Habenaria pseudoculicina J.A.N.Bat. & B.M.Carvalho, 2010

Batista, João A. N., Ramalho, Bruno M. Carvalho Aline J. & Bianchetti, Luciano B., 2010, Three new species of Habenaria (Orchidaceae) from Serra da Canastra, Minas Gerais, Brazil, Phytotaxa 13, pp. 27-39 : 32-34

Habenaria pseudoculicina J.A.N.Bat. & B.M.Carvalho , sp. nov. ( Figs. 2 , 3 )

Ad Habenariam culicinam accedit sed distinguitur foliis patentibus et angustioribus (2–4 mm latitudinem), pedicello longiore (2.7–5.0 mm) et petalorum segmento anteriore proportione breviore (1.7-plo segmenti posterioris longitudinem).

Type:— BRAZIL. Minas Gerais: São Roque de Minas, Parque Nacional da Serra da Canastra, 6.9 km a partir da portaria principal de São Roque de Minas , em direção a Sacramento , cerca de 1.1–1.3 km após a nascente do Rio São Francisco , 20°13'54.5"S, 46°26'36.2"W, 1422 m, 9 January 2007 (fl), Batista, Mota, Faria & Borges 1808 (holotype: BHCB, isotypes: AMES, CEN, MBM, RB, SP) .

Terrestrial herb. Tuber and roots not examined. Stem erect, (10–)18–38(–44) cm long, including the inflorescence, 0.6–1.0(–1.3) mm wide. Leaves 5–7, erect, spreading, widest at the middle, linear, acuminate, (3.5–)5.5–12.0(–16.0) × 0.2–0.4 cm. Inflorescence 5.0–10.5(–13.5) cm long, few to many flowered, onesided; bracts lanceolate, apiculate, 5.0–24.0(–30.0) × 4.1–5.2 mm, about the same size as the ovary and pedicel. Flowers 4–9(–14), green; ovary and pedicel mostly parallel to the rachis, 12–15 mm long, ovary slightly arched, 8.9–10.3 mm long, pedicel 2.7–5.0 mm long. Sepals green, acute, margins smooth; dorsal sepal slightly concave, when flattened ovate, 2.7–4.0 × 2.5–3.0 mm; lateral sepals obliquely falcate, subacute, reflexed, 4.0–5.0 × 1.6–1.8 mm. Petals bipartite, light green, whitish basally, green apically; posterior segment falcate, 2.8–3.8 × 1.0– 1.2 mm, acute, free from the dorsal sepal; anterior segment reflexed, linear-filiform, inserted at the base of the posterior segment, 5.0–6.5 × 0.4–0.5 mm, about 1.7 times as long as the posterior segment. Lip tripartite, basally whitish, apically light green, basal part undivided; side lobes reflexed, linearfiliform, 5.0–7.5 × 0.4–0.5 mm, 1.3 to 1.4 times as long as the midlobe; midlobe linear, slightly recurved, 3.5– 5.0 × 0.8–1.1 mm. Spur slightly projecting forward, totally or partially covered by bracts, slightly clavate, shorter than ovary and pedicel, 8.0– 11.7 mm long, light green, base 0.3–0.5 mm wide, apex 0.7–0.9 mm wide. Column erect, 1.4–1.7 mm long; connective emarginate, green; auricles fleshy, verrucose, whitish, 0.8–1.1 × 0.3–0.6 mm, apex truncate. Anther locules 0.9–1.2 mm long, canals short; hemipollinaria 2, joined by the viscidia. Stigma lobes 2, closely parallel, 1.4–1.6(–2.0) mm long, greenish, receptive part 0.70–0.90 × 0.50– 0.55 mm, flat, turned upwards, obtuse, margins thickened; rostellum 1.1 mm long, greenish; midlobe triangular, fleshy, obtuse, 0.6 mm long, 0.7 mm high, located between the anther locules; side lobes apically convergent, 0.5 mm long.

Distribution:—Known only from Serra da Canastra National Park in southwestern Minas Gerais.

Habitat, ecology and phenology:— Habenaria pseudoculicina grows in seasonally wet meadows, with dark, sandy, shallow soil, frequently associated with rock outcrops. The soil is moist during the rainy season, usually accumulating surface water, but dries to a greater or lesser extent during the dry season. Habenaria pseudoculicina is sympatric with H. psammophila , but prefers wetter sites, whereas the latter is usually found in dryer places at the borders of the moist fields. Flowering occurs from the peak to the end of the rainy season, from January to March. All collections of the species by the authors where made in previously burned areas.

Etymology:—The new species name is a reference to the general similarity with H. culicina .

Conservation status:—Using the World Conservation Union Red List Categories and Criteria ( IUCN, 2001) H. pseudoculicina can tentatively be classified as endangered, due to its limited geographic range [B1ab(iii)+2ab(iii)].

Additional specimens examined:— BRAZIL. Minas Gerais: São Roque de Minas, Parque Nacional da Serra da Canastra, estrada São Roque de Minas - Sacramento , em direção a Sacramento , cerca de 4 km após a portaria São Roque , 12 March 2000 (fl), Batista & Lemos 1062 ( CEN) ; estrada em direção a Cachoeira Casca D’Anta, cerca de 0.7 km após a entrada para a cachoeira a partir da estrada São Roque de Minas - Sacramento , 12 March 2000 (fl), Batista & Lemos 1066 ( CEN) ; área da Babilônia do projeto Tamanduá , 20 March 1990 (fl), Sousa s.n. ( BHCB 17936 ) .

Habenaria pseudoculicina is similar to H. culicina in vegetative and floral morphology. The main distinctive characters are the leaves (spreading and 2–4 mm wide in H. pseudoculicina versus adpressed to the stem and up to 6 mm wide in H. culicina ), length of the pedicel (2.7–5.0 mm long in H. pseudoculicina versus 1.0–2.0 mm long in H. culicina ) and the length of the petal anterior segment relative to the posterior segment (1.7 times as long as the posterior segment in H. pseudoculicina versus 2.3 to 2.6 times as long as the posterior segment in H. culicina ). Other differences are found in the gynostemium: in H. pseudoculicina the column is longer (1.4–1.7 mm versus approximately 1.3 mm in H. culicina ), auricles are smaller than anther locules (versus about the same size in H. culicina ), and the free part of the stigma lobes are turned upwards and perpendicular relative to the anther locules (versus curved forwards and approximately at 180 o with the anther locules in H. culicina ). Lastly, the two species differ in relation to habitat. Habenaria pseudoculicina is typical of seasonally wet meadows (campo limpo estacionalmente úmido), with shallow, dark, sandy soil, whereas H. culicina grows in dry, open, grassy fields (campo limpo seco), grass-herb-subshrub field (campo sujo seco), over deep, well drained, reddish, clay oxisols, and dry campo rupestre (seco).

Habenaria pseudoculicina is also similar to H. canastrensis . Both species are endemic to Serra da Canastra, occur in similar habitats, and flower at approximately the same time. However, they differ in habit (leaves spreading and (3.5–)5.5–12.0(–16.0) cm long in H. pseudoculicina versus adpressed to the stem and 2.5–8.0(–13.0) cm long in H. canastrensis ), length of ovary and pedicel (12.0–15.0 mm long in H. pseudoculicina versus 7.0– 10.5 mm long in H. canastrensis ), length of the lip side lobes (5.0– 7.5 mm in H. pseudoculicina versus 3.0–5.0 mm in H. canastrensis ), and length of the spur (8.0– 11.7 mm in H. pseudoculicina versus 3.7–4.8 mm in H. canastrensis ).

Figures

FIGURE 2. A. General view of Serra da Canastra during the rainy season in January 2007. B. Habitats of H. psammophila and H. pseudoculicina, seasonally wet meadows (campo limpo estacionalmente úmido), on the foreground, and of H. canastrensis, rocky field (campo rupestre), on the background. Flowers from live specimens. Habenaria psammophila. C. Part of inflorescence. D. Flowers. E-F. Habenaria canastrensis. G. Habenaria pseudoculicina. H. H. culicina. Scale bars = 3 mm. C-D. Batista et al. 1794 (BHCB). E-F. Batista & Carvalho 2344 (BHCB). G. Batista et al. 1808 (BHCB). H. Batista 634 (CEN).

FIGURE 3. Distribution of Habenaria psammophila (●), H. pseudoculicina (̝) and H. canastrensis (). The cerrado area is shaded. Areas over 1000 m are indicated by lines. Only one collection was plotted for each locality. Abbreviations for the Brazilian states are: DF, Distrito Federal; GO, Goiás; MG, Minas Gerais.