The genus Stipa L. comprises over 150 species, all native to the Old World, where they grow in warm temperate regions throughout Europe, Asia, and North Africa. It is one of the largest genera in the family Poaceae in Middle Asia, where one of its diversity hotspots is located. However, identification of Middle Asian Stipa species is difficult because of the lack of new, comprehensive taxonomic studies including all of the species recorded in the region. We present a critical review of the Mid-Asian representatives of Stipa, together with an identification key and taxonomic listing. We relied on both published and unpublished information for the taxa involved, many of which are poorly known. For each taxon, we present a taxonomic and nomenclatural overview, habitat preferences, distribution, altitudinal range, and additional notes as deemed appropriate. We describe four new nothospecies: S. ×balkanabatica M. Nobis & P. D. Gudkova, S. ×dzungarica M. Nobis, S. ×pseudomacroglossa M. Nobis, S. ×subdrobovii M. Nobis & A. Nowak, one subspecies S. caucasica Schmalh. subsp. nikolai M. Nobis, A. Nobis & A. Nowak, and eight varieties: S. araxensis Grossh. var. mikojanovica M. Nobis, S. caucasica var. fanica M. Nobis, P. D. Gudkova & A. Nowak, S. drobovii (Tzvelev) Czerep. var. jarmica M. Nobis, S. drobovii var. persicorum M. Nobis, S. glareosa P. A. Smirn. var. nemegetica M. Nobis, S. kirghisorum P. A. Smirn. var. balkhashensis M. Nobis & P. D. Gudkova, S. richteriana Kar. & Kir. var. hirtifolia M. Nobis & A. Nowak, and S. ×subdrobovii var. pubescens M. Nobis & A. Nowak. Additionally, 12 new combinations, Achnatherum haussknechtii (Boiss.) M. Nobis, A. mandavillei (Freitag) M. Nobis, A. parviflorum (Desf.) M. Nobis, Neotrinia chitralensis (Bor) M. Nobis, S. badachschanica Roshev. var. pamirica (Roshev.) M. Nobis, S. borysthenica Klokov ex Prokudin var. anomala (P. A. Smirn.) M. Nobis, S. holosericea Trin. var. transcaucasica (Grossh.) M. Nobis, S. kirghisorum P. A. Smirn. var. ikonnikovii (Tzvelev) M. Nobis, S. macroglossa P. A. Smirn. var. kazachstanica (Kotuchov) M. Nobis, S. macroglossa var. kungeica (Golosk.) M. Nobis, S. richteriana var. jagnobica (Ovcz. & Czukav.) M. Nobis & A. Nowak, and S. zalesskii Wilensky var. turcomanica (P. A. Smirn.) M. Nobis are proposed, and the lectotypes for 14 taxa (S. arabica Trin. & Rupr., S. bungeana Trin. ex Bunge, S. caspia K. Koch, S. ×consanguinea Trin. & Rupr., S. effusa Mez, S. ×heptapotamica Golosk., S. jacquemontii Jaub. & Spach., S. kungeica Golosk., S. margelanica P. A. Smirn., S. richteriana, S. rubentiformis P. A. Smirn., S. sareptana A. K. Becker, S. tibetica Mez, and Timouria saposhnikovii Roshev.) are designated. In Middle Asia the genus Stipa comprises 98 taxa, including 72 species, four subspecies, and 22 varieties. Of the 72 species of feather grasses, 23 are of hybrid origin (nothospecies). In Middle Asia, feather grasses can be found at elevations from (0 to)300 to 4500(to 5000) m, but most are montane species. The greatest species richness is observed at altitudes between 1000 and 2500 m. Nineteen species grow above 3000 m, but only nine above 4000 m. The number of taxa (species and subspecies) growing in each country also varies considerably, with the highest noted in Kazakhstan (42), Tajikistan (40), and Kyrgyzstan (35). Of the 76 taxa of Stipa (species and subspecies) recorded in Middle Asia, 41 are confined to the region, with some being known only from a single country or mountain range. Distribution maps of selected species are provided.

A comprehensive systematic monograph is presented for the genus Operculina Silva Manso (Convolvulaceae). Formerly included in tribe Merremieae D. F. Austin, now incertae sedis, recent systematic studies have clarified the phylogenetic relationships for Operculina and unequivocally demonstrated that it is monophyletic as currently circumscribed and that the unique operculate capsule is a synapomorphy for the genus. Other morphological characters useful for recognizing the genus are: large sepals forming a “pear-shaped” calyx that is broad at the base and tapers upward; calyx that is accrescent and persistent, often cupping the mature fruit; strongly spirally coiled anthers after dehiscence; and axial parts of the plant body (stems, petioles, peduncles, pedicels) that are often prominently winged. The current monograph accepts 13 species, including one variety and one purported hybrid; these taxa are distributed throughout the tropics globally. The hybrid is proposed to accommodate the extraordinary phenotypic variability and intermediacy among South Pacific populations of Operculina. The monograph provides detailed descriptions for all taxa, as well as an identification key, distribution maps, and summaries of ecology, phenology, vernacular names, and uses, with comments on synonymy, typification, variability, biology, and conservation, where appropriate. All names published or combined in Operculina (about 60 epithets) are accounted for as accepted names, synonyms, misapplied names, or uncertain names, or are excluded from the genus. New reductions to synonymy are proposed as follows: O. brownii Ooststr. becomes a synonym of O. codonantha (Benth.) Hallier f.; O. tansaensis Santapau & V. Patel becomes a synonym of O. ventricosa (Bertero) Peter. Lectotypes, neotypes, and epitypes are designated where necessary to stabilize names in current use. An index to numbered collections examined is provided to aid in specimen identification and herbarium curation.