Birthosea Gen. n.
Type species: bisura Moore
This genus falls within the crescent-signum group. The larva has a configuration
of dorsolateral tubercles as in Setothosea, Setora and Birthamula Hering.
The patterning of the brown forewings is akin to that of Birthamula though
subdorsally in the medial zone there is a dark chevron rather than oblique line.
The bipectinations of the male antennae continue almost to three quarters,
further than in Setora and Setothosea; in Birthamula they
are bipectinate to the apex. The foretibia has no white spot distally.
In the male abdomen the eighth segment bears a moustache-like pair of
hair tufts. The genitalia have the uncus apically bilobed (distal to the ventral
sclerotised spur). The valves bear coarse setae on their internal surface, and
the arms of the furca/juxta are distinctively cornute, associating with a mass
of fine, short, hairlike setae on the anellus.
The female genitalia have a distinctive scobinate lobing and extension
of the eighth segment which is connected to the ovipositor lobes by a
sclerotised tube (below).
The larva is shaped somewhat as in Setora but the longitudinal
section is slightly domed rather than rectangular. Dorsolateral scoli of T3, A1,
A5, A8 and A9 are pronounced, the rest small. The pattern consists of a narrow
dorsal stripe flanked by 'roundels' between the dorsolaterals on A3 and A4; it
is described in more detail in the specific account.
The genus is monotypic.
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