 15.5–24 mm for Chihuahua, and 14–24 mm for Durango.

Populations of Dyschoriste schiede-ana var. decumbens are well separated geographically from those of var. schiedeana. But they blend into var. schiedeana through the highly variable var. prostrata that ranges from central Durango to San Luis Potosí south into Guanajuato, Aguascalientes, Hidalgo, Puebla and Oaxaca. Dyschoriste schiedeana var. prostrata is also procumbent, but differs from var. decumbens in usually having shorter leaves (8-) 13–18(-25) mm long, a much coarser and less uniform vestiture with hairs often confined to the margins and veins on the lower leaf surface. The sepal margins are often more coarsely vestitured sometimes having some rather setose-like hairs to 0.4–0.6 mm long. Dyschoriste schiedeana var. prostrata also tends to have smaller corollas, particularly in its eastern range.

Dyschoriste schiedeana var. decumbens can be distinguished from var. cinerascens and D. linearis by its procumbent habit and its uniform, close, short, leaf and bract vestiture and the lack of longer ciliae on the sepal margins and keel. It is distinguished from the procumbent D. crenulata, as the latter has crenulate leaf margins, from D. greenmanii, as the latter is glabrous, from the procumbent D. poliodes by its conspicuously long hairs.

Type. MEXICO. San Luis Potosí: Region of San Luis Potosí, 1878, C. C. Parry & Ed. Palmer 699 (holotype: NY!, isotypes: F-2 sheets! GH! US!).

A Dyschoriste schiedeana var. decumbenti differt foliis minoribus vestimento minus uniformi et floribus generaliter minoribus.

Prostrate herbs with stems 1–2(-3) dm long; internodes 14–36 mm long, 0.7–1 mm in diameter, uniformly pubescent-hirtellous with erect to decurved, rather thickish hairs 0.05–1.5(-2) mm. long, the hairs rarely to 0.5 mm long and tapering. Leaves linear-oblanceolate to obovate, small and thickened or in some plants larger and thin, 6–20(-24) mm long, 1.8–4(-9) mm wide, acute to emarginate at the apices, long tapering and cuneate above a petiole 1–4 mm long at the base, sparsely to moderately pubescent throughout with thickish curved hairs 0.05–0.15 mm long, the hairs in the intercostal areas often falling leaving hairs mostly along the midvein on the upper surface and along the main veins beneath, occasional plants with tapering hairs to 0.4 mm long. Flowers sometimes forming dense nodal aggregations; peduncles-pedicels 0.5–2(-5) mm long, closely vestitured; bracts spatulate to linear oblanceolate, linear, leafy; calyces 8–11 mm long, tubes 2.5–4.5 mm long, lobes 6–7 mm long, pubescent throughout, the marginal hairs 1–2 mm long; corollas lavender, sometimes with lighter veins, sometimes purplish on lower lip, or pinkish throughout, 10–19 mm long, the tubes 4–9 mm long. Fruits 8–10 mm long.

Distribution (Fig. 2) and Habitat. In open shallow limestone- and volcanic-derived rocky soils in grasslands, cactus scrub, oak and pine woodlands, from central Durango, west to Zacatecas and southern San Luis Potosí to Aguascalientes, Guanajuato, Hidalgo, Puebla, and Oaxaca from 1700–2400 m elevation; flowering from May through September.

Representative specimens examined: MEXICO. Durango: Cd. Durango & vicinity, Apr-Nov 1896, Palmer 276 (GH, US); same data, Palmer 309 (F, MO, NY); same data, Palmer 930 (GH, MO, NY, US); 13 mi NE of Durango, rt. 31, 25 Jul 1958, Correll & Johnston 20160 (LL); Hwy 40, 8 km W of Durango, 31 Aug 1967, Oliver 654 (MO); Near La Purisima, 26 Aug 1939, Shreve 9178 (ARIZ, GH); Sierra Gamon above Peñón Blanco, 19–20 Sep 1948, Gentry 8359 (GH, US). Zacatecas: 20 mi NW of Fresnillo, Hwy 45,22 Aug 1975, Davidse 9998 (TEX); S slope of La Bufa, Cd. Zacatecas, 10 Aug 1948, Dressier 97 (MO, US); 6 mi S of Sierra Hermosa, 5 Sep 1938, Shreve 8603 (ARIZ, US). San Luis Potosí: Sierra de Alvarez, 22–25 rd mi ESE of San Luis Potosí, 20 May 1951, McVaugh 12251 (US); Sa. de San Miguelito, S of San Luis Potosí, 28 Jul 1934, Pennell 17723 (GH, US); 3 km N of Moctezuma, rd. to Venados, 2 Jul 1972, Chiang, Wendt & Johnston 8214h (LL). Aguascalientes: Mpio. San Jose de Garcia, 28.6 km N de Cd. Aguascalientes, 5 Jul 1983, Cowan 4026 (TEX). Guanajuato: Near San Miguel de Allende, Aug 1947, Kenoyer2460 (GH); Mpio. San Felipe, 25 km NNE de León, 8 Aug 1987, Galvan 2798 (TEX). Hidalgo: Mpio. Zempoala, Sierra de Pitos, 16 Sep 1973, Rzedowski 31220 (ENCB); Cerro Gordo, 7 km al W de Pachuca, 11 Jul 1967, Rzedowski 23920 (ENCB); 5 km al E de Tulancingo, 4 Jul 1979, Hernández 3302 (ENCB); 1 km N de Tolcayuca, 4 Sep 1971 y Jiménez 136 (ENCB). Puebla: Vicinity San Luis Tultitlanapa, Jul 1908, Purpus 3347 (F, MEXU); 4 km SSE of Cañada Morelos, 23°50′N 24°24′W, 16 Jul 1991, Mayfield et al 902 (TEX). Oaxaca: Dist. Coixtlahuaca, 2.5 km SSE de Concepción Buenavista, 23 Aug 1968, R. Cruz C. 2058 (ENCB).

With its generally smaller leaves, unevenly distributed leaf-bract vestiture Dyschoriste schiedeana var. prostrata appears to be a transitional taxon between the larger, more uniformly vestitured var. decumbens to the north and the equally small, often equally vestitured var. schiedeana to the east. Dyschoriste schiedeana var. schiedeana differs from var. prostrata only in habit, with var. prostrata having only procumbent stems while var. schiedeana has more erect or ascending central stems, but may have decumbent to procumbent marginal stems. Dyschoriste schiedeana var. schiedeana also has smaller flowers, but the corollas range from (9-) 13–19 mm and this overlaps with the corolla sizes characteristic of var. prostrata, which vary throughout its range. Corolla lengths of var. prostrata, as measured from dried specimens, are 14–19 mm for Zacatecas, 13.5–19 mm for San Luis Potosi, 16–18 mm for Guanajauto and Aguascalientes, and 12–17.5 mm for Hidalgo specimens.

Dyschoriste schiedeana var. prostrata represents a taxon intermediate between var. decumbens and var. schiedeana and it may have originated from introgression between the two taxa. Dyschoriste schiedeana var. prostrata is recognized as it nomenclaturally separates the broad zone of decumbent, unevenly vestitured plants from the uniform vestitured, often larger-leaved, larger-flowered plants of var. decumbens, throughout Chihuahua, Arizona, and trans-Pecos Texas and the more erect-ascending plants that characterize var. schiedeana from southeastern Coahuila to Hidalgo. But along each zone, many intermediate specimens exist. At one time I considered combining all the decumbent plants into var. decumbens, but it was apparent that the taxon was poly-phyletic with some plants representing true decumbens and others plants being either intermediate with or derived from var. schiedeana.

Rhizomatous herbs 1.5–4 dm tall forming colonies 2–8 dm in diameter; rhizomes 1–1.5 mm thick, dark brown, similar in size and color to the fibrous roots; stems briefly decumbent or erect-ascending with internodes l-3.5(-6) cm long, simple or few (-several) branched in the lower half, glabrous or sparsely to densely pubescent, strigose to villous-setose with retrorse to decurved, spreading, wavy or straight, tapering, mostly coarse, white, uniseriate hairs 0.1–1.2(-1.5) mm long, these or only the longer hairs restricted to the four angles of the stem. Leaves ascending-erect; lower leaves spatulate-obovate, large or commonly strongly reduced and soon deciduous; upper-mid leaves spatulate, linear-spatulate, oblong, to linear, 2–4.5(-6.5) cm long, (0.8-)2–10 (-13) mm wide, acute to rounded at the apices, narrowly cuneate, the larger leaves with winged petioles 1–5(-7) mm long at the base, entire to irregular sinuate-repand, yellow-green, the midveins, sometimes the lateral veins yellow and raised beneath, the midvein yellow and raised above, glabrous to mostly antrorsely pubescent or strigulose or more curved to spreading pilose-setose with white tapering hairs 0.1–0.8 (-1.2) mm long along a the margins and on the veins of the lower surface, sometimes also on the midrib above, the inter vein areas typically glabrous (except in var. sanpatriciensis), conspicuously lineolate (when dry). Flowers crowded in 1–3-flowered axillary dichasia; peduncles and pedicels 0.5–2 mm long; paired bracts leafy, linear-spatulate to linear 1–2(-3) cm long, 1–3.5 mm wide; calyces (11-) 15–20 (-23) mm long at anthesis, the tubes 4–6.5(-8) mm long, the lobes attenuate, subulate, to 0.7–1.7 mm wide at the base, glabrous to mostly pubescent and pilose-setose at least along the lower margins and on the raised midrib with antrorsely curved short hairs 0.1–0.3 mm long and longer spreading hairs (setae) 0.3–1 (-1.5) mm long; corollas lavender-blue, lavender-pink, often with purple and white markings on the lower lip and throat, ascending, 18–26 mm long, the tube cylindrical 5–8.5 mm long, the throat broadly campanulate, the lobes repand, oblong-obovate, 5–8 mm long, 4–6 mm wide, rounded; anthers 1.6–2 mm long, produced in the upper throat, basal spurs 0.2–0.4 mm long; lower filaments 3–5 mm long, the upper filaments 2–3.5 mm long; styles 17–20 mm long, extending beyond the anthers. Capsules 10–12.5 mm long, 2.2–2.5 mm broad; seeds 4, 2.8–3.2 mm long, 1.5–1.7 mm wide.

Dyschoriste linearis (Torr. & A. Gray) Kuntze, Rev. Gen. Pi. 2: 486. 1891; Dipteracanthus linearis Torr. & A. Gray, Bost. Jour. Nat. Hist. 5: 50 1845 (Pl. Lindh. 1:50); Calophanes linearis (Torr. & A. Gray) A.Gray. Syn. Fl. N. Am 2(1): 324. 1879. Type. UNITED STATES. Texas: Drummond 178 [lectotype: GH! (designated by Kobuski, 1928); isolectotype: TEX!]

Calophanes oblongifolius var. texensis Nees in DC. Prodr. 11: 108. 1847. Type. UNITED STATES. Texas: Drummond 178 [lectotype: (here designated) GH!; isolectotype: TEX!]

Leaves sparsely vestitured, the hairs confined to the leaf margins and midvein above and the main veins beneath, the intercostal areas glabrous or the leaves sometimes glabrous throughout; stems glabrous or with scattered setae along the angles; the sepals glabrous except for setae along the margins and keels of the lobes.

Distribution (Fig. 4) and Habitat. Mostly shallow calcareous clay-loams or gravelly loams mixed with or overlying limestone, in plains, prairies, hillsides, Tamaulipan scrub, roadsides, from southcentral Oklahoma, through central, western to southern Texas, south into Mexico (Múzquiz, Coahuila) where rare, 10–700 m; with flowers from April to June.

Representative specimens examined: UNITED STATES. Oklahoma: Cotton Co., 6 mi S of Randlette, 15 Jul 1949, Waterfall 9167 (NY). Texas: Dickens Co.: Dickens, 4 Jun 1961, Graham 11 (TEX). Garza Co.: E of Post, 19 May 1932, Reed 3591 (US). Borden Co.: 10 mi W of Gail, 10 May 1966, Correll 32809 (GH, LL). Nolan Co.: Sweetwater, 27 May 1918, Palmer 13758 (MO-2, US). Tom Green Co.: San Angelo, 18 May 1920, Pennell 10495 (NY). Baylor Co.: S of Semor, 26 May 1932, Clark 4689 (MO). Taylor Co.: Abilene, 22 May 1902, Tracy 8079 (F, GH, MO, NY, TEX, US). Crockett Co.: 25 mi S of Ozona, 21 Jun 1963, Correll & Wasshausen 27983 (LL). Val Verde Co.: 2 mi NW of Comstock, 15 Jun 1963, Correll & Johnston 27789 (GH, LL). Young Co.: Graham, 14 Jun 1941, Tharp s.n. (GH, TEX). Callahan Co.: 8 mi W of Clyde, 20 Jun 1946, Warnock 46339 (F, TEX). Eastland Co.: Ranger, 1935 Parks s.n. (GH). Brown Co.: 10 mi N of Brownwood, 5 Jun 1966, Ewing 7 (LL, TEX), Menard Co.: Menard, 11 May 1917, Palmer 11871 (MO, TEX). Blanco Co.: 8 mi E of Johnson City, 26 Jun 1946, Warnock 46485 (TEX). Kerr Co.: 4 mi SW of Kerrville, 28 Apr 1946, Cory 51766 (GH, NY, US). Kendall Co.: 2.5 mi SE of Comfort, 23 Jun 1963, Correll & Wasshausen 28058 (LL). Uvalde Co.: 3 mi N of Sabinal, 23 Jun 1963, Correll & Wasshausen 28026 (LL). Goliad Co.: Goliad, 1 Jun 1926, Williams 48 (F). Nueces Co.: Corpus Christi Bay, 9–12 Apr 1894, Heller 1529 (ARIZ, GH, F, MO, NY-2, US). Wise Co.: 5 mi E of Decatur, 1 Jun 1957, Correll 16508 (LL). Tarrant Co.: Ft. Worth, 9 May 1948, Cory 54414 (LL). Comal Co.: Comanche Springs, New Braunfels, May 1851, Lind-heimer 1063 (ARIZ, F, GH, MO, NY, TEX, US). Hamilton Co.: 8 mi N of Hamilton, 10 Jun 1955, Gould 6843 (TEX). Travis Co.: 11 mi W of Austin, 26 Jun 1946, Warnock 46462 (F). Burnet Co.: 2.7 mi E of Lampasas, 15 May 1955, Johnston & McCart 5370 (TEX-2). Milam Co.: 2 mi S of Rockdale, 16 May 1964, Bounds 259 (TEX). Jackson Co.: Ganado, 20 Mar 1916, Palmer 9218 (MO). San Patricio Co.: Welder Wildlife Refuge, 4 May 1958, Williges 67 (TEX). Matagorda Co.: Bay city, 6 May 1916, Palmer 9667 (MO, US).

MEXICO. Coahuila, Múzquiz, Spring 1935, Marsh 174 (F, TEX-2).

Dyschoriste linearis var. linearis is characterized by: (1) erect-ascending growth habitat (Fig. 3A); (2) the presence of slender underground rhizomes with the plants tending to form small colonies (Fig. 3A); (3) the larger ascending, broad-throated corollas (Fig. 3C-D); (4) the vestiture of leaves and bracts largely confined to the margins and veins of the lower surfaces and sometimes along the midvein above with the intercostal areas remaining glabrous (Fig. 3B).

This species shows variation in plant size (from 1 to 4 dm in overall height); in leaf size (ranging from linear-not exceeding 2 mm in width, to typically those with broader more spatulate leaf blades); and particularly in vestiture with the plants ranging from nearly glabrous to having well developed setae along the sepal and leaf margins and veins.

On one extreme are plants with glabrous stems, with leaves and bracts glabrous except for curved appressed marginal hairs 0.1–0.2 mm long along the margins and sometimes the major veins of the lower surface, and the sepal margins and keels have a mixture of similar small upwardly curved, tapering hairs and setae to 0.3–0.8 mm long. Other plants are more densely vestitured and have short decurved hairs (0.1–0.3 mm long) or short setae (0.3–1 mm long) on the stems (often in four decurrent rows), more setae on the leaf and bract margins and either setae or shorter decurved hairs on the veins of the lower surface and the basal midvein of the upper surface and the sepal margins and keels are typically setose with antrorsely curved hairs 0.3–1.2 mm long.

The variety can be distinguished from Dyschoriste schiedeana var. cinerascens as the latter lacks rhizomes and is not colonial, has smaller flowers 14–17(-22) mm long, and mostly narrower, thicker leaves with hairs continuing onto the intercostal areas on the lower surface, and generally more strongly vestiture in the inflorescence and a distribution west of the Pecos River and south into Mexico. However collections from Texas, [Terrell Co., 30 miles N of Sanderson, Warnock 14824 (LL, NY, TEX); 10 mi NW of Sanderson, Lundell & Lundell 14195 (LL); 18 mi S of Sheffield, Webster 221 (TEX); Pecos Co., 45 mi S of Fort Stockton, Correll 29883 (LL); Val Verde Co. 2 mi NW of Comstock, Correll & Wasshausen 27789 (LL)] all have the close, curved leaf-bract vestiture of var. cinerascens (or var. decumbens), and most of the specimens have rhizomes as in D. linearis implying that introgression between the taxa does occur in the region of overlap.

Other plants appearing much like Dyschoriste linearis var. linearis, but having a similar close vestiture of curved hairs and lacking setae except along the sepal margins also occur in south Texas; [Webb Co., 6 mi E of Laredo, Ibarra 61 (LL, TEX); Jim Wells Co., 17.4 mi S of Alice, Johnston 541212 (TEX); Jim Hogg Co., 30 mi S of Hebbronville, Tharp s.n. (TEX)]. These specimens are anomalous within D. linearisy but all have rhizomes and large flowers that otherwise conform to the characteristics of the species.

Dyschoriste linearis is considered a distinct species as it does not show strong introgression with the D. schiedeana, except as noted above with var. cinerascens. Its zone of introgression with var. cinerascens is relatively minor.

Type. UNITED STATES. Texas: San Patricio Co., along Nueces Bay, ca. 3.4 mi W of projected end of Hwy. 893, 7 May 1959, Traverse 1278 (holotype: TEX!; isotypes: F! LL! MO! US!)

A Dyschoriste lineari var. lineari differt vestimento denso, caulibus trichomata ac setas 0.5–1.2mm long parientibus, foliis in area intercostali paginae infera trichomata parientibus, et marginibus sepalorum ac carinae setis usque ad 1.5 mm longis.

Plants similar to those of var. linearis but more densely vestitured throughout The leaves with hairs present throughout the intercostal areas of both surfaces; the stems densely vestitured with hairs to 1.2 mm long; the hairs throughout the inflorescence dense, to 1.5 mm long.

Distribution (Fig. 4) and Habitat. Sandy, silty prairies, Tamaulipan scrub, coastal and southern border of Texas (Terrell and San Patricio counties), also northern Coahuila near Piedras Negras, 40–600 ft. Flowering in spring.

Representative specimens examined: UNITED STATES. Texas: Kleberg Co.: NE of Kingsville, 23 Apr 1949, Lundell 14933 (LL-3 sheets). Val Verde Co.: foot of Devils Lake, 20 mi NNW of Del Rio, 22 May 1949, McVaugh 10588 (US); Val Verde Co., without locality, May 1913, Orcutt 6029 (MO);

MEXICO. Coahuila: Piedras Negras, Howard s.n. (F, US).

Dyschoriste linearis var. sanpatriciensis is a minor varient comprised of strongly vestitured collections of D. linearis from southern Texas and adjacent Tamaulipas whose stems have dense hairs and setae 0.5–1.2 mm long, whose leaves and bracts have densely setose margins and veins with smaller decurved hairs on the intervein areas of the lower surface, and whose sepal margins and keels are densely setose with hairs to 1.5 mm long (Fig. 3G-H). These plants have a vestiture similar to that of D. poliodes var. poliodes of Nuevo León. In their rhizomes, erect-ascending stems, large leaves and large flowers they are otherwise typical of Dyschoriste linearis.

The type collection is distinguished by having the setae confined to the stem angles, rather than being universally distributed. This variety is known only from five scattered collections along the southern range of the species.

Dyschoriste crenulata Kobuski, Ann. Missouri Bot. Gard. 15:41. 1928. Type. MEXICO. Tamaulipas: San Fernando to Jiminey, 26–27 Feb 1902, E. W. Nelson 6604 (holotype: GH!; isotype: US!)

Perennial herbs with erect-ascending central stems and decumbent lateral stems, 0.5–3 dm tall, 2–8 dm wide from a woody rootstock with dark brown fibrous roots 1–1.5 mm in diameter; stems with internodes 1–3(-5) dm long, closely and uniformly canescent with mostly spreading to somewhat antrorse, slightly crinkled hairs 0.1–0.2(-0.3) mm long. Leaves erect-ascending, oblanceolate, spatulate or the lowermost more obovate, ovate, 1–3.5 (-4.5) cm long, 3–10(-15) mm wide, rounded to acute, sometimes apiculate at the apices, cuneate, the larger leaves with winged petioles 1–5(-9) mm long at the base, the margins repand-crenate to denticulate in the distal half, entire below, grayish-green to grayish, uniformly canescent on both sides with straight to slightly decurved, slender, tapering, white hairs 0.1 (-0.2) mm long. Flowers crowded in axillary 1–3(-5)-flowered dichasia; peduncles and pedicels 0.5–2(-4) mm long, vestitured as the stem; bracts leafy, spatulate to linear-oblanceolate, 8–20 mm long, 2–5 mm wide, with texture and vestiture of the leaves; calyx (11-) 14–16 mm long, the tube 4–6.5 mm long, the lobes subulate, 0.7–1.5 mm wide at the base, 6–10 mm long, uniformly pubescent-canescent throughout with spreading hairs 0.1–0.2 mm long (larger marginal and keel setae not present); corollas lavender with white-purple markings on the throat, (14.5-) 17–24 mm long, erect, the tube cylinder, (5.5-)7–11.5 mm long, the throat narrowly campanulate, the lobes oblong-obovate, 4–6 mm long, 3.5–5 mm wide, the longer filaments 4.5–5 mm long, the shorter filaments 2–3 mm long, anthers 1.2–1.4(-1.5) mm long with basal spurs 0.1–0.2 mm long. Fruits 10–11.5 mm long.

Distribution (Fig. 4) and Habitat. In sand, sandy-clay loams, clays, caliche areas in open Tamaulipan scrub and grasslands in southernmost Texas and adjacent Tamaulipas, Mexico; mostly 10–50 m elevation. Flowering from April to June.

Representative specimens examined: UNITED STATES. Texas: Starr Co.: 12.8 mi W of La Gloria, along rd 1017,31 May 1974, Fleetwood 11006 (TEX); 17 mi NE of Rio Grande City, 3 Apr 1941, Lundell 9915 (LL). Hidalgo Co.: Samfordyce, 1 Sep 1925, Runyon 897 (TEX, US); 12 mi N of Mission, 4 Apr 1941, Lundell 9957 (ARIZ, LL). Willacy Co.: 3 mi N of headquarters of Sauz Ranch, 29 Jul 1953, Johnston 53266.17. Cameron Co.: 1 mi S of Sebastion, 21 Apr 1959, Correll & Rollins 20995 (GH, LL, MO, NY, US); Brownsville, 1942, Schiller 688 (US-3).

MEXICO. Tamaulipas: 20 mi W of Reynosa 28 Feb 1944, Barkley & Painter 14393 (GH, NY, MO, TEX); 48 mi from Reynosa on San Fernando Road, 27 mi from Matamoros-San Fernando Hwy, 19 Oct 1959, Johnston & Graham 4382 (TEX); Sierra de San Carlos, vicinity San Miguel, 27 Jul 1930, Bartlett 10646 (F). Coahuila: 30 mi SW of Monterrey, 1 Dec 1945, Warnock & Barkley 14806M (F, TEX).

This species is characterized by its spreading habit with erect-ascending central stems and decumbent-procumbent lateral stems, by closely crenulate leaf margins, by having a uniform and relatively dense vestiture of short hairs mostly to 0.15–0.2 mm long on stems, leaves, bracts, and sepals, of a type similar to that found in Dyschoriste schiedeana var. decumbens. The larger setae characteristic of D. linearis and D. schiedeana var. cinerascens are not present in this taxon. The taxon can be distinguished from D. schiedeana var. decumbens by its more erect habit, its distinctly crenulate leaf margins, and its distribution in south Texas and adjacent Tamaulipas. Dyschoriste crenulata is recognized as a species as it appears not to intergrade with other taxa of the complex.

Grayish, strongly vestitured, perennial, rhizomatous herbs producing decumbent-procumbent spreading stems 1.5–5 dm long, occasionally with erect-ascending stems to 2 dm high from the plants center or along extended rhizomes; stems internodes 1.5–4(-6.2) cm long, 0.5–1.1 m in diameter, strongly hirsute-pilose with spreading, straight or variously wavy, white hairs (0.2-)0.5–1.2 mm long or nearly glabrous with decurved pubescence to 0.1 mm long. Leaves oblong-ovate to oblong-elliptical to elliptical-lanceolate, to linear lanceolate, more ovate when smaller, (11-) 15–25(-40) mm long, (3-)4–14 mm wide, rounded, obtuse to acute at the apices, broadly cuneate at the base and tapering to a channeled petiole 1–4 mm long at the base, entire or commonly irregularly erose, moderately thickened, the blades slightly bicolored, moderately to densely pilose-hirsute on both surfaces with long, slender, spreading or terminally wavy hairs 0.3–0.7(-1.2) mm long or glabrous except where pubescent along the lower margins. Flowers 1–5(-9) per leaf axil in leafy-bracted dichasia; peduncles to 2 mm long, bracts leafy, narrowly lanceolate, 5–15 mm long, (1.2-)2–4 mm wide, vestitured as the leaves; calyces 9.5–18 mm long, the tubes 3–5 mm long, the lobes lanceolate, 6–10 mm long, strongly pilose-setose to puberulent on the tube and lobes, the hairs (0.1-)0.5-l mm long, typically curved upward along the sepal margins; corollas purple-lavender, violet, 14–28 mm long, tube 6–10 mm long, throat ampliate, 4.2–9.5 mm long, lobes oblong-obovate, 5–9 mm long, 3.5–6.5 mm wide; anthers 9.5–2.1 mm long, spurs 0.15 mm long; short free filament 2–4 mm long, long free filament 3–5 mm long; style 11–14 mm long, slightly puberulent. Fruits 9–11 mm long.

Dyschoriste poliodes is distinguished by its mostly decumbent growth habit, its usual dense, long pilose-hirsute vestiture on stems and leaves, by its narrowly ovate to linear-lanceolate leaves, and its few flowers per node. The taxon, however, exhibits considerable variation, with some plants being subglabrous and having long corollas and others having narrower leaves and more flowers per node. To accommodate this variation, three varieties are recognized, separable by the following key.

Dyschoriste poliodes Leonard & Gentry, Brittonia 6: 326.1948. Type. MEXICO. Nuevo León: 3 mi W of Montemorelos, 14 Aug 1942, H. S. Gentry 6721 (holotype: US!; isotype: Gentry Herbarium now at DES).

Decumbent, grayish, densely pilose-hirsute perennial herbs, occasionally rhizomatous; stems spreading, sometimes forming erect stems 1–2 dm tall near the root or along the rhizomes; young stems hirsute-pilose with straight or wavy, white hairs 0.2–1.2 mm long. Leaves ovate, oblong-ovate to lanceolate, (11-) 14–25(-40) mm long, 3–7(-12) mm wide, moderately to densely pilose-hirsute throughout with hairs 0.3–0.7 mm long. Flowers l(-2) per leaf axil; bracts narrowly lanceolate, 7–15 mm long, 2–4 mm wide, leaf-like in vestiture; calyces (9.5-) 13–14(-18) mm long, the tubes 4–5(-6.3) mm long, the lobes 6–11 mm long with marginal hairs 0.3–0.5 mm long; corollas 14–22 mm long, the basal tube 6–9.2 mm long, the ampliate throat 4–6 mm long, the lobes oblong-obovate, 4.5–5.5 mm long, 3.5–4.2 mm wide.

Distribution (Fig. 4) and Habitat. Known from in arid oak scrub to forested hills, roadsides in limestone areas, from northern to central Nuevo León from 330 to 1000 m elevation.

Representative specimens examined: MEXICO: Nuevo León: Mts. E of State hwy 34,1.4 km N of Bustamente, then 16.3 km E of hwy, 15 Mar 1983, Cowan & Nixon 3820 (TEX); Mt. Chipinque Road, Monterrey, 12 May 1960, Smith M210 (TEX); Sierra Madre Mts., Monterrey, 7 Jul 1933, Mueller 115 (GH); same area, 12 Jul 1933, Mueller 113 (F, GH); same area, 14 Jul 1933, Mueller 119 (GH); Hacienda Vista Hermosa, 35 mi S of Monterrey, 27 Jun 1939, White 1579 (GH); above Horsetail Falls, near Hacienda de Vista Hermosa, 20 Jun 1940, Leavenworth 131 (F, GH, MO); 5 mi N of Villa Santiago, 14 Jul 1946, Rowell & Barkley 16m367c (TEX); below Ebanito, Dist. Linares, 12 May 1980, Hinton 17786 (TEX); Rio Ramos, 20 km NW of Montemorelos, 5 Jun 1942, Weaver 564 (GH, TEX); 16 mi W of Linares, road to Galeana, 19 Jul 1958, Correll & Johnston 19778A (LL); Horsetail Falls, ca. 20 mi SSE of Monterrey, 22 May 1974, McPherson 880 (ENCB).

Dyschoriste poliodes var. poliodes is characterized by its decumbent growth habit, although the horizontal stems or rhizomes may produce series of erect stems forming rather bushy colonies, its distinctive long pilose-hirsute vestiture on stems, leaves and calyces, its oblong-ovate leaf blades, the basal blades more ovate the upper ones more lanceolate, its mostly solitary flowers in the leaf axils, and its moderately long corollas 14–22 mm long. Most of the specimens show strong growth, and some specimens have very large leaves.

Type. MEXICO. Nuevo Leon: Sembradas en medio de la piedras del monte en la vecinidad del Cerro del Obispado, cerca de Monterrey, 29 Jun 1944, C. Fernandez C. & F. A. Barkley 14512B (holotype: MO!; isotypes: F! MEXU! NY! TEX!)

A Dyschoriste poliode var. poliode differt foliis oblongis-oblanceolatis (non ovatus) floribus (1-)2–5 [non 1 (-2)] per axil, calycibus viejos persis-tente in callibusque.

Mostly decumbent to erect-ascending perennial herbs, the plants often bearing erect stems near the roots; stems long pilose-hirsute with hairs (0.2-)0.4–1.2 mm long. Leaves oblong-oblanceolate, oblong-lanceolate to oblong, 1.3–2.5(-3) cm long, 1.5–5 mm wide, acute at apex, abruptly cuneate above a channeled petiole 1–5 mm long at base, entire, coarsely pilose-hirsute with white, tapered wavy- tipped hairs 0.5–0.7 mm long throughout or in some specimens the hairs more sparse and confined to the leaf margins and lower surface veins, the blades commonly conduplicate and sometimes arching abaxially. Flowers in axillary dichasia of 1–5(-9); bracts oblanceolate, linear-oblanceolate, 5–10(-20) mm long, (0.5-) 1–2.5 mm wide, leaf like in texture, color and vestiture; calyces 10–13 (-17) mm long, the tubes 3–4.5(-5) mm long, lobes subulate, 5.5–7.5(-9) mm long, strongly keeled, with tapered, wavy hairs 0.2–0.7 mm long at the margins and keel, the older calyces turning gray and tending to persist at the nodes; corollas 13–16.5 mm long, basal tube 4–6 mm long, the ampliate throat 4–5.5 mm long, the lobes 3.5–5(-7) mm long, 2–5.5 mm wide.

Distribution (Fig. 2) and Habitat. Dyschoriste poliodes var. obispoensis accommodates the distinctive specimens from the Obispado, a limestone hill within the city of Monterrey topped by a ancient cathedral.

Representative specimens examined: MEXICO. Nuevo León: Limestone hills cerca Monterrey, below the Obispado, 25 Feb 1946, Johnson & Barkley 15045M (F, TEX); Loma del Obispado, Monterrey, 31 Jun 1907, Safford 1214b (US); Obispado, Arsene 187 (MO); Obispado, Arsene 6411 (US).

Specimens of Dyschoriste poliodes var. obispoensis have a long pilose-hirsute vestiture as found in var. poliodes, but differ from var. poliodes in having narrower, more oblong-oblanceolate leaves as in var. greenmanii (leaves of D. greenmanii, however, are nearly glabrous). Flowers in var. obispoensis number (1-)2–5 flowers per leaf axil, not l(-2) per leaf axil in var. poliodes and var. greenmanii, and the older, dried, gray calyces tend to persist at the nodes giving the plants a distinctive appearance. As in var. poliodes, the plants tend to form erect lateral stems along the horizontal stems or rhizomes. Overall, specimens of Dyschoriste from the Monterrey region show considerable diversity, perhaps reflecting long history of disturbance as well as geographically diversity.

Type. MEXICO. Nuevo León: Mesas N of Monterrey, 13 Jun 1935, Ora M. Clark 6778 (holotype: MO!)

A Dyschoriste poliode var. poliode differt foliis calycibus caulibusque glabris vel sparsim puberulis trichomatibus tenuibus usque ad 0.1 mm longis (non grosse pilosi-hirsutis trichomatibus 0.4–1.2 mm longis) et corollis 22–28 mm longis (non 15–22 mm longis).

Decumbent perennial herbs; stems sparsely puberulent with descending curved hairs to 0.1 mm long in the sulci or glabrous. Leaves obovate, elliptical to broadly elliptical, 11–22 mm long, 3.7–10.2 mm wide, glabrous throughout or very sparsely puberulent with ascending curved hairs to 0.1 mm long along the lower margins. Flowers 1(-2) per node; bracts elliptical to oblanceolate, 6–12 mm long, 1.5–3.5 mm wide; calyces 11.5–16.2 mm long, the tube 3.5–6 mm long, the lobes broad, to 1 mm wide at the base and tapering to the apex, 7.5–10.5 mm long, with a prominently thickened midvein, appearing glabrous but with sparse, slender, antrorsely curved hairs 0.1 mm long along the margins and on the inner lobe surfaces; corollas 22–28 mm long, the tubes 9–10 mm long, the ampliate throats 7.5–9.5 mm long, the lobes 6–9 mm long, 5–6.5 mm wide.

Distribution (Fig. 4) and Habitat. Dyschoriste poliodes var. glabra is known from three collections near Monterrey, in openings and roadsides in thorn scrub at 500–1000 m elevation.

Representative specimens examined: MEXICO. Nuevo León: 5 mi SE of Monterrey on Mex 85 and 2 mi W of Valle Alto, 14 Jun 1971, Parker 418 (LL); Monterrey, 5 Jul 1938, Cottam 10585 (ARIZ).

Dyschoriste poliodes var. glabra is named to accommodate a small series of specimens with more or less glabrous, elliptical-obovate leaves, slender, decumbent stems, mostly solitary flowers at the nodes with distinctive, nearly glabrous, calyces with broad lobes, and large corollas 22–28 mm long. In the decumbent habit, ovate leaves, solitary flowers this variety resembles D. poliodes var. poliodes, but differs conspicuously in its dense pilose-hirsute vestiture and smaller corollas. In its lack of strong vestiture, it approaches D. greenmanii, but the latter has linear to linear-oblong leaves that are hairy along the margins and veins beneath, and corollas 12.5–16 mm long. The three known collections, all from the vicinity of Monterrey, are very similar in several characteristics giving credence that this represents a variety and not a sporadic recombinant forma.

Dyschoriste greenmanii Kobuski, Ann. Missouri Bot. Gard. 15: 33. 1928. Type. MEXICO. Tamaulipas:, vicinity of Victoria, ca. 320 m, 1 May-13 Jun 1907, E. J. Palmer 492 (holotype: US!, isotypes: F! GH!)

Procumbent, sprawling perennial herbs; stems 2–6 dm long; internodes (8-)15–35(-45) mm long, 0.5–1.1 mm in diameter, quadrangular, convex-sulcate, sparsely puberulent with decurved hairs to 0.1 mm long in the sulci, sometimes glabrous, except were pilose at the nodes, green, often becoming purplish with age. Leaves linear, linear-oblanceolate, oblong when larger, 15–25 (-45) mm long, 1.1–4(-6) mm wide, acute to obtuse at the apices, cuneate above a short petiole at base, at margins entire to erose, thickish, flat to conduplicate, usually closely strigose with antrorse hairs 0.1–0.3 mm long along the margins and main veins beneath, otherwise glabrous, the blades yellow-green to olive green in specimens. Flowers solitary in leaf axils; peduncles 1–1.5 (-4) mm long; pedicels 0–1 mm long; bracts linear-oblanceolate 8–15 mm long, 0.7–1.5 mm wide; calyces 10–18 mm long, tube 3.5–6 mm long, glabrous, the lobes subulate, green, 6–10(-13.5) mm long, the midrib prominent, the margins setose with hairs 0.2–0.3(-0.4) mm long; corollas lavender-purple, 12.5–16 mm long, the tube 4.5–7 mm long, the throat moderately ampliate, 4–6 mm long, the lobes oblong-obovate, emarginate, the upper lobes 3.3–4 mm long, 2.4–3.5 mm wide, the medial lower lobe 3.5–6 mm long, 2.3–5.2 mm long; anthers glabrous 1.1–1.6 mm long, basal spur 0.12 mm long; longer free filament 2.7–4 mm long; shorter free filament 2–3 mm long; style 10–14 mm long, exserted beyond the anthers. Fruits 8.5–10 mm long.

Distribution (Fig. 4) and Habitat. Limestone, caliche slopes and flats in Tamaulipan scrub, oak scrub, rocky grasslands, in Nuevo León and Tamaulipas, 150–1100 m elevation, with flowers from May to December.

Representative specimens examined: MEXICO. Coahuila: 23 mi SW of Monterrey, 1 Dec 1945, Warnock & Barkley 14856M (F-2, TEX). Nuevo León: above Mamulique Pass, 36 km. S of Sabinas Hidalgo, 26°11′N, 100°06′W, 7 Apr 1990, Bridges & Woodruff (TEX); 57 km N of Monterrey towards Nuevo Laredo, 23 Apr 1939, Frye & Frye 2460 (GH, MO-2, NY, US); Microwave tower at pass where Hwy 53 passes over Sierra el Rincon del Arco between Monterrey and Monclova, 26°15′N, 100°40′W, 18 Oct 1993, Patterson etal 6422 (TEX). Tamaulipas: 6 mi N of Santander Jiménez, 9 Dec 1959, Johnston 4899 (TEX); 8.1 mi E of Soto de Marina to La Pesca, 23°51′N, 98°00′W, 6 Oct 1993, Patterson & Mayfield 7274 (TEX); 3–5 km S of Huisachal, 27 Jun 1949, Stanford et al 2141 (NY, US).

Dyschoriste greenmanii is characterized by its procumbent growth habit, its slender, subglabrous, greenish, often long stems, its narrow, nearly glabrous leaves with usually antrorsely appressed hairs along the lower margins and solitary flowers at the nodes. In these characteristics is remains a relatively easily recognized taxon. However, variation occurs in vestiture with most specimens being glabrous or with very small hairs while other specimens are more coarsely hairy along the leaf and calyx-lobe margins and stem sulci. In one gathering of four specimens [Tamaulipas: 8 mi E of Dulces Nombres, 25 Jun 1948, Meyers & Rogers 2673 (GH, MO, NY, US)] three specimens have nearly glabrous leaves, solitary flowers, and fit well into D. greenmanii, while the fourth (MO) has leaves pubescent throughout and multiple flowers at the nodes, the latter possibly having introgressed with D. schiedeana var. schiedeana.