Coeliades chalybe chalybe (Westwood)

Cock, Matthew J. W., 2010, Observations on the biology of Afro-tropical Hesperiidae (Lepidoptera) principally from Kenya. Part 1. Introduction and Coeliadinae, Zootaxa 2547, pp. 1-63 : 24-27

Coeliades chalybe chalybe (Westwood) ( Figures 13–17 )

The nominate subspecies was described from the Republic of Guinea and is found in West and central Africa, with an isolated population in the Usambara Mountains, northeast Tanzania. A second subspecies, immaculata Carpenter is restricted to Ethiopia. Although this species is reported from western Kenya, my only observations are from Côte d’Ivoire. The following observations were all made based on my collections 88/211 and 89/204 made on Acridocarpus longifolius (= smeathmannii) ( Malpighiaceae ) at Adiopodoumé, Côte d’Ivoire, 5–6 Dec 1998 and 28 May 1989 respectively.

Adult behaviour

I found this species quite common in the patch of coastal forest at Adiopodoumé. Adult males were observed patrolling along forest paths, settling low down on vegetation to rest. Although wary, they were not very difficult to catch.

Food plants

I found all stages of the life cycle on small plants of a sprawling vine, A. longifolius , growing along a cut path in disturbed forest at Adiopodoumé, Côte d’Ivoire. Other food plants recorded are an unidentified Apocynaceae ( van Someren 1974) , Cynanchum sp. (Apocynaceae) ( Sevastopulo 1975; Kielland 1990) and Marsdenia (Apocynaceae) (A. Atkins in Larsen 1991). Sevastopulo (unpublished) reared C. chalybe in Uganda (Zika Forest, Entebbe) on an unidentified creeper with the underside of its leaves coated with silky pubescence; his description and illustrations of the early stages match mine.

A record from leaves of cacao ( Theobroma cacao ; Malvaceae ) ( Mayné 1917; Smith 1965; Larsen 2005a) was based on a report by M. Ortmans, Directeur de la Société agricole du Mayumbe, and has not been confirmed since. By implication, this observation was made at Mayombe (or Mayumbe, North of Boma, Democratic Republic of the Congo). Mayné (1917, p. 21) records that the pupa is naked, white mixed with reddish, spotted and striped in black (Chrysalide nue, d’un blanc mêlé de rougeâtre, maculée et striée de noir), which matches the pupa of C. chalybe ( Figure 17 ) better than any other species treated here.

Ovum

Ova are laid either at the base, or on the petiole, of one of the terminal leaves of young plants of A. longifolius . Ova are white, hemispherical, with a narrow flattened margin around the base, 1.3mm diameter, with 21–22 ribs ( Figure 13 ).

Caterpillar leaf shelters

I have not seen the first shelters. The second shelters in which 11–13 mm caterpillars were found are made with major cuts across the leaf lamina about two thirds of the way to the apex, leaving the midrib intact, but bared for a further 5 mm beyond these cuts. The shelter is made from the resultant distal portion of dangling, dying leaf, by rolling the cut portions upwards to make a tube, about 20–25mm long by 12–15 mm wide—a type 5 two–cut shelter ( Greeney 2009). The edges, joined with silk, are nibbled to give an irregular margin, and bordered by a row of small (1 mm) holes. The midrib beyond the shelter is also bared, sometimes showing the remains of the first shelter at the apex; this may reflect that there were two more major cuts at the distal end of the shelter, so that this is actually a type 6 four–cut shelter, but further observation would be needed to confirm this. Subsequently there is much feeding on the lamina basal to the shelter.

The third shelters, made by caterpillars of the final two instars, are similar to the stage 2 shelter shown in Figure 14 , and feature one to five 2 mm diameter holes along the edges of the lamina where they are joined to form the shelter.

Caterpillar

Instar n– 2. 11mm. Head just over 1mm wide; light orange-brown; two rows of four spots across face, the upper row stronger. T1 pale with dorsal and dorsolateral black spots; anterior margin yellow-orange; spiracle black. T2–A7 anterior portion, slight over half, black; posterior portion white except for a thin black dorsal line; the white grades into inconspicuous translucent green; ventrally translucent pink. A8 black anteriorly and light orange-brown posteriorly. A9 light orange brown anteriorly with a black dot dorsally on anterior margin; posteriorly two dark bands divided by a pale band; orange spot dorsally on posterior margin. Legs dark; prolegs concolorous. Spiracles pale in black anterior portion of the segment.

A slightly larger caterpillar (13mm) shows the white dorsal areas on segments T2–A7 to be more distinct patches with rounded anterior margins; laterally dark with a white spot around spiracles.

Penultimate instar ( Figure 15 ). 19mm. head orange brown; upper arc of four black spots, central two may be large; lower arc of five black spots, the outer ones over the stemmata. T1 black, posterior margin pale. Body black with white spots; T2–A7 a pair of 1mm white spots on posterior margin, each side of dorsal line, posterior margin of spots truncate; T1–A8 smaller white spot on posterior margin just above leg (when present); T3, A2–A6 small spot near anterior margin, slightly dorsal to last. A8 light orange brown; a black spot dorsally. A9 black. Legs black; prolegs dull brown with black spot. Spiracles inconspicuous.

Final instar. The final instar caterpillars shown in Figure 16 are beautiful and striking—the rich black ground colour of the body contrasting with both the yellow and white-blue spots, and the red-orange head with black spots. The head capsule measures 4.8 x 4.4mm wide x high. No detailed description was prepared. Pupa

The pupal shelter found in the field was formed by drawing together two or three leaves and the pupa was suspended within, held by a Y–shaped girdle. It is white with black spots and streaks ( Figure 17 ), and a 2mm projecting spike at the spiracle T1. No detailed description prepared. The specimen reared by Sevastopulo (unpublished) took 15 days to emerge.

Natural enemies

I reared a gregarious Brachymeria sp. (Chalcididae) from a field collected pupa (88/211; Figure 17 ). Eleven adults, apparently all female, emerged from the mummified pupa 14 days after it was collected, each making a separate exit hole.

Figures

FIGURE 13. Hatched ovum of Coeliades c. chalybe on Acridocarpus longifolius, Adiopodoumé, Côte d’Ivoire, 6 Dec 1988 (88/211).

FIGURE 14. Stage 3 leaf shelter of Coeliades chalybe on Acridocarpus longifolius, Adiopodoumé, Côte d’Ivoire; left, closed shelter; right, open shelter with penultimate instar caterpillar; 6 Dec 1988 (88/211).

FIGURE 15. Penultimate instar caterpillar of Coeliades c. chalybe on Acridocarpus longifolius, Adiopodoumé, Côte d’Ivoire; left, caterpillar 6 Dec 1988 (88/211); right, detail of head 14 Jun 1989 (89/204).

FIGURE 16. Final instar caterpillar of Coeliades c. chalybe on Acridocarpus longifolius, Adiopodoumé, Côte d’Ivoire; left, caterpillar; right, detail of head; 6 Dec 1988 (88/211).

FIGURE 17. Pupa of Coeliades c. chalybe on Acridocarpus longifolius, Adiopodoumé, Côte d’Ivoire, lateral view, 10 Dec 1988 (88/211).