Artitropa usambarae Congdon, Kielland & Collins, 1998

Cock, Matthew J. W., Congdon, T. Colin E. & Collins, Steve C., 2015, Observations on the Biology of Afrotropical Hesperiidae (Lepidoptera). Part 8. Hesperiinae incertae sedis: Dracaena Feeders, Zootaxa 3985 (3), pp. 301-348 : 339-340

Artitropa usambarae Congdon, Kielland & Collins, 1998 (in Congdon & Collins [1998])

This Tanzanian endemic was originally described from a single male reared from Dracaena sp. from Ambangulu in the west Usambara Mountains ( Congdon & Collins 1998), but TCEC and ABRI collectors have since found separate populations in the forests above Mkombola, Nguru Mountains and in the Uluguru Mountains, above Bunduki. It is unusual in that to date, it has only ever been reared and never captured as an adult.

Food plant and life history. TCEC has found the food plant to be D. mannii ; it may also feed on D. steudneri , at least in captivity. A pupa and several caterpillars of this species were found on D. mannii in a small valley on Ambangulu Estate, in deep shade. The caterpillar eats the end of a leaf evenly back towards the base, and rolls a shelter to one side of the cut end of the leaf.

The final instar caterpillar ( Figure 35 ) has a yellow-brown head, with black spots at the top of the adfrontals and adjacent epicranial, two on the epicranium, one above the adfrontals and the other level with the frons, and connecting to a dark line through the anterior stemmata, and another black spot laterally, making seven in total. The markings of the head are darker in the specimen photographed from Nguru Mountains (Figure 35.3), which appears to reflect geographical variation.

The pupa ( Figure 36 ) is similar to others of the genus, with the ground colour pale greenish. However, the dark markings on the head and dorsally on the thorax and abdomen are sharper and more extensive than for other Artitropa spp. There is no white waxy powder on the pupa and only a very thin covering inside the pupal shelter. In Figure 36.2, the thin silken partition at the anterior end of the shelter is very clearly visible.

Figures

FIGURE 35. Final instar caterpillars of Artitropa usambarae, collected on Dracaena mannii [TCEC]. 1, dorsolateral view, Ambangulu, west Usambara Mountains, Tanzania, 9 Jun 2001; 2, dorsal view, as # 1, 12 Jun 2001; 3, head, anterolateral view, Nguru Mountains, 10 Feb 2002; 4 – 5, head and anterior segments, anterolateral view, as # 2.

FIGURE 36. Pupa of Artitropa usambarae, collected on Dracaena mannii, Ambangulu, west Usambara Mountains, Tanzania, 1 Jul 2001 [TCEC]: 1, dorsal view; 2, lateral view.