placed genus in tribe Polidrepanini. Delarthrum Attems, 1936 has hitherto remained
monobasic, with D. obscurum Attems, 1936, from Pun-
jab, Pakistan being the type, and sole, species [Attems,
1936]. Jeekel [1980a] first allocated this genus in the
tribe Polydrepanini, putting emphasis on a well-devel-
oped and elongate gonopod femorite, versus a strongly
abbreviated one observed in Alogolykini, the second
constituent tribe of the subfamily Alogolykinae. A lit-
tle later, however, Jeekel [1980b] reshaped both these
tribes and assigned Delarthrum to the Alogolykini on
account of an untwisted gonofemorite which retains the
seminal groove running on its mesal side alone, versus
a strongly twisted, helicoid femorite supporting the
seminal groove largely on the lateral side as seen in the
Polydrepanini. Both tribes have recently been rede-
fined: a strong, rod-shaped solenomere versus a thin,
flagelliform one remains the basic difference between
the tribes Alogolykini and Polydrepanini, respectively
[Likhitrakarn et al., 2013]. This distinction, however, is
often far from clear-cut. For instance, numerous species
of Alogolykinae demonstrate slender, but ribbon-shaped
solenomeres which are kind of intermediate between
really thick and rod-like, on the one hand, and clearly
flagelli- or filiform conditions, on the other hand.