16-17mm. This is a similar species to phlegeusalis in facies, but differs in both male and female genitalia. The male has the bifurcate processes of the valve more equal in shape, the costal one being longer. The sacculus is spined on its inner margin only where it extends as a lobe to associate with the juxta (which is also spined at its apex). The aedeagus has more general spining over its apical part, lacking the spiny subapical process of phlegeusalis, but having similar general scobination over the vesica, coarse over the basal part and finer in a distal zone. The female has the ostium distinctly flask-like with an irregular ostial margin that is deeply cleft ventrally; in phlegeusalis there is a sclerotised pouch surrounding the ostium, and the ductus is less flask-like without a cleft in the ostium. The corpus bursae in phlegeusalis is large, ovate, with one or more zones of scobination on one side that may represent signa, but in the new species the corpus bursae is long, narrow, crinkled and more generally scobinate.
(slide 19755) PENANG: (H.N. Ridley), 1900-113; 1