Platylesches galesa Hewitson, 1877

Cock, Matthew J. W. & Congdon, Colin E., 2013, Observations on the Biology of Afrotropical Hesperiidae (Lepidoptera). Part 5. Hesperiinae incertae sedis: Dicotyledon Feeders, Zootaxa 3724 (1), pp. 1-85 : 60-61

Platylesches galesa Hewitson, 1877

This widespread species was described from West Africa ( Hewitson 1877) and reported from Sierra Leone, west to Tanzania and south to Zimbabwe and Mozambique. MJWC encountered this species in Harare, Zimbabwe; he did not see adults, but found a caterpillar (90/200) in the Botanical Gardens on a shoot of Pa. curatellifolia ( Figure 65 ). In TCEC’s experience it is generally a species found in or near forest. Larsen (1991) lists Pl. galesa as a species that might occur in Kenya. Now that the food plant is known it should not be too difficult to track it down where the food plant occurs, if it is a Kenyan species.

Food plants

Murray (1959) states that the food plants in South Africa are Ehrharta erecta and certain other grasses, but as discussed in the introduction to Platylesches , all records from grasses should be discounted. Parinari curatellifolia is now known to be a food plant of Pl. galesa , based on our and others’ observations, but probably first observed by Ivan Bampton in the 1980s. The record from a Parinari sp. by MJWC (pers. comm. T.B. Larsen 1993 in Woodhall 1994) is actually from Pa. curatellifolia in Harare, Zimbabwe (90/200), and not from Kenya. Subsequent authors repeat this food plant ( Pringle et al. 1994, Henning et al. 1997, Heath et al. 2002, Woodhall 2005, Larsen 2005). TCEC has reared Pl. galesa from Pa. curatellifolia in Malawi (Mt. Mulanje) and Tanzania (Rondo Plateau, southeastern Tanzania; Kihansi Gorge, Udzungwa Mts.) and northern Mozambique (Mt. Jao). The record by TCEC from a tall, woody species of Parnari in the Udzungwa Mountains in Tanzania (pers. comm. T.B. Larsen 1993 in Woodhall 1994) is from Pa. excelsa , and TCEC has also reared Pl. galesa from Pa. excelsa at Mt. Mabu, Mozambique.

Ovum

The ova shown in Figure 66.1 were laid on the youngest leaves and stems of flush growth of suckers or saplings of about 1m in the Botanic Gardens, Harare. A final instar caterpillar of Pl. galesa was found at the same time, but adults of Pl. moritili were also flying and the eggs could have been of either species. The living ova ( Figure 66.2 ) are copper-orange in colour and would blend quite well with the hairs of the same colour on young flush growth ( Figure 66.1 ). Once the ova eclose, they are white and quite conspicuous in situ as the newly hatched caterpillar leaves most of the shell uneaten.

Leaf shelters

The mature caterpillar from Harare had made a shelter by folding a leaf downwards along each side of the mid rib and joining the edges. The caterpillar rested on the midrib ( Figure 67.1 ). Feeding was on the apical portion of the leaf and shelter, and in captivity most the leaf shelter was eaten.

Caterpillar

No detailed description was prepared, but the final instar caterpillar from Harare is shown in Figure 67 . The colour and markings of the head of the final instar caterpillar are different from that of any other Platylesches spp. documented so far. Caterpillars documented by TCEC from the Udzungus and Riondo Plateau, Tanzania, and Mt. Mabu, Mozambique, are almost identical.

Pupa

The caterpillar from Harare pupated between a leaf and the base of rearing container, and rather than disturb it, it was not documented.

Figures

FIGURE 65. Shoots of Parinari curatellifolia, Botanic Gardens, Harare, Zimbabwe, 27 Jun 1991.

FIGURE 66. Ova of Platylesches spp. 1, eclosed ova laid on terminal foliage of a shoot of Parinari curatellifolia, Harare, Zimbabwe, 27 Jun 1991 (91/200—a final instar caterpillar of Pl. galesa was found at the same time, but adults of Pl. moritili were also flying and the ova could have been of either species); 2, ovum of Pl. sp. on Pa. curatellifolia, Mgololo, Mufindi, Tanzania, 2 Feb 1998, TCEC (Pl. galesa and other spp. were present).

FIGURE 67. Final instar caterpillar of Platylesches galesa in shelter on Parinari curatellifolia, Harare, Zimbabwe, 27 Jun 1991, 24mm (91/200). 1, dorsal view; 2, anterolateral view of head.