bizonoides Walker comb. n.
bizonoides Walker, 1862, J. Linn. Soc. (Zool.), 6:111.
Diagnosis and taxonomic
note. This is the first of a sequence
of externally very similar species with a rather elongate forewing discal spot
and an antemedial that is more or less fused with, rather than divergent from,
the subbasal over the costal half. These species also share characters of the
male and female genitalia: a deep, almost semicircular uncus, an angled or
spurred saccular margin and spined, reflexed saccular process to the valve, and
a small aedeagus vesica with usually three strong cornuti; two opposed signa
with large spines as discussed in the generic description. The females also have
zones of sclerotisation and scobination in the neck of the bursa with the ductus
and sterigma which may receive the aedeagus cornuti in copulation. No pattern to
this has been detected that could be related satisfactorily to the distinct
types of male genitalia, nor could the development of small (Figs 234, 238-240;
including the type of bizonoides) to large (slides 5254, 5282; Fig
236) lateral pockets on the eighth segment be related with confidence to
structures on the valves of males, though the two specimens with large pockets
could relate to the species with the most robust spining on the saccular process
of the valve, A. sandakan sp. n. Because of this, as indicated in
the generic description, the name bizonoides is applied only tentatively
to the species with two large, rather flattened cornuti and one small one in the
aedeagus vesica, erect, rather triangular subbasal and subapical spines to the
saccular margin and moderate, even spines to the rather small distal saccular
process. One possibly aberrant specimen (slide 5280; Fig 217) has a third large
spine in the aedeagus vesica.
Geographical range. Borneo.
Habitat preference. The
species has been taken from a variety of lowland habitats in Sarawak (alluvial
forest near G. Mulu) and Brunei (coastal forest at Seria, disturbed forest in
the Labi area, heath forest at Telisai). The aberrant specimen was taken in
swamp forest at Badas, Brunei.
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