A new Madagascan species of Hancea Seem. (Euphorbiaceae) Gordon McPHERSON Missouri Botanical Garden, P.O. Box 299, Saint Louis, MO, 63166-0299 (USA) [email protected] McPherson G. 2012. — A new Madagascan species of Hancea Seem. (Euphorbiaceae). Adansonia, sér. 3, 34 (1): 71-75. http://dx.doi.org/10.5252/a2012n1a8 KEY WORDS ABSTRACT Euphorbiaceae, A new species of the genus Hancea Seem. is described from the forested region Acalyphoideae, Hancea, of eastern Madagascar. It can be readily distinguished from the three species Mallotus, previously recognized on the island by the shape of its leaf apex and by its lack Deuteromallotus, Madagascar, of domatia in the axils of the leaf veins. A key to the species of the genus in new species. Madagascar is presented. MOTS CLÉS RÉSUMÉ Euphorbiaceae, Acalyphoideae, Une nouvelle espèce du genre Hancea Seem. (Euphorbiaceae) originaire de Madagascar. Hancea, Une nouvelle espèce du genre Hancea (Euphorbiaceae) est décrite des forêts de Mallotus, l’est de Madagascar. Elle se distingue facilement des trois autres espèces connues Deuteromallotus, Madagascar, de l’île par la forme de l’apex de la feuille et par l’absence de domaties sur les espèce nouvelle. feuilles. Une clé des espèces de Madagascar est donnée. ADANSONIA, sér. 3 • 2012 • 34 (1) © Publications Scientifiques du Muséum national d’Histoire naturelle, Paris. www.adansonia.com 71 McPherson G. INTRODUCTION TYPUS. — Madagascar. Prov. Toamasina, Ambatovy, NE of Moramanga, low, dense forest on lateritic soils, et al 18°51’12”S, 48°18’48”E, 1100 m, 26.II.1998, fl., fr., Recent molecular work by Kulju . (2007) McPherson 17461 (holo-, MO! [#5888427]; iso-, K, on several genera of tribe Acalypheae (subfam- MO!, P, TAN). ily Acalyphoideae) has resulted in the transfer to Hancea Seem. (Sierra et al. 2007) of three endemic PARATYPI. — Madagascar. Prov. Toamasina, parc national Madagascan species previously placed in Deut- de Zahamena, NW de la rivière Moango, 17°33’57”S, 48°53’58”E, 740 m, 24.X.2000, fl., fr., Randriamana- eromallotus Pax & K. Hoffm. or Mallotus Lour. rivo 17 (MO, P, TAN). — Ambatovy, forêt d’Analamay (Leandri 1957; McPherson 1995). This transfer Sud, 18°48’18”S, 48°19’48”E, 1220 m, 18.XII.2004, fl., is supported by morphological characteristics, Andriamahefarivo 47 (MO, P, TAN); idem, 18°48’25”S, primarily type of indument and pollen orna- 48°20’43”E, 1095 m, 9.X.2007, fl., fr., Bernard 602 mentation, and secondarily (because of various (MO, P, TAN); idem, 18°49’25”S, 48°20’04”E, 1068 m, 31.III.2005, fr., Rakotovao 1701 (MO, TAN); idem, degrees of overlap) details of extrafloral nectar- 18°49’58”S, 48°19’46”E, 1061 m, 11.III.2005, fr., Rako- ies, number of staminate flowers per node, type tovao 1614 (MO, P, TAN); idem, 18°50’53”S, 48°18’29”E, of pistillate inflorescence, and spininess of fruits 1124 m, 12.X.2005, fl., Razanatsoa 67 (MO, P, TAN); (Sierra et al. 2006). The Madagascan species, to- idem, 18°51’07”S, 48°17’49”E, 1109 m, 16.II.2005, fl., gether with H. integrifolia (Willd.) S.E.C. Sierra, fr., Rakotovao 1183 (MO, P, TAN); idem, 18°51’22”S, 48°18’34”E, 1141 m, 2.III.2005, fl., Rakotovao 1461 Kulju & Welzen of Mauritius and Reunion, form (MO, TAN); idem, 18°51’24”S, 48°17’41”E, 1000 m, a clade and are placed in the subgenus Cordemoya, 6.III.1997, fl., Rakotomalaza 1258 (MO, P, TEF); idem, while the other 13 recognized species, which are 18°51’34”S, 48°18’25”E, 1050 m, 27.II.1997, fl., Ra- separated by leaf and stipule differences, are East kotomalaza 1196 (MO, P, TEF). — Prov. Fianarantsoa, Asian in distribution and are placed in the type Farafangana, forêt de Manombo, 23°10’12”S, 47°42’50”E, 21 m, 24.III.2004, fl., Ludovic 672 (MO, P, TAN). — subgenus (Sierra et al. 2006, 2007). Prov. Tulear, Fort-Dauphin, forêt d’Ivohibe, 24°34’14”S, A fourth species belonging to subgenus Cor- 047°12’04”E, 265 m, 28.XI.2005, fr., Razakamalala demoya and initially confused with H. spinulosa 2438 (MO, P, TAN); idem, 24°33’52”S, 47°11’43”E, (McPherson) S.E.C. Sierra, Kulju & Welzen first 386 m, XI.2005, fl., Razakamalala 2446 (MO, P, TAN). came to light following recent intensive collect- ing in the Ambatovy region of eastern central DESCRIPTION Madagascar, and it is described below. As well, Small tree 2-8 m; diameter at breast height up to a fifth and a sixth species (H. sp. 1 and 2 in the 12 cm; young twigs glabrous, often resinous near tips; Key) in this group are now known, but from stipules subulate, 1.5-2 mm long, caducous. Leaves fruiting specimens only, and their descriptions opposite to subopposite and unequal, or alternate. thus await collection of staminate and pistillate Blades elliptic-oblong to occasionally ovate, the smaller flowering material. 1.4-6.5 × 0.9-2.8 cm, the larger 2.3-16 × 1.2-4.5 cm, somewhat coriaceous, obtuse to broadly cuneate at the base, typically rather broadly acuminate at the SYstematiCS apex but sometimes merely acute or even obtuse (most often in smallest leaves); midrib raised on both Hancea inhospita McPherson, sp. nov. surfaces, usually pubescent abaxially with erect hairs (Fig. 1) more than 0.5 mm long, but sometimes glabrate or glabrous; secondary veins 8-12 on each side of the mid- Ab ceteris speciebus madagascariensibus cognitis foliis ovatis rib, domatia absent; both surfaces without glandular vel ellipticis domatiis nullis differt. Ab H. spinulosa laminis granules or embedded circular glands, glabrous except foliorum apice late acuminatis vel aliquando obtusis (nec for the midrib abaxially. Shorter petioles 2-25 mm, the anguste acuminatis), nervis in axillis domatiis non instructis, stipulis brevibus (1-2 mm contra 3-5 mm), floribus staminatis longer 4-43 mm, narrowly canaliculate, pulvinate at bracteis brevibus (1 mm contra 1.5-3 mm) et staminibus both ends, often pubescent abaxially like the midrib paucioribus (45-50 contra 80-90) distinguenda. but sometimes glabrate or glabrous. 72 ADANSONIA, sér. 3 • 2012 • 34 (1) A new Madagascan species of Hancea Seem. (Euphorbiaceae) FIG. 1.— Hancea inhospita McPherson, sp. nov.: fruiting branchlets, McPherson 17461, holo-, MO. ADANSONIA, sér. 3 • 2012 • 34 (1) 73 McPherson G. Plants monoecious or (apparently) dioecious. REMARKS Staminate inflorescences racemiform, axillary, The new species differs in leaf shape and apex from 2-5 cm long, resinous-scurfy, flowers solitary along Hancea capuronii (Leandri) S.E.C.Sierra, Kulju the axis or in groups of 2-3, bracts up to 1 mm & Welzen, which is the only Madagascan species long, quickly caducous, pedicels 1-1.5 mm; buds having obovate to oblanceolate leaves with obtuse 1.5-2 mm in diameter; sepals 3-4, 1.5-2.5 mm apices. From the four other Madagascan species long; stamens 45-50 in number. Pistillate inflo- known, H. inhospita is easily distinguished by its rescences axillary; peduncle 2-7 cm long, bearing lack of leaf domatia. It most closely resembles H. a single terminal flower; pedicel c. 1 mm; calyx of spinulosa but differs in having leaves with shorter five subulate sepals 1-3 mm long; styles not seen. and broader tips, in lacking leaf domatia entirely, Fruit c. 6 mm high, 9-10 mm in diameter, minutely and in having shorter stipules (1-2 mm vs 3-5 mm), papillate-granular and puberulent-glabrate, spinu- shorter staminate bracts (1 mm vs 2-3 mm) and lose, each sixth of the capsule bearing one spinule fewer stamens per staminate flower (45-50 vs c. 100). up to 2 mm long. ETYMOLOGY DISTRIBUTION AND ECOLOGY The specific epithet, meaning “not providing shelter”, Hancea inhospita sp. nov. is endemic to the humid was suggested by the fact that Hancea inhospita can evergreen forests of eastern Madagascar on lateritic be most readily separated from its congeners with soils or sand at recorded elevations from 21 to similar leaves by its lack of domatia in the axils of 1220m (Fig. 2). the leaf veins. KEY TO HANCEA SEEM. IN MADAGASCAR 1. Leaves obovate to oblanceolate, the apex obtuse ............................................................ .................................................... H. capuronii (Leandri) S.E.C.Sierra, Kulju & Welzen — Leaves ovate or elliptic, the apex acuminate or acute, rarely obtuse ............................. 2 2. Twigs densely pubescent ............... H. acuminata (Baill.) S.E.C.Sierra, Kulju & Welzen — Twigs glabrous or obscurely puberulent ...................................................................... 3 3. Domatia present in axils of leaf veins .......................................................................... 4 — Domatia absent ......................................................... H. inhospita McPherson, sp. nov. 4. Fruit less than 10 mm in diameter (excluding spinules); spinules up to 4 mm long, 6-c. 24 in number ............................. H. spinulosa (McPherson) S.E.C.Sierra, Kulju & Welzen — Fruit more than 15 mm in diameter (excluding spines); spines 5-15 mm long, more than 25 in number ............................................................................................................. 5 5. Leaf apex long-acuminate; petiole not canaliculate; known only from Ampasindava Pen- insula .............................................................................................................. H. sp. 1 — Leaf apex shortly and broadly acuminate; petiole canaliculate, at least distally; known only from the summit of Mt. Vohimarangitra ................................................. H. sp. 2 74 ADANSONIA, sér. 3 • 2012 • 34 (1) A new Madagascan species of Hancea Seem. (Euphorbiaceae) REFERENCES 45°E 50° CORNET A. 1974. — Essai de cartographie bioclima- tique à Madagascar. Notice explicative 55, ORSTOM, 13.5°S Paris: 1-28. KULJU K. K. M., SIERRA S. E. C., DRAISMA S. G. A., SAMUEL R. & VAN WELZEN P. C. 2007. — Molecu- lar phylogeny of Macaranga, Mallotus, and related genera (Euphorbiaceae s.s.): insights from plastid and nuclear DNA sequence data. American Journal 16° of Botany 94: 1726-1743.