Hornschuchia alba

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 : 79-80

publication ID

https://doi.org/10.5852/ejt.2022.828.1859

DOI

https://doi.org/10.5281/zenodo.6828359

persistent identifier

https://treatment.plazi.org/id/03C887E4-0106-FFC4-FDE6-FECEFE1C7D48

treatment provided by

Felipe

scientific name

Hornschuchia alba
status

 

Hornschuchia alba (A.St.-Hil.) R.E.Fr.

Fig. 1 View Fig

Acta Horti Bergiani 10 (2): 137 ( Fries 1931).

Basionym

Bocagea alba A.St. -Hil., Flora Brasiliae meridionalis 1 (2): 42 ( Saint-Hilaire 1825).

Type: BRAZIL – Rio de Janeiro • “ Cabo Frio, Ponta de lʼEst au Cap Frio , Prov. Rio de Janeiro ”; A. Saint-Hilaire 366; holotype: P [ P032535 ]!; isotypes: MPU [ MPU026907 View Materials ]!, S [ S-R-7077 ]! (fragment) .

Material examined

BRAZIL – Rio de Janeiro • “ Armação dos Búzios , Praia Brava . Mata de Encosta Sul voltada para o costão da Praia Brava ”; 24 May 2001; C. Farney 4371; RB [ RB00451923 ]!, SPF ! • “ Costão para João Fernandes. Mata de encosta Praia Brava- Costão para João Fernandes ”; [22°44′38.5″ S, 41°52′17.8″ W]; 23 Aug. 2001; C. Farney 4397; RB [ RB00452010 ]!, SPF GoogleMaps ! • Encosta da Praia Brava ”; 22°44′92″ S, 41°52′40″ W; 18 Feb. 2004; H.G. Dantas 620; RB [ RB00086462 ]! • GoogleMaps ibid.; 22°44′92″ S, 41°52′40″ W; 18 Feb. 2004; H.G. Dantas 156; RB [ RB00086467 ] GoogleMaps ! • “ Rancho Dez ”; Jun. 1997; C. Farney s.n.; RB [ RB00372099 ] ! • “ Fazenda Caravelas ”; alt. 80 m; 20 Oct. 1999; C. Farney 3930; SPF!, RB [ 00452151 ] ! • “ Estrada Cabo Frio- Búzios, entre a Serra das Esmerencias e a Praia de José Gonçalves ”; [22°48′32.8″ S, 41°56′37.8″ W]; 5 Jun. 1998; J.M.A. Braga 4871; RB [ RB00042085 ] GoogleMaps ! • Fazenda of José Gonçalves ”; 22°47′ S, 41°57′ W; alt. 120 m; 8 Feb. 1999; P.J. Maas 8818; NY [ NY02699049 ]!, RB [ RB00042092 ]!, SPF GoogleMaps ! • “ Estrada antiga para Búzios, próximo ao centrinho, ramal da lixeira ”; 28 Jun. 1995; D. Araújo 10320; RB [ RB00417332 ] ! • “ Cabo Frio, Morro da Piaçava ”; 9 Oct. 2002; C. Farney 4487; SPF!, RB [ RB00451944 ] ! • Morro do Mico ”; [22°51′45.4″ S, 42°00′38.5″ W]; 22 Jun. 2002; C. Farney 4463; RB [ RB00451806 ]!, SPF GoogleMaps ! • 27 Aug. 1997; C. Farney 3587; CEPEC [ CEPEC00118741 View Materials ]!, MBM [ MBM325079 View Materials ]!, R [ RB00043047 ]!, SPF!. – Locality unknown • “ E Brasilia ”; Freyreis s.n.; S n.v .

Description

Shrubs, rarely treelets, 2–7 m tall. Leaves chartaceous; petiole 1–3 mm long; lamina 3.8–9.3 × 1.9–4.9 cm, narrowly ovate to ovate or lanceolate, both surfaces glabrous, base acute to obtuse, apex acuminate to acute, obtuse or rounded; primary vein impressed adaxially and raised abaxially, 6–12 pairs of secondary veins, angles between primary and secondary veins 50–60°. Inflorescence one-flowered; supra-axillary, terminal or leaf-opposed, bracts absent. Flowers with pedicel 1–7 mm long; flower buds conical to cylindrical with obtuse apex, 2–8 × 1–3 mm, covered in trichomes. Sepals completely connate, calyx cupuliform, apex truncate, 2 × 2–3 mm, densely covered in trichomes. Petals linear, white, 11–14 mm long, covered in trichomes; stamens 6, ca 2 × 0.5 mm; carpels 3, ca 3 × 0.5 mm. Monocarps 2, immature monocarps fusiform, 4–9 × 3 mm, densely covered in trichomes, mature monocarps obovate, ca 2 cm long ( Saint-Hilaire 1825); stipe ca 1.5 mm long, calyx persistent. Seed ca 6 mm long, ellipsoid, reddish, with fleshy aril ( Saint-Hilaire 1825).

Distribution and habitat

Hornschuchia alba is endemic to Rio de Janeiro State. It is known from only two municipalities, Armação de Búzios and Cabo Frio, occurring in seasonal semideciduous lowland forest ( Mello-Silva et al. 2021; Fig. 1 View Fig ).

Phenology

Flowering from February to October, fruiting from September to October.

Preliminary conservation status

Critically Endangered, CR B1ab(i,ii,iii) ( Amaro 2016). At the time of the last revision of the genus ( Johnson & Murray 1995), only two historical collections of H. alba , including the type, were available. The species was only known with certainty from Cabo Frio. Nowadays there are eight localities, in Armação de Búzios and Cabo Frio, where the species is known to occur. However, H. alba has not been collected in 18 years.

Notes

Johnson & Murray (1995) indicated the holotype as Saint-Hilaire 99. However, this collection number has been assigned to a species of Amaranthaceae Juss. The holotype of Bocagea alba is in fact Saint-Hilaire 366 (Saint-Hilaire’s field notebooks are available at http://hvsh.cria.org.br/works).

There are only immature fruits available (Farney 3930 and 4487), the fruit and seed descriptions have been complemented with the information in Saint-Hilaire (1825). With the new collections of H. alba , the description of the species has been updated ( Johnson & Murray 1995) with new information about the habit and plant size, inflorescence position and flower dimension.

Hornschuchia alba has a single-flowered inflorescence, supra-axillary, terminal or leaf-opposed. It is similar to the specimens of H. myrtillus with this type of inflorescence. However, H. alba is different from H. myrtillus in the leaves that are narrowly ovate to ovate or lanceolate (vs narrowly elliptic to elliptic, oblanceolate to narrowly oblong, obovate or rarely lanceolate) and the pedicel 1–7 mm long (vs 10–28 mm long).

MBM

Myanmar, Yangon, Hlawga Park, Forest Department, Biodiversity Museum

P

Museum National d' Histoire Naturelle, Paris (MNHN) - Vascular Plants

MPU

Université Montpellier 2

S

Department of Botany, Swedish Museum of Natural History

RB

Jardim Botânico do Rio de Janeiro

SPF

Universidade de São Paulo

NY

William and Lynda Steere Herbarium of the New York Botanical Garden

CEPEC

CEPEC, CEPLAC

MBM

San Jose State University, Museum of Birds and Mammals

R

Departamento de Geologia, Universidad de Chile