First Male Hologerrhum philippinum Found on Luzon
The genus Hologerrhum is one of four endemic snake genera found only in the Philippines. Because there were no male specimens of H. philippinum in collections, taxonomists thought this might have been an all-female, parthenogenetic species which could reproduce without the presence of a male. During recent fieldwork in the northern Philippines, an adult male H. philippinum was collected in mixed primary- and secondary-growth forest, under a rock in a dry river bed, in the Angat Dam Watershed Reserve on Luzon Island. This is the first known reproductively mature male specimen of this species; the only other male was a juvenile with its reproductive organs retracted into its body.
Phenix, E., J. Phenix, C.D. Siler, R.M. Brown, A.C. Brown. 2011. Hologerrhum philippinum (Philippine Stripe-lipped Snake). Reproduction. Herpetological Review 42(4): 614. pdf