Drosera capillaris Poiret (1804: 299)

Gonella, Paulo Minatel, Sano, Paulo Takeo, Rivadavia, Fernando & Fleischmann, Andreas, 2022, A synopsis of the genus Drosera (Droseraceae) in Brazil, Phytotaxa 553 (1), pp. 1-76 : 26-28

6. Drosera capillaris Poiret (1804: 299) . Figures 4b, 10g –i

Type: — USA. Caroline [Carolina], no date, Bosc s.n. (holotype P-00749145!) .

≡ Drosera rotundifolia var. capillaris (Poir.) Eaton & Wright (1840: 230) .

= Drosera tenella Willdenow in Roemer & Schultes (1820: 763).

Lectotype: — VENEZUELA. Sucre: Cumaná, in la Chuchilla de Guanaguana in via Caripensi, Humboldt & Bonpland 216 [B-W06248- 010!, first-step lectotype designated by Duno de Stefano (1995), second-step lectotype designated here; isolectotypes B-100272058!, P-00679675!).

= Drosera tenella Kunth in Humboldt, Bonpland & Kunth (1823: 391), nom. illeg. superfl.

= Drosera brevifolia var. major Hooker (1834: 194) .

Type:— USA. [Louisiana], New Orleans, no date, Drummond 29 (holotype K) .

= Drosera capillaris var. minor Shuttlew. ex Planchon (1848: 194) .

Lectotype (designated here):— USA. Florida : in Bergwiesen bei Monte Vernon [in montane meadows near Mt. Vernon (today’s Chattahoochee)], Aug 1843, F. Rugel 662 (BM-013839833 image!; isolectotypes GH-01143495 image!, RSA-0123640 image!).

≡ Drosera minor [auct. non Schumacher 1827: 167) ] (Shuttlew. ex Planchon) Wood (1861: 251).

= Drosera communis var. breviscapa C.Wright ex Grisebach (1866: 12) .

Lectotype (designated by Correa & Silva 2005 ):— CUBA. Wright 1902 (US-00642066!; isolectotypes BM-000645946!, G-00301950 image!, G-00301949 image!, GH, K-000432525!, MO-2032287!!, NY-00468678!, NY-00468680!).

= Drosera communis var. cubensis Gómez (1890: 223) nom. inval.

Perennial, rosetted, acaulescent. Leaves decumbent, with geniculate-involute vernation, distinctly petiolate, spatulate, sparsely eglandular-pilose mostly on abaxial leaf surface and petiole margins, petioles with narrow lateral wings, lamina suborbicular to obovate; stipule rectangular in outline, divided into laciniate segments from near the base. Scapes with erect base; scapes, pedicels and sepals glabrous (covered by minute sessile glands only); pedicels very short, equal to or shorter than half sepal length; sepals ovate, apex rounded to obtuse, fused up to half length, erect in fruit; petals light pink; gynoecium 3-carpelate, styles bifurcated at the base. Seeds ovoid, testa papillose, papillae arranged in longitudinal rows.

Illustrations: — Diels (1906: 87, figs. 31C–F—leaf, stipule, gynoecium, seed); Hamet (1907: t. II, fig. 10—seed); Silva & Giulietti (1997: 97, figs. 11A–I—habit and details), Duno de Stefano & Culham (1998: 701, fig. 553—habit and leaf).

Distribution: —Widespread in the Americas, albeit showing a disjunct range. It occurs in North America in the southeastern United States and southeastern Mexico; Central America and Antilles in Belize, Honduras, Panama, Cuba, Jamaica, Puerto Rico, Trinidad & Tobago; and in South America in Venezuela, Guyana, Suriname, French Guiana, Brazil (North: AM, AP, PA, RR; Southeast: SP; South: PR, RS, SC; Fig. 4b), and Uruguay. A previous record for Paraguay ( Correa & Silva 2005 ) corresponds to D. communis [specimen Hassler 6807 (MO!, NY!)]. A previous record of “ D. capillaris ” for Costa Rica (Gómez & Gómez-Laurito 1998; Correa & Silva 2005 ) based on the specimen Gómez 25914 (F! USJ image!) corresponds to the Japanese D. tokaiensis ( Komiya & Shibata 1978: 192) Nakamura & Ueda (1991: 136) , based on plant material cultivated at the Jardín Botánico R. & C. Wilson, Las Cruces, Costa Rica (Gómez & Gómez-Laurito 1998); hence a mix-up of field-collected material with the widely cultivated D. tokaiensis seems to have occurred. Therefore, no trustable records of D. capillaris exist for Costa Rica.

Habitat: —In South and Southeast Brazil, D. capillaris is commonly found in large populations on coastal open plain areas in sandy soils (restingas) at sea level, while in North Brazil it occurs in lowland open wet savannas, also in (seasonally) wet sandy soils. Often seen growing as a ruderal in disturbed, wet, oligotrophic areas within its range.

Phenology:—Found with flowers year-round in the tropics.

Conservation status: — Least Concern (LC). Drosera capillaris is widespread and common ( Brazil: AOO= 196 km 2, EOO= 3,676,408 km 2; global: AOO= 2,512 km 2, EOO= 19,306,449 km 2), often observed in disturbed areas as a ruderal. Found inside the National Parks of Jaú (AM), Viruá (RR) and Superagui (PR), as well as the Ilha do Cardoso State Park (SP) and State Forest of Trombetas (PA).

Notes: — Drosera capillaris is morphologically most similar to D. biflora and D. esmeraldae , from which it can be distinguished by characters discussed under D. biflora and outlined in Table 3 . This species further shares with D. intermedia the glabrous scapes, pedicels and sepals, very short pedicels (Fig. 10h), as well as seeds with papillose testa, but can be distinguished (at least in Brazilian specimens) by leaves decumbent with winged petioles and suborbicular to obovate lamina (Fig. 10g; vs. leaves semi-erect, with narrow and not-winged petioles and narrowly obovate lamina), scape with erect base (vs. curved), and seed testa with papillae arranged in longitudinal rows (vs. randomly distributed).

The species presents wide variation regarding overall plant size, leaf orientation and length throughout its entire distribution across the Americas. Two main morphotypes can be recognized: one with upright leaves and long petioles, found only in the northern range of the species, in the USA, Central America and Antilles (fitting the type specimen); and another with compact rosettes, with decumbent leaves and shorter petioles, found more or less throughout the species’ range (Fig. 10g; “fitting Willdenow’s” D. tenella ). Intermediates between the two morphotypes are often found, but in Brazil plants from both the northern and southern distribution ranges are somewhat uniform and fit the D. tenella description and type. Further studies are necessary to evaluate if these two morphotypes represent different taxa or just a single, variable species.

Drosera capillaris var. brasiliensis Diels (1906: 87) was described based on a mixtum of specimens of D. capillaris (e.g., Gaudichaud 267), D. intermedia (Saint-Hilaire B2-204bis), and D. grantsaui Rivadavia (2003: 82) (Glaziou 21121), all of which represent original material. However, the type specimen selected by Diels (1906) clearly represents D. intermedia , having semi-erect leaves with long, narrow petioles and curved base of the scape (see under that species). Therefore, this name is here placed under synonymy of D. intermedia , in discordance with Correa & Silva (2005) .

The designated lectotype of Drosera capillaris var. minor (BM-013839833) is the only one one among the syntypes which has Rugel’s original handwritten label (in German) and the collector’s number, in contrast to the typewritten labels in Latin added by Shuttlewort to all duplicates (which constitute syntypes). Hence, that BM gathering is selected as the lectotype here. Planchon (1848) validated Shuttleworth’s manuscript name “ var. minor ” that was written on the herbarium labels but never had been published by Shuttleworth himself. It is obvious that Planchon studied the material from the respective Rugel gathering in the private herbarium of R.J. Shuttleworth (1810–1874) long before that was distributed post mortem to BM. BM received its set of the Shuttleworth herbarium in 1877 (N. Holstein, pers. comm.), from where duplicates have been distributed to other herbaria.

Wood’s (1861) Drosera minor is a late homonym of Schumacher’s (1827), which is a synonym of D. indica Linnaeus (1753: 282) . Wood’s work “A Class-book of Botany” was first published in 1845 but had several editions over the following years ( Merrill 1948), with the name D. minor only appearing in the 1861 edition.

Drosera communis var. cubensis was published without a diagnosis or a description, failing to meet Art. 38.1 of ICN ( Turland et al. 2018), rendering it an invalid name. For typification of D. tenella , see under D. biflora .

Representative specimens examined: — BRAZIL. Amapá: Oiapoque , Airfield, 25 April 1960, Egler 1418 ( NY) . Amazonas: Parque Nacional de Jaú , 03 September 1998, Vicentini 1371 ( SPF) . PARÁ: Óbidos, FLOTA Trombetas , comunidade Jaramacaru, 11 June 2019, Barbosa-Silva et al. 1129 ( MG) . Paraná: Guaratuba, Brejatuba , 26 October 2013, Barboza 4079 ( MBM) . Guaraqueçaba, PARNA do Superagui , 16 November 2013, Brotto et al. 1437 ( MBM) . Santa Catarina: Insel St. Catharina, 1835, Gaudichaud 267 (B), Torfsümpfe zwischen Pronia comprimida u. São José [peat bogs between...], January 1887, Ule s.n. ( HBG) ; February 1887, Ule s.n. ( US) ; Sümpfe der [bogs of] Campos bei [near] Laguna, January 1889, Ule s.n. ( HBG) ; Florianópolis , 11 September 2004, Rivadavia 1866 ( SPF) . São Paulo: Bertioga, praia de Guaratuba , 05 November 2008, Gonella 176 ( SPF) . Cananéia, Ilha Comprida , 15 April 1987, Falkenberg & Souza 4913 ( FLOR) . Juréia , 11 October 1988, Simão-Bianchini 58 ( SPF) . Rio Grande do Sul: Butiazal de Tapes , Fazenda São Miguel, 28 November 2011, Marchi et al. 3249 (HECT, SPF) . Roraima: Pacaraima , km 685 da BR-174, 25 May 2007, Rivadavia 2563 ( SPF) .