Croton argyrodaphne Baill., Adansonia 1: 146. 1861

Berry, Paul E., Kainulainen, Kent & Ee, Benjamin W. van, 2017, A Nomenclator of Croton (Euphorbiaceae) in Madagascar, the Comoros Archipelago, and the Mascarene Islands, PhytoKeys 90, pp. 1-87 : 14-15

13. Croton argyrodaphne Baill., Adansonia 1: 146. 1861

Oxydectes argyrodaphne (Baill.) Kuntze, Revis. Gen. Pl. 2: 611. 1891. Type. Based on Croton argyrodaphne Baill.

Croton argyrodaphne var. occidentalis Leandri, Ann. Mus. Colon. Marseille, sér. 5, 7(1): 44. 1939, syn. nov. Type. Madagascar. Prov. Mahajanga: région du Cap Saint-André, dunes, 8 Jun 1930, R. Decary 7893 (lectotype, designated here: P [P00127457]!). Madagascar. Prov. Toliara: bassin de la Tsiribihina, Jul 1911, H. Perrier de la Bâthie 9656 (syntypes: P [P00127460]!, P [P00127461]!, P [P00127462]!).]!). Madagascar. Prov. Toliara: Morondava, received 26 Dec 1878, H. Grevé 11 (syntype: P [P00127459]!).

Croton argyrodaphne var. boinensis Leandri, Adansonia, sér. 2, 12: 404. 1972, syn. nov. Type. Madagascar. Prov. Mahajanga: Ampalony, 9 Aug 1971, L.P. Schmitt 515 (holotype: P [P00389629]!).

Croton argyrodaphne var. orientalis Leandri, Adansonia, sér. 2, 12: 404. 1972, syn. nov. Type. Madagascar. Prov. Toamasina: Intendro, près de Fénérive, 9 Jul 1958, Service Forestier 19160-SF (holotype: P [P00418607]!).

Croton vohemarensis Radcl.-Sm., Gen. Croton Madag. Comoro 78. 2016, syn. nov. Type. Madagascar. Prov. Antsiranana: Mantamena, Bekaroaka Range, 7 km N of Daraina (Vohemar), 13°08'S, 49°42'E, 112-330 m, 26 Nov 1990, D. Meyers 206 (holotype: MO!).

Type.

Madagascar. Prov. Antsiranana: Diana Region , Nossibé, 1837, J.M.C. Richard 218 (lectotype, first step designated by Leandri 1972b, pg. 404, second step designated here): P [P00127450]!; isolectotype: K [K001040357] !). Madagascar. Prov. Antsiranana: Diana Region , Nossibé, L.M.A. Du Petit-Thouars s.n. (syntype: P [P00123733]!), ibid. loc., 1837, J.M.C. Richard 571 (syntypes: P [P00127451]!, K [K000347495]!), ibid. loc., 15 Nov 1840, A. Pervillé 236 (syntypes: K [K000347493]!, P [P00127436]!, P [P00127437]!) . Madagascar. Prov. Antsiranana: Loucoubé, 1848, L.H. Boivin 2182 (syntypes: G-DC [G00311741]!, G [G00311741]!, K [K000347494]!, P [P00123729]!, P [P00123730]!, P [P00835716]!) .

Habit and distribution.

Trees to large shrubs; mainly in northern Madagascar, but extending as far south as northern Toliara Province on the west coast and northern Toamasina on the east coast (Antsiranana, Mahajanga, Toamasina, Toliara).

Notes.

Leandri (1972b) designated Richard 218 as the type of Croton argyrodaphne . Given that he did not specify an herbarium in his selection of this collection, we complete the lectotypification here by designating P00127450 as a second-step lectotype. The type of C. argyrodaphne var. orientalis comes from an area in northern Toamasina that is well south of the range of most other C. argyrodaphne specimens. However, there is a second collection of the species from the same area, SF-10816 (TEF), which confirms its occurrence near Fénérive.

The type of Croton vohemarensis consists of two small twigs with leaves that are unusually small and wide for C. argyrodaphne . However, the low stamen number (11) and the characteristic stylar column are very typical of C. argyrodaphne (see Fig. 1E-F ), and it falls within the geographic and altitudinal range for the species. An additional paratype cited by Radcliffe-Smith (2016), Meyers & Bolz 170 (G, MO), comes from the type locality and is a tree 7 m tall, again with unusually wide and long-petiolate leaves for C. argyrodaphne , but it only has young floral buds.

What Leandri recognized as Croton argyrodaphne var. occidentalis is a rather distinctive element of this species, with a western, subcoastal distribution. The plants are small trees, and the leaves have yellowish pigmentation along the midvein on the adaxial leaf surfaces, but other than that they conform well to the general aspect of C. argyrodaphne .

Figures

Figure 1. Diversity of flowers in coppery-lepidote tree species of Croton from Madagascar that are vegetatively very similar. A Croton argyrodaphne, with leaves that are similar to those of several other species B Part of an inflorescence of Croton nobilis showing pistillate flower (below) with thick, reduplicate sepals and no petals, and staminate flower (above) with an intermediate number of stamens (ca. 18) C Staminate flower of C. chrysodaphne, with numerous (ca. 40) stamens and the unusual feature of ten (vs. normally five) petals D Pistillate flower of C. chrysodaphne, with patent, slender bifurcating styles and no petals E Staminate flowers of C. argyrodaphne, with only 11 stamens F Pistillate flower of C. argyrodaphne, with a stylar column topped by tightly bunched, short stigmas and also with recurved petals between the sepals (typically the pistillate flowers of this species are apetalous) G Base of an inflorescence of C. multicostatus showing three open pistillate flowers at the base (with well-developed, ligulate petals) and several open staminate flowers showing a low stamen number of 10 or 11. Photos by P. Berry.