Miller, J.S. & M. Gottschling (2017). Generic transfers in Malagasy Boraginales. Candollea 72 : 329–332. In English, English and French abstracts.
Recent molecular data have demonstrated convincingly that the Old World genus Hilsenbergia Tausch ex Meisn. (Ehretiaceae) is nested within the New World genus Bourreria P. Browne. Thus, 13 new combinations are required to accommodate the endemic Malagasy species in Bourreria. Additional studies have demonstrated that Heliotropium sect. Orthostachys R. Br. (Heliotropiaceae) is not closely related to the rest of the genus and should be segregated as Euploca Nutt. Three species that occur in Madagascar fall into this group, including one endemic that requires a new combination.
Introduction
Thulin (1987) recognized five species from eastern Africa and the Mascarenes as differing from other African species of Ehretia P. Browne (Ehretiaceae) in having valvate calyx lobes and pyrenes (i.e., fruit parts) with overlapping lamellae, features shared with the circum-Caribbean genus Bourreria P. Browne. He described one of the five species as new to science and created new nomenclatural combinations for the other four in Bourreria. Miller (2003) described an additional 13 species of Ehretiaceae, all endemic to Madagascar, and resurrected the genus Hilsenbergia Tausch. ex Meisen. to accommodate them, based on their much smaller urceolate corollas (New World Bourreria species have rotate to salveriform corollas), their distinct geographic distribution, and ITS sequence data for a very limited subset of the species (Gottschling & Hilger, 2001).
More recent studies of sequence data from both nuclear and chloroplast genes and based on a much larger sample of species (Gottschling et al., 2014) indicate that Hilsenbergia species are nested within Bourreria rather than being its sister group. This confirms the assumption of close relationship proposed by Thulin (1987) but is in conflict with their segregation from the New World species. Bourreria, also in this broader and morphologically more heterogeneous circumscription, remains distinct — the combination of the valvate calyx aestivation, the extensive disc in the flower and an additional sterile chamber in each pyrene is not found in any other member of the Ehretiaceae (Gottschling, 2004). In preparing a treatment of Boraginales (in the sense of Luebert et al., 2016) for the Flore de Madagascar et des Comores, it is necessary to make new nomenclatural combinations for the endemic species.
Recent studies of members of the Heliotropiaceae (Hilger & Diane, 2003) show that one of the major clades of Heliotropium is not related to the core group of species and is sister group to two other genera of the family. The authors conclude that it should be recognized as a distinct genus, Euploca. Three species found in Madagascar fall within the clade, including one endemic species which requires a new nomenclatural combination.
Transfers to Bourreria
Bourreria angustifolia (J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia angustifolia J.S. Mill. in Adansonia ser 3, 25 : 158. 2003.
Typus : Madagascar. Prov. Toliara : près d'Andrenialamahitsy, au N du Lac Ihotry, [21°50′S 43°40′E], 27.V.1965, Service Forestier 24122 (holo- : P [P00417673]!; iso- : G, K, MO-5582595!, P [P00417674]!, TEF [TEF000088]!).
Bourreria apetala (J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia apetala J.S. Mill. in Adansonia ser 3, 25 : 160. 2003.
Typus : Madagascar. Prov. Mahajanga : Ambongo, au S d'Antsakomanera, baie de Marambitsy, 16°30′S 44°40′E, 20.XI.1965, Service Forestier 24232 (holo- : P [P00417675]!; iso- : G, GH, K, MO-5582603!, P [P00298699]!, TEF [TEF000089]!, WAG [WAG0248972] image seen).
Bourreria bosseri (J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia bosseri J.S. Mill. in Adansonia ser 3, 25 : 162. 2003.
Typus : Madagascar. Prov. Toliara : 95 km W of Fort Dauphin, on RN 13, at Andalitany, 200 m, 25°08′S 46°12′E, 29.III.1991, Miller & Randrianasolo 6182 (holo- : MO-3801522!; iso- : G [G00341684] image seen, K, MO-3801523!, P, TAN [TAN000457]!, WAG [WAG0304635] image seen).
Bourreria capuronii ( J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia capuronii J.S. Mill. in Adansonia ser 3, 25 : 164. 2003.
Typus : Madagascar. Prov. Toliara : forêt d'Analalava, c. 14 km N of RN 7, W of Isalo NP, E of the Malio River, 670 m, 22°35′26″S 45°08′16″E, 27.I.2003, Miller et al. 10737 (holo- : MO-04876342!; iso- : CAS [CAS1164451] image seen, G [G00386540] image seen, K [001081859] image seen, P, TAN).
Bourreria comorensis ( J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia comorensis J.S. Mill. in Adansonia 25 : 167. 2003.
Typus : Comores. Mayotte : Hachiroungour, 450 m, 16.IV.1996, Pascal 504 (holo- : P [P00144492]!; iso- : K).
Bourreria croatii (J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia croatii J.S. Mill. in Adansonia ser 3, 25 : 168. 2003.
Typus : Madagascar. Prov. Toliara : Tsivonoakely, 20–30 km N of Tuléar on the road to Morombe, 5–10 m, 23°12′S 43°37′E, 11.XI.1989, Miller & Keating 4514 (holo- : MO-3765989]!; iso- : G [G00341685] image seen, P, TAN).
Bourreria darcyana (J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia darcyana J.S. Mill. in Adansonia ser 3, 25 : 170. 2003.
Typus : Madagascar. Prov. Toliara : e n v. d'Ampandrandava, entre Bekily et Tsivory, 1000–1100 m, [24°05′S 45°42′E], s.d., Seyrig 5404 (holo- : P [P00298612]!; iso- : MO-5582605!).
Bourreria labatii (J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia labatii J.S. Mill. in Adansonia ser 3, 25 : 173. 2003.
Typus : Madagascar. Prov. Antsiranana : collines et plateau calcaires de l'Ankarana, 300 m, [12°54′S 49°08′E], XII.1937-I.1938, Humbert 18924 (holo- : P [P00853280]; iso- : G [G00341681], K, MO-5613311!, P [P00417677]!, TEF, WAG [WAG0248971] image seen).
Bourreria leslieae (J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia leslieae J.S. Mill. in Adansonia ser. 3, 25 : 174. 2003.
Typus : Madagascar. Prov. Toliara : 14 km SE of Tuléar on the road to Sakaraha, 100 m, 23°21′S 43°42′E, 26.XII.1988, Miller & Miller 3787 (holo- : MO-3667627!; iso- : K, MO-3667628!, P [P00417678]!; TAN [TAN000458] image seen, WAG [WAG0247494] image seen).
Bourreria lowryana ( J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia lowryana J.S. Mill. in Adansonia ser 3, 25 : 177. 2003.
Typus : Madagascar. Prov. Fianarantsoa : dans la vallée de la Manarahaka, à l'E d'Ihosy, [22°19′S 46°16′E], 19.XII.1968, Service Forestier 28492 (holo- : P [P00417679]!; iso- : G [G00014853] image seen, K [K000418833] image seen, MO-5613318!, P [P00417680]!, TEF).
Bourreria moratiana ( J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia moratiana J.S. Mill. in Adansonia ser 3, 25 : 182. 2003.
Typus : Madagascar. Prov. Antsiranana : forêt d'Orangéa, à l'E de Diégo-Suarez, [12°15′S 49°24′E], 25.I.1966, Service Forestier 24435 (holo- : P [P00446404]!;iso- : MO-5613322]!, P [P00417681]!, TEF =[EF000087]).
Bourreria randrianasoloana ( J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia randrianasoloana J.S. Mill. in Adansonia ser 3, 25 : 184. 2003.
Typus : Madagascar. Prov. Toliara : Morondava, forêtd'Antanambao, [20°17′S 44°17′E], 8.II.1956, Service Forestier15554 (holo- : P [P00298610]!; iso- : K [K000975969], MO-6513325!, P [P00298611]!, TEF [EF000179] image seen).
Bourreria schatziana ( J.S. Mill.) J.S. Mill. & Gottschling, comb. nova.
≡ Hilsenbergia schatziana J.S. Mill. in Adansonia ser 3, 25 : 185. 2003.
Typus : Madagascar. Prov. Antsiranana : massif de la Montagne d'Ambre, bassin de la rivière des Makis, 600 m, [12°37′S 49°09′E], 13.X.1954, Service Forestier 11302 (holo- : P [P00298609]!; iso- : MO-5613330!; P [P00446405]!, TEF).
