Asketanthera calycosa (A. Rich.) Woodson

Morales, J. Francisco, 2018, Studies in Neotropical Apocynaceae LIV: a synopsis of Asketanthera, Candollea 73 (1), pp. 7-17 : 11

1. Asketanthera calycosa (A. Rich.) Woodson in Ann. Missouri Bot. Gard 19: 47. 1932 ( Fig. 1 , 3 ).

Ξ Echites calycosus A. Rich., Hist. Fis. Cuba, Bot. 2: 94. 1850.

Ξ Rhodocalyx calycosus (A. Rich.) Miers, Apocyn. S. Am. : 140. 1878.

Lectotypus (designated here): CUBA. Prov. Oriente: Santiago de Cuba, 1844, fl., Linden 1783 ( P [ P 00492317]!; isolecto -: BR [BR0000005782482, BR0000005782819]!, GENT!, P [ P03887805 ]!).

 Echites rugelianus Urb., Symb. Antill. 5: 465. 1908. Lectotypus (designated here): CUBA. Prov. Matanzas: Adripas, San Juan river, s.d., fl., Rugel 397 ( NY [NY 111002]!; isolecto -: P!) .

Branchlets moderately to sparsely hirsutulous; interpetiolar colleters up to 0.8 mm long. Petioles 5-10 mm long; leaf blades 7.7-15.1 × 4.8-9.2 cm, ovate, ovate-elliptic to elliptic, the apex acute-mucronate, the base obtuse to rounded, sparsely strigulose on both surfaces, secondary veins impressed on both surfaces. Inflorescence hirsutulous, 8-14-flowered, peduncle 7-20 mm long, pedicels 9-18 mm long, bracts (10-)13-21 × 1.3-7 mm, linearovate, narrowly ovate to ovate-elliptic; sepals (10-)14-21(-28) × 3.5-4.7 mm, narrowly ovate to ovate-elliptic, the apex narrowly acute-mucronate to shortly acuminate, sparsely to moderately hirsutulous externally, the colleter irregularly erose at the apex. Corolla white to creamish white, hirsutulous externally, the indument more dense on floral buds, tube 15-21 × 1.5-3.5 mm, inflated around the stamens, 9-10 mm diam. at the orifice; lobes 28-41 × 12.5-15 mm, obliquely elliptic to ovate-elliptic; stamens inserted in the distal part of the corolla tube, anthers 6.3-6.6 mm long, the auricles acute, style-head 1.7-2 mm long; ovary 1.4-1.5 mm long, glabrous; nectaries c. half the length of the ovary, each nectary irregularly lobed. Follicles 20-34 cm × 5-7 mm, free, densely hirsutulous, continuous; seeds 17-20 mm long, glabrous, coma 1.5-3.3 cm long, cream coloured.

Distribution, habitat and phenology. – Dominican Republic and Cuba, growing in gallery forest and vegetation associated with cliffs at 250-1100 m. Flowering specimens have been collected in January, February, July, August, September, and November, and fruiting in February, August, and September.

Conservation status. – Asketanthera calycosa is known from 16 locations and has an EOO of 109,377 km 2. Forest in many of these places have been reduced to small remnants or have been destroyed. Although the AOO is 44 km 2 and exceeds the value required for an endangered status, more than 50% of the localities analyzed are from outside of protected areas, where A. calycosa is at risk. Asketanthera calycosa is provisionally assessed as “Endangered” [EN B2ab(iii)] according to the IUCN Red List Categories and Criteria ( IUCN, 2012).

Notes. – Asketanthera calycosa may be confused with A. picardae Urb. but can be distinguished by its longer corolla tube and longer corolla lobes and leaf blades obtuse to rounded at the base. The collection from Santo Domingo could represent a mislabeled specimen or with a wrong locality. The duplicate of Linden 1783 deposited at P is designated here as the lectotype because it is better preserved than the other duplicates at BR and GENT herbaria.

Specimens examined. – CUBA. Prov. Camaguey: Cuba oriental, Monte Verde , 17.IX.1860, fl., Wrigth 1377 ( BR, GOET, K, MA, MO, NY, P). Prov. Granma: Bayamesa , Bayamo, II.1889, fr., Eggers 4707 ( CR, K, P, US). Prov. Guantánamo: San Antonio del Sur, Sierra del Purial , cabeceras del arroyo Los Cacaos, 7.IV.1984, Arias et al. s.n. ( JE); Baracoa, Macaguanigua river , 19.I.1915, fl., Ekman 4340 ( S); Maisí, La Tinta, orillas del río Baracoa, entre Guajimero y Alto del Pino, 23.IV.1986, fl. & fr., Genes et al. s.n. ( B, HFC). Prov. Holguin: valley of Cayoguán river, Moa, VII.1949, fl., Alain & Clemente 900 ( US); Sierra de Nipe, El Taller, Piloto river , 3.XI.1914, fl., Ekman 3335 ( S); Sierra de Nipe, El Taller, Piloto river , 18.II.1918, fl., Ekman 9051 ( MO, S); Sierra de Nipe, Barigua river , 30.IX.1922, fl., Ekman 15311 ( S); upper area of Libina river, Sierra del Cristal , 26.VIII.1959, fl., Figueiras 197 ( CR, MO, US). Prov. Las Tunas: Sevilla, Guama river , 3.IX.1906, fl. & fr., Taylor 182 ( JE, NY). Prov. Mayabeque: Sierra Maestro , El Perú, El Perú river , 15.VIII.1922, fl., Ekman 16409 ( MO, S); Pico Turquino , El Perú, 15.VIII.1922, fl., Ekman 14846a ( NY). Prov. Pinar del Río: Sierra de los Órganos, grupo del Rosario, valley of Santa Cruz river, 31.III.1923, ster., Ekman 16390 ( S). Prov. Santiago de Cuba: Sierra Madre, Loma Esperón , 2.VII.1921, ster., Ekman 13037 ( MO, S); Santiago de Cuba, altiplanicie de Santa María del Loreto (Sierra de los Ciegos ), 3.V.1989, fl., Gutiérrez et al. s.n. ( B, HFC). Prov. Villa Clara: Santa Clara, Trinidad mountains, San Blas-Buenos Aires , VIII.1941, fl., fr., Howard 6545 ( JE, NY).

DOMINICAN REPUBLIC. Distrito Nacional: Santo Domingo, s.d., fl., Anon. s.n. ( P-LA n°78).

Figures

Fig. 1. – Asketanthera calycosa (A. Rich.) Woodson.A. Habit; B. Adaxial view of two sepals, showing the colleters at the base; C. Corolla bud;D. Anther, dorsal view; E. Style-head; F. Nectaries and ovary;G. Follicles; H. Seed.

Fig. 3. – Distribution map of the four accepted species in Asketanthera Woodson.