Hoya flagellata Kerr 1940

Type description:

            In Icones Plantarum 35 (1940) t.3407.  Kerr. H. flagellata Kerr; species nova, H. caudatae Hook. f. affinis, foliis floribusque minoribus, corollae lobis pro rata longius caudatis distinguenda.
            Suffrutex epiphyticus; rami graciles, glabri. Folia ovata vel lanceolata, basi rotundata et minute auriculata, apice acute, margine plus minusve revoluta, 4.7‑8.5 cm. longa, 2‑2.5 cm. lata, coriacea, siccitate pallide brunnea, glabra nisi supra interdum pills minutis sparsissime instructa, costa supra subtusque aegre visibili, nervis lateralibus utrinque obscuris; petiolus crassus, rugosus, glaber, 3‑5 mm. longus. Inflorescentia lateralis, pedunculata; pedunculus gracilis, 20‑25 mm. longus, pills deflexo‑patentibus copiose indutus; pedicelli graciles, circiter 9 mm. longi, indumento ut illud pedunculi. Alabastrum apice in cornu circiter 4 mm. longum productum. Calyx  alte 5‑fidus, extus parce pilosus; lobi ovati, longe acute acuminati, apice acuti, 2 mm. longi, basi 0.75 mm. lati. Corolla rotate, subtus glabra, supra marginem versus pills mollibus longiusculis praedita, esplanata circiter 15 mm. diametro; tubus circiter 2 mm. longus; lobi late triangulares, apice in caudam 5 mm. longam producti, cauda exclusa circiter 1.5 mm. longi. Coronae segmenta radiato‑patentia, elliptica, circiter 2.25 mm. longa, supra plana, subtus convexa, angulo inferno in linguam brevem acutam erectam producto, angulo externo subacuto. Antherae appendix membranacea, apice in processum anguste linearem circiter 5 mm. longum producta; corpusculum parvum, ellipticum. Carpella circiter 1.5 mm. alta; stigmatis caput umbonatum, leviter bifidum. Folliculusteres, glaber, leviter striatus, siccitate pallide cinereus maculis fuscopurpureis variatus, apice sensim attenuatus, circiter 7.5 cm. longus, medio 3.5 mm. diametro; semina compressa, circiter 5 mm. longa, 0.75 mm. lata, apice comosa.
            Thailand (Siam). Terutao, edge of mangrove forest, Kerr 14164.
This species is known only from the one, rather scanty collection. It is closely allied to H. caudata Hook. f., found further to the south, in Malacca and Penang. Terutao, the provenance of H. flagellata,is an island on the coast of Satul.—A. F. G. Kerr.

Translation: new species, allied to Hoya caudata Hooker f., leaves and flowers small, lobes of the corolla distinguished by being long caudate in proportion.
            A somewhat woody epiphyte; branches slender, glabrous. Leaves ovate or lanceolate, base rounded and minutely eared, with the apex acute, margine more or less revolute, 4.7 - 8.5 cm. long, 2 - 2.5 cm. wide, leathery, when dry pale brown, glabrous except that above it is sometimes provided with  minute sparse hairs, midrib scarcely visible above, lateral nerves obscure on both sides; petioles thick, wrinkled, glabrous, 3-5 mm. long. Inflorescence lateral, pedunculate; peduncles slender, 20-25 mm. long, clothed with copious flatly deflexed hairs; pedicels slender about 9 mm. long,  with indumentum same as the peduncles. Flower bud with a apical spur 4 mm. long. Calyx  deeply 5 parts, outside sparsely pilose (felt-like); lobes ovate, long acute acuminate, apex acute, 2 mm. long. base 0.75 mm wide. Corolla rotate, glabrous below, above at the margines with long soft pliable hairs flattened about 15 mm. in diameter, tube about 2 mm. long; lobes broadly triangular with a tail like appendage 5 mm. long, exclusive of the tail 1.5 mm. long. With the segments of the corona radiating flatly, elliptic, about 2.25 mm. long. flat above, convex below, with the interior angle tongue like briefly acute produced erect, exterior angle somewhat acute. With the anther appendix membranaceous, apex of the process narrowly linear about 5 mm. long; corpusculum small elliptic. Carpels about 1.5 mm. tall; stigma capitate umbonate, slightly bifid. Follicles round, glabrous, slightly striate, when dry pale ash gray colored with variable spots of brownish purple, apex gradually attenuate, about 1.5 cm. long, in the middle 3.5 cm. in diameter; seeds compressed, about 5 mm. long, 0.75 mm. wide, apex comose.     

Other literature:

            In Florae Siamensis Enumeratio (1951) 36.  W. G. Craib & A. F. G. Kerr. Hoya flagellata Kerr in Hook. Ic. Pl. xxxv. t. 3407 (1940). Puket. Terutao, edge of mangrove forest, Kerr 14164 (type!). This interesting species comes close to Hoya caudata Hook. f., but it has smaller flowers and the corona lobes have relatively longer tails.

            In The Taxonomy and Phytochemistry of the Asclepiadaceae in Tropical Asia (1995) 88.  “The Genus Hoya in Thailand” O. Thaithong. 10. H. flagellata Kerr, Hook. lc. (1840) Pl. XXXV, t. 3407. Fl. Siam. Enum. 3(1) (1951) 36.
            Occurrence: Satun, Trang.
            Notes: Corona purplish red throughout.