The Throana group of genera
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Margana Walker Gen. rev.

Type species: seclusalis Walker, Java.

This genus is revived for a small complex of species currently combined with
Egnasia (Poole, 1989). Though the facies and wing shape bear a general similarity to those of Egnasia, the forewing underside has the orbicular stigma conspicuously pale, rather than the reniform.

The two other small Bornean species with a pale orbicular on the underside that were placed in
Egnasia by Poole are assigned to the next two genera. These share this feature of the orbicular and also the lack or considerable reduction of the phragma lobes on the second abdominal tergite, but differ in features of their genitalia. The labial palps in all three genera are long, slender, gently upcurved.

The male eighth segment is atypical, the tergite being slightly framed and the sternite broad, very flimsy, without definite structure. The genitalia have a distinct gnathus that is longer than the uncus. The posterior margins of the tegumen have a central triangular process. The valves are short, obliquely trilobed distally, and there is a distinctive transtilla dorsal to the anellus with prominent digitate processes dorsally in a V. There is also a transverse bridge between the valves ventral to the anellus.

The female genitalia of
tenuilinea Swinhoe (see the taxonomic note for that species) lack the clear features of the Episparis group but share with Throana Walker the dragging of the ostium with the eighth sternite anteriorly into the position of the seventh sternite, which is vestigial to absent. The apodemes of the eighth segment are absent in seclusalis and typical tenuilinea but smaller and pulled anteriorly in the Bornean specimen tentatively associated with tenuilinea.

The ostium is wide, the ductus short, entering almost immediately into a rather elongate corpus bursae that is ornamented with panels of sclerotisation and areas of scobination. Externally similar specimens from Peninsular Malaysia (slide 19246) and W. China (slide 17593) represent further species and have the anterior migration of the ventral part of the eighth segment less extreme, though the seventh sternite is still vestigial. The ductus bursae is longer and narrower in both species (very narrow in 19246), and the corpus bursa more ovate and intensely scobinate. The ductus seminalis arises from near the apex of the corpus bursae.

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