Hornschuchia obliqua Maas & Setten

Vilela, Lucas & Lopes, Jenifer De Carvalho, 2022, Hornschuchia (Annonaceae), an endemic and threatened genus from the Brazilian Atlantic Forest, European Journal of Taxonomy 828, pp. 75-108 : 96-97

Hornschuchia obliqua Maas & Setten

Figs 4D , 5

Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen, Series C: Biological and Medical Sciences 91 (3): 260, figs 18–19 ( Maas et al. 1988).

Type : BRAZIL – Bahia • “ Cairu, Estrada Cairu-Ituberá, 8 km S de Cairu ”; [13°34′22.4″ S, 39°03′22.6″ W]; 26 Jul. 1981; A.M. Carvalho 798; holotype: CEPEC [ CEPEC00024357 ]!; isotypes: CEPEC [ CEPEC00050811 ]!, NY [ NY00008356 ]!, U [ U0000334 ] !.

Material examined

BRAZIL – Bahia •“ Ilhéus, Distrito de Castelo Novo, fazenda Almada , coletas no km 4na estrada para estação experimental do Almada e o povoado de Ribeira das Pedras, entrada no km 20 da rodovia Ilhéus/Uruçuca ”; [14°39′18.7″ S, 39°11′16.4″ W]; alt. 110 m; 8 Feb. 1996; L.A.M. Silva 3355; CEPEC [ CEPEC00070901 ] ! • “ Uruçuca, Distrito de Serra Grande, 7.3 km na estrada Serra Grande/Itacaré, Fazenda Lagoa do Conjunto Fazenda Santa Cruz ”; 14°25′23″ S, 39°3′42″ W; 11–21 Sep. 1991; A.M. de Carvalho et al. 3602; CEPEC [ CEPEC00052187 ]!, HUEFS [ HUEFS013892 ]!, MBM [ MBM158839 ]!, NY [ NY00395805 ]!, US [ US01346587 ] ! • ibid.; 14°25′24″ S, 39°3′38″ W; 15 Nov. 1995; W.W. Thomas et al. 11019; ALCB [ ALCB004564 ]!, CEPEC [ CEPEC00068119 ]!, MBM [ MBM194749 ] ! • ibid.; 14°25′ S, 39°01′ W; 7 Sep. 1991; A.M. de Carvalho et al. 3649; CEPEC [ CEPEC00052143 ]!, HUEFS [ HUEFS013893 ]!, MBM [ MBM158840 ]!, NY [ NY00395807 ] ! • ibid.; 1–12 Jul. 1991; W.W. Thomas 8041; NY [ NY00395804 ] ! • ibid.; 1–12 Jul. 1991; A.M. de Carvalho 3350; ALCB [ ALCB004359 ]!, CEPEC [ CEPEC00052214 ]!, NY [ NY00395806 ]!, RB [ RB01351907 ]!, US [ US01346588 ] ! • ibid.; 6 Oct. 1992; A.M. Amorim 794; CEPEC [ CEPEC00056662 , NY [ 00395802 ]!, NY [ NY00395803 ]!, RB [ RB00042097 ]!, US [ US01346586 ] ! • ibid.; 1–12 Jul. 1991; W.W. Thomas 6933; CEPEC [ CEPEC0005328 ] ! • ibid., “ 7 km na estrada Serra Grande/Itacaré, local do Inventário Florestal ”; 10 Oct. 1995; A.M. de Carvalho et al. 6132; CEPEC [ CEPEC00066687 ]!, MBM [ MBM187066 ]!, NY [ NY00395801 ] ! • ibid., “ rodovia BA-001 Ilhéus/ Itacaré, ca 4.5 km do distrito de Serra Grande ”; 5 Jul. 2001; J.G. Jardim 3721; NY [ NY00684332 ] !.

Description

Shrubs or trees, 1.5–8 m tall. Leaves chartaceous, petiole 1–3 mm long, lamina 12–31.5 × 3.6–10.3 cm, oblanceolate to narrowly oblong or narrowly elliptic, both surfaces glabrous, base asymmetric or cuneate, apex acuminate, acute, attenuate, primary vein impressed adaxially and raised abaxially, 9–18 pairs of secondary veins, angles between primary and secondary veins 30–45°. Inflorescence 3–8-flowered, in shortened, highly ramified branches, terminal or supra-axillary, bracts rarely persistent, 1.0–1.3 × 0.4–0.5 cm. Flowers with pedicel 3–30 mm long, flower buds 3–6 × 1–2 mm, cylindrical with obtuse apex, covered in trichomes. Sepals completely connate, calyx cupuliform, apex truncate, 2–4 × 1–4 mm, glabrescent. Petals linear, white, 7–7.5 mm long, glabrous, stamens 6, 2.5–3 × 0.5 mm, carpels 3, 2.4–3 × 0.5 mm. Monocarps 1–2, fusiform, 15–45 × 5–8 mm, densely covered in trichomes, immature monocarps whitish in vivo, sessile. Seeds 1–2.

Distribution and habitat

Hornschuchia obliqua is endemic to Bahia, where it occurs in lowland tropical moist forest ( Gouvêa et al. 1976; Thomas & Barbosa 2008; Fig. 5 ).

Phenology

Flowering from February to October, fruiting from July to November.

Conservation status

Endangered, EN B1ab(i,ii,iii)+2ab(i,ii,iii) ( Amorim et al. 2020b). Hornschuchia obliqua is only known from three localities. It has not been collected in 19 years.

Notes

Hornschuchia obliqua and H. santosii have 3–12-flowered inflorescences, which are axillary, terminal ( Fig. 4D ) or leaf-opposed. However, H. obliqua differs from H. santosii by its cylindrical floral bud (vs conical), fusiform monocarp, 1.3–6 mm wide, densely covered in trichomes and whitish in vivo (vs globose, 16–19 mm wide, glabrous, green in vivo; Fig. 4E ). The description of H. myrtillus has been updated ( Johnson & Murray 1995) with information regard the plant size and fruit dimensions.

Figures

Fig. 4. Morphological characters of some species of Hornschuchia Nees. A. H. citriodora D.M.Johnson, branch with flower (J. Kallunki 342, SPF). B–C. H. mediterranea Mello-Silva & D.M.Johnson (W. Thomas 12313, NY). B. Floral bud. C. Flower. D. H. obliqua Maas & Setten, branch with terminal ramified inflorescence (A.M. Carvalho 798, NY). E. H. santosii D.M.Johnson, monocarp (P. Fiaschi 1226, SPF). Drawing by Laura Montserrat.

Fig. 5. Geographical distribution of Hornschuchia mediterranea Mello-Silva & D.M.Johnson, H. myrtillus Nees and H. obliqua Maas & Setten. Abbreviations: BA = Bahia; ES = Espírito Santo.