Astropanax Seem.

Lowry Ii, Porter P., Plunkett, Gregory M., Gostel, Morgan R. & Frodin, David G., 2017, A synopsis of the Afro-Malagasy species previously included in Schefflera (Araliaceae): resurrection of the genera Astropanax and Neocussonia, Candollea 72 (2), pp. 265-282 : 267-268

A. Astropanax Seem. in J. Bot. 3: 174, 176. 1865 ( Fig. 1 ).

Lectotypus (designated here): Astropanax barteri Seem.

= Geopanax Hemsl. in Hooker’s Icon. Pl. 29: tab. 2821. 1909. Typus: Geopanax procumbens Hemsl. (÷ Astropanax procumbens (Hemsl.) Lowry, G.M. Plunkett, Gostel & Frodin ).

Hermaphroditic, unarmed, glabrous (occasionally with indument on twigs and young inflorescence branches), terrestrial, hemi-epiphytic, evergreen trees or rarely lianas. Stems sparsely to well branched or plants monocaulous. Leaves alternate, palmately compound or rarely unifoliolate ( A. monophyllus ); petioles clasping at the base with short to long ligulate stipules; leaflets lanceolate, ovate, elliptical, oblanceolate, or obovate, coriaceous or subcoriaceous to membranaceous, margins entire, crenate, toothed or incised, apex acute to acuminate or caudate (rounded in A. volkensii and sometimes in A. monophyllus ). Inflorescences terminal, erect, paniculate or compound-umbellate, the ultimate units racemose, spicate, umbellate or capitate; inflorescence axes and peduncles subtended by thin bracts (bracts rarely lacking); flowers subtended by bracteoles (or lacking); pedicels slender to stout, unarticulated (flowers sessile in spicate and capitate ultimate units). Ovary inferior, 5-9-carpellate, carpels unilocular, placentation apical; styles 5-9, free or partially or mostly united basally to form a stylopodium or a distinct column. Fruits drupaceous, the disc depressedconcave to flat or short-conical; mesocarp fleshy, endocarp sclerified around each locule, forming a pyrene.

Diversity and distribution. – Astropanax comprises 15 currently recognized species, 11 of which occur in tropical and subtropical Africa, three in Madagascar and one in the Seychelles, along with three as yet undescribed species in Madagascar and possibly one more from Africa. In Africa, the genus extends from Guinea Conakry, Liberia and Sierra Leone in the west, through the Gulf of Guinea Islands and across Central Africa to East Africa, northward to Ethiopia, Somalia and Sudan, and southward to Southern Africa ( Mozambique, South Africa and Swaziland and Zimbabwe). The three Malagasy species of Astropanax occur in humid forests, extending from the far north to the extreme southeastern part of the island, and the single member of the group in the Seychelles is restricted to highly degraded humid forest on the islands of Silhouette and Mahé. Some members of the genus are fairly widespread,

such as A. abyssinicus and A. barteri in Africa ( BAMPS 1974b; APD, 2017) and A. myrianthus in Madagascar ( MADAGASCAR CATALOGUE, 2017), whereas several others have much more restricted geographic ranges, including A. evrardii , A. kivuensis , A stolzii and A. tessmannii in Africa, A. humblotianus in Madagascar, and A. procumbens in the Seychelles.

Notes. – SEEMANN (1865) included five species in his new genus ( A. abyssinicus , A. baikiei , A. barteri , A. elatus , and A. mannii ), the second and fourth of which have been placed in synonymy by most recent authors (cf. BAMPS 1974a, 1974b; FRODIN & GOVAERTS, 2004). Our recent molecular phylogenetic studies ( GOSTEL et al., 2017) include samples of S. barteri and S. mannii and place both within a clade that corresponds to Astropanax .

We have selected as the lectotype of the genus Astropanax barteri [Barter s.n., K!] because it is the best known and most widely distributed of the three accepted species originally assigned to the genus by SEEMANN (1865) .

Figures

Fig. 1. – Photographs of Astropanax Seem. A. Astropanax monophyllus (Baker) Lowry, G.M. Plunkett, Gostel & Frodin; B. Astropanax myrianthus (Baker) Lowry, G.M. Plunkett, Gostel & Frodin; C. Astropanax barteri Seem.; D. Astropanax mannii (Hook.f.) Seem.; E. Astropanax stolzii (Harms) Lowry, G.M. Plunkett, Gostel & Frodin; F. Astropanax volkensii (Harms) Lowry, G.M. Plunkett, Gostel & Frodin.