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