The gastrointestinal nematodes of Chiruromys forbsei Thomas and C. lamia (Thomas) (Rodentia: Muridae) with the description of a new species of Helgenema (Heligmonellidae) and a new species of Protospirura (Spiruridae) from Papua New Guinea

ABSTRACT The cestode, Bertiella musasabi Yamaguti, 1942 and four nematodes identified to at least genus level and adult specimens assignable to the Nippostrongylinae were recovered from nine of 20 individuals of Chiruromys forbsei Thomas, 1888. Five nematodes identified to at least genus level and adult specimens assignable to the Nippostrongylinae were recovered from 11 of 12 individuals of C. lamia (Thomas, 1897). Species of Parasabanema from C. forbsei and C. lamia, Parastrongyloides from C. lamia and Trichuris also from C. lamia could not be assigned to any known species. Hasanuddinia chiruromyos Smales, 2011a was previously reported from C. vates(Thomas, 1908). Helgenema lamia n. sp. differed from its congener H. keablei Smales, 2020 by its larger size, longer spicules and larger number of eggs in utero. Protospirura munimuniensis n. sp. from C. lamia was differentiated by having two denticles on each pseudolabium, males with the right spicule longer and more robust than the left, a V-shaped gubernaculum and six pairs of post cloacal papillae. Heligmonellids dominated the helminth assemblages of both hosts. Species richness, 80.6% species recovered for C. lamia,and 57% for C. vates was low in both hosts. Possible determinants of species richness were discussed.