Hornschuchia (Annonaceae), an endemic and threatened genus from the Brazilian Atlantic Forest Vilela, Lucas Lopes, Jenifer De Carvalho European Journal of Taxonomy 2022 2022-07-11 828 75 108 3MPYW D. M. Johnson D. M. Johnson [574,1013,644,671] Magnoliopsida Annonaceae Hornschuchia Plantae Magnoliales 24 99 Tracheophyta species santosii   Figs 4E, 6   Brittonia47 (3): 303, fig. 24 ( Johnson & Murray 1995).     Type: BRAZIL–  Bahia• ( Teixeira de Freitas*),  “Km 6 da rod. Teixeira de Freitas a Alcobaça”; [ 17°31′05.6″ S, 39°39′07.3″ W];  9 Oct. 1971;  T.S. dos Santos2091; holotype: CEPEC[ CEPEC00007576]!; isotype: NY[ NY00008357]!.   Material examined   BRAZIL–  Bahia• “Buerarema, Rodovia que liga Buerarema a Vila Brasil, km 14”; [ 15°03′40.9″ S, 39°14′28.1″W];  9Feb.1982;  A.M.de Carvalho1172; CEPEC[ CEPEC00028511]!, HEPH[ HEPH00001089]!, NY[ NY00395773]! • ibid.;  9 Feb. 1982;  A.M. de Carvalho1175; CEPEC n.v., HEPH[ HEPH00001087]! • “ Canavieiras” ( Santa Luzia*); 15º22′ S, 39º11′ W; alt.  100 m;  15 Aug. 1984;  M.M. Santos169; CEPEC[ CEPEC00037788]! • “ Santa Luzia, Vila São João. Reserva de mata do CEPLAC, entrada em bifurcação à direita da estrada Santa Luzia-Vila São João, 18, 5 kmalém do rio na saída de Santa Luzia, 4.6 kmalém da bifurcação e 1 kmalém de ponte de concreto da reserva”; 15º23′18.2″ S, 39º12′04.9″ W; alt.  97 m;  26 Oct. 2008;  R. Mello-Silvaet al. 3134; SPF! • “ Una” ( Santa Luzia*), “Estrada de Una para Santa Luzia, ca 1 kmapós a Vila São João, ca 20 kmde Una, ramal à esquerda”; 15º23′ S, 39º12′ W;  4 Dec. 2002;  P. Fiaschi1226; CEPEC[ CEPEC00094181]!, CEPEC00094205]!, NY[ NY01806300]!, RB[ RB00484635]!, SPF!.    Description Shrubs or trees, 2–7 mtall. Leaves chartaceous, petiole 1–5 mmlong, lamina 8.6–20.5(–25.7) × 2.8– 9.8 cm, narrowly oblong to elliptic, narrowly obovate to oblanceolate or narrowly ovate, both surfaces glabrous, base cuneate, rounded to obtuse, apex attenuate to acute or obtuse, primary vein impressed adaxially and raised abaxially, 9–14 pairs of secondary veins, raised adaxially, angles between primary and secondary veins 40–60°. Inflorescence 4–12-flowered in highly ramified branches, axillary, terminal or leaf-opposed, bracts absent. Flowers with pedicel 2–25 mmlong, flower buds 4–9 × 1.5–3 mm, conical with rounded apex, covered in trichomes. Sepals completely connate, calyx cupuliform, apex truncate, 1–3 × 3–5 mm, densely covered in trichomes. Petals linear, white, 9–22 mmlong, covered in trichomes, stamens 6–18, 2–3.5 × 0.5 mm, carpels 2–9, 1–3 × 0.5 mm. Monocarps 1–3, globose to ovoid with rounded to acute apex, 21–22 × 16–19 mm, glabrous, stipe 1.5 mmlong, calyx persistent. Seeds 6–8, 12–15 × 7–8 mm, flattened ellipsoid with aril.    Distribution and habitat   Hornschuchia santosiiis endemic to Bahia, only known from three localities, the municipalities of Buerarema, Santa Luzia and Teixeira de Freitas. The only records in the municipalities of Canavieiras, Santos 169, and Una, Fiaschi 1226, have their geographic coordinates in Santa Luzia, in the same place of the collection Mello-Silva 3134. This region is close to the border of these three municipalities; therefore, it is possible that the collections Santos 169and Fiaschi 1226were made in Santa Luzia. The species inhabits lowland tropical moist forest ( Gouvêa et al.1976; Thomas& Barbosa 2008; Fig. 6).    Phenology Flowering from February to December, fruiting in December.    Preliminary conservations status   Hornschuchia santosiihas an EOO of 1378 km 2and an AOO of 12 km 2. It has been found at three localities, one of them in a conservation unit. It has not been collected in 10 years. Moreover, as already mentioned, the region  H. santosiiinhabits is endangered due to deforestation ( Landau et al.2008). Therefore, it should be considered Endangered, EN B1ab(iii)+2ab(iii), according to IUCN Red List Categories and Criteria( IUCN 2012).    Notes   Hornschuchia santosiiis the only species with up to 18 stamens and 9 carpels, it is similar to  H. obliqua, the note under the latter describes the differences between them.   Distribution, endemism and conservation   Hornschuchiais a threatened genus, 11 of its 12 species are classified either as Critically Endangered, Endangered or Vulnerable. Only  H. bryothopheis categorized as of Least Concern following the IUCN criteria ( IUCN 2012) ( Table 1). We have inferred the conservation status of five species:  H. citriodora,  H. leptandra,  H. linanarum,  H. polyanthaand  H. santosii, all classified as Endangered. The remaining species have already been classified. One species is Critically Endangered,  H. alba, nine species are Endangered:  H. cauliflora,  H. citriodora,  H. leptandra,  H. lianarum,  H. mediterranea,  H. mellosilvae,  H. obliqua,  H. polyanthaand  H. santosii, while one is Vulnerable,  H. myrtillus( Table 1). Seven species are known from only five or fewer localities:  H. citriodora,  H. leptandra,  H. lianarum,  H. mediterranea,  H. mellosilvae,  H. obliquaand  H. santosii( Table 1). Four species have not been collected in more than 17 years:  H. alba,  H. leptandra,  H. mellosilvaeand  H. obliqua. Only four species are found in conservation units:  H. bryotrophe,  H. citriodora,  H. leptandraand  H. myrtillus.   Hornschuchiais endemic to the Brazilian Atlantic Forest, as defined by law (  Brasil2006), occurring from the State of Pernambucoto Rio de Janeiro( Fig. 7A). The species with the widest distribution is  H. bryotrophewith a single collection in Pernambuco, its main distribution is from Bahiato Rio de Janeiro( Fig. 1). One species is endemic to Rio de Janeiro,  H. alba( Fig. 1). Seven species are endemic to Bahia:  H. cauliflora,  H. leptandra,  H. mediterranea,  H. mellosilvae,  H. polyantha,  H. obliquaand  H. santosii( Figs 3, 5–6). Most species occur in moist lowland tropical forest. Eight species also occur in seasonal semideciduous forest:  H. alba,  H. bryotrophe,  H. cauliflora,  H. leptandra,  H. lianarum,  H. mediterranea,  H. mellosilvaeand  H. myrtillus( Figs 1, 3, 5–6).  Hornschuchia lianarumand  H. mediterraneareach the seasonal deciduous forest of Bahiaand are the only species occurring in this typeof vegetation ( Figs 3, 5). Southern Bahiais the centre of species richness for  Hornschuchia(8 spp.); followed by northern Bahia(4 spp.) and northern Espírito Santo(3 spp.; Fig. 7B). Southern Bahia, the region close to Ilhéus, is also where most of the specimens have been collected, ranging from 13 to 18 records per cell ( Fig. 7C). The second region where most of the species have been collected is Espírito Santo, close to Linhares, with eight records per cell ( Fig. 7C). The total points of occurrence for the species of  Hornschuchiawere 105. Two bioregions were identified, one including the coast of Bahiaand northern Espírito Santo, bioregion 1; the other encompassing Rio de Janeiroand southern Espírito Santo, bioregion 2 ( Fig. 7D, Table 2). Nine species are the most indicative for bioregion 1:  Hornschuchia bryotrophe,  H. cauliflora,  H. polyantha,  H. leptandra,  H. lianarum,  H. mediterranea,  H. mellosilvae,  H. obliquaand  H. santosii( Table 2, Fig. 7D). In bioregion 2, the most indicative species are  H. alba,  H. citriodoraand  H. bryotrophe( Table 2, Fig. 7D). 3862607480 [839,1394,743,770] de Freitas Brazil Teixeira de Freitas 24 99 1 Bahia type 3862607382 1971-10-09 CEPEC, NY T. S. dos Santos Brazil -17.518223 Teixeira de Freitas 1 -39.65203 24 99 CEPEC00007576, NY00008357 1 Bahia holotype 3862607332 1982-02-09 CEPEC, HEPH, NY A. M. de Carvalho Brazil -15.061361 Bahia 1 -39.24114 24 99 CEPEC00028511, HEPH00001089, NY00395773 1 Bahia 3862607455 [442,1396,990,1017] 1982-02-09 CEPEC, HEPH A. M. de Carvalho Brazil -15.061361 Bahia 1 -39.24114 24 99 HEPH00001087 1 Bahia 3862607338 1984-08-15 CEPEC M. M. Santos Brazil 100 -15.366667 Canavieiras 1285 -39.183334 24 99 CEPEC00037788 1 Bahia 3862607353 2008-10-26 SPF R. Mello-Silva Brazil 97 -15.388389 Vila Sao Joao 1 -39.201363 Santa Luzia 24 99 1 Bahia 3862607383 2002-12-04 CEPEC, NY, RB, SPF P. Fiaschi Brazil -15.383333 Una 1285 -39.2 24 99 CEPEC00094181, CEPEC00094205, NY01806300, RB00484635 1 Bahia