Published online by Cambridge University Press: 05 June 2009
Mesocoelium malayanum sp.n. is described from the frog Rana macrodon, in Malaysia. Elongate body, broader anteriorly, measuring 1·900 (1·679–2·070) mm long by 0·404 (0·380–0·437) wide, tegument aspinose oral sucker 0·212 (0·200–0·228) by 0·202 (0·191–0·205), acetabulum 0·141 (0·132–0·150) by 0·139 (0·123–0·146), prepharynx present, oesophagus 0·115 (0·096–0·137), caeca reaching posterior ⅓ of body, anterior testis 0·097 (0·087–0·110) by 0·091 (0·087–0·100) dorsal to acetabulum, posterior testis 0·094 (0·087–0·101) by 0·092 (0·091–0·100), cirrus pouch 0·121 (0·111–0·130) by 0·047 (0·041–0·055), genital pore at left of midline of oesophagus just anterior to intestinal bifurcation, ovary 0·110 (0·091–0·127) by 0·089 (0·085–0·096) on left of body and posterior to acetabulum, vitelline glands with single follicles extending from intestinal bifurcation to ends of caeca, excretory vesicle I-shaped and eggs 0·040 (0·037–0·046) by 0·023 (0·022–0·024). Although morphologically related to M. maroccanum and M. meggitti, M. malayanum is considered to be a new species.