Kanzaki, Natsumi, Giblin-Davis, Robin, Herre, Edward Allen, and Center, Barbara J. 2010. "Redescription of two Panamanian nematodes, Parasitodiplogaster citrinema Poinar & Herre, 1991 and P. popenema Poinar & Herre, 1991 (Nematoda: Diplogastrina)." Nematology 12 (1):89-104. https://doi.org/10.1163/156854109X448366
Parasitodiplogaster citrinema and P. popenema were re-isolated from syconia of Ficus citrifolia and F. popenoei, respectively, from Barro Colorado Island, Panama, and are redescribed and figured herein. Both of these species were previously described as having a "well-developed stoma" and in the case of P. popenema with "stoma slightly longer than wide". Re-examination of fresh material revealed that they share characteristic stomatal morphology, i.e., relatively wide and tube-like stomas with newly observed thorn-like stegostomatal teeth. This is distinctive from the other described Parasitodiplogaster species, which either have a relatively short and narrow stoma with protuberant, claw-like, teeth or a simple cylinder. In addition to the characters of the male papillae arrangement and spicule and gubernaculum morphology, these two species are distinguished from each other by newly-observed lip morphology characters, viz., P. citrinema has three small setae on the outer surface of each lip sector whereas P. popenema has smooth lips. Both P. citrinema and P. popenema appear typologically closest to P. sycophilon, which has a relatively wide and open stoma and seven pairs of male genital papillae, but were distinguished from P. sycophilon by the presence of stegostomatal teeth and the arrangement of the genital papillae.