Celaenorrhinus plagiatus Berger 1976

COCK, MATTHEW J. W. & CONGDON, T. COLIN E., 2011, Observations on the biology of Afrotropical Hesperiidae (Lepidoptera) principally from Kenya. Part 3. Pyrginae: Celaenorrhinini, Zootaxa 3033 (1), pp. 1-67 : 7

Celaenorrhinus plagiatus Berger 1976 ( Figures 1.1 , 2 )

This species was described from Ghana (type locality), Côte d’Ivoire, Nigeria, Cameroon, and Democratic Republic of Congo ( Zaïre) ( Berger 1976). Vuattoux (1999) reared five adults from Hypoestes forskaolii (= verticillaris ) ( Acanthaceae ).

I found it together with C. proxima maesseni in Côte d’Ivoire and reared both, but did not adequately distinguish or document the early stages, which are very similar. I reared C. plagiatus once from caterpillars collected in two-cut shelters on Brillantaisia lamium (MJWC 323 identified by I. Darbyshire, Kew, and MJWC 2010) growing in the shade in Forêt de Yapo, 4 and 10 Dec 1988 (88/203). I did not distinguish the caterpillar from that of C. proxima maesseni , except to note that the white dorsolateral line of the penultimate instar caterpillar ended on A 8 in an orange-red suffusion which extended onto segment A9, whereas the dorsolateral line of C. proxima maesseni simply ended at A8. The head capsule of the final instar measured 3.1 (2.8–3.4) x 2.9 (2.7–3.2) mm wide x high (n=4), and that of the penultimate instar 2.2 (2.15–2.2) x 2.1 (2.07–2.19) mm (n=3). A week after collection, caterpillars accepted Ruellia primuloides (the food plant of 88/208 below), but only one adult was successfully reared through. Three final instar caterpillars were preserved in ethanol.

A two-cut shelter, 14x 15 mm, collected on the same occasion on the same food plant (88/204) contained a dead final instar caterpillar with about 23 Apanteles (s.l.) cocoons just under 3 mm long loosely scattered around it. The dead caterpillar was preserved in ethanol. Five days later, 12 male adult wasps emerged.

Another collection, which was not successfully reared, was made on R. primuloides ( Figure 2.1 ) (MJWC 324 identified by I. Darbyshire, Kew Herbarium, 2010), also in Forêt de Yapo on 4 Dec 1988 (88/208). A final instar caterpillar was found in a two-cut shelter, measuring 22x 20 mm, with a short bridge around a major vein. On 6 Dec, I noted that the caterpillar was 20 mm long; head very dark brown, shiny, rugose; body as 88/203 ( C. plagiatus ), and that it appeared to be full of Apanteles sp. larvae ( Figure 2.2 ). Three days later, on 9 Dec, Apanteles sp. of 88/203 ( C. plagiatus ) from that of C. proxima maesseni , I provisionally treat this caterpillar (88/208) as C. plagiatus . A weak orange suffusion can be seen dorsolaterally on A8 and more strongly on the anal plate ( Figure 2.2 ).

Figures

FIGURE 1. Frontal plates of pupae of Celaenorrhinus proxima group. 1, C. plagiatus female, collected as final instar caterpillar on Brillantaisia lamium, Forêt de Yapo, 4 Dec 1988, 88/203A. 2, C. undescribed nr. dargei male, collected as caterpillar on Mimulopsis solmsii, Kakamega Forest, 16 Jun 1991, 91/35. 3, C. proxima proxima female, collected as pupa on M. solmsii, Kakamega Forest, 1 Sep 1987, 87/20. 4, C. proxima proxima male, collected as caterpillar on Phaulopsis imbricata, Kakamega Forest, 19 Jul 1990, 90/75. 5, C. proxima proxima female, collected as caterpillar on?Acanthopale sp., near Douala airport, Cameroon, 16 Jun 1990, 90/205A. 6, C. proxima maesseni male, collected as caterpillar on unidentified Acanthaceae, Forêt de Yapo, Côte d’Ivoire, 4 Dec 1988, 88/202A (the projection over the eye on the left is crushed out of alignment).

FIGURE 2. Food plant and caterpillar probably of Celaenorrhinus plagiatus but perhaps of C. proxima maesseni. 1, flowering Ruellia primuloides, 4 Dec 1988, Forêt de Yapo, Côte d’Ivoire. 2, final instar caterpillar dorsolateral view, collected 4 Dec 1988 on R. primuloides, Forêt de Yapo, Côte d’Ivoire; photographed 6 Dec; parasitized by Apanteles (s.l.) sp. 9 Dec; 88/208A.