The number of legs in this genus ranges from as few as 16 pairs (e.g., in P. clavigera)[5] to as many as 25 pairs (in P. moseleyi) and varies within species when the number is greater than 18 pairs.[3] Velvet worms in this genus feature a last pair of legs (the genital pair) that is rudimentary or reduced in size, mainly in males. The feet in this genus feature three distal papillae: two anterior and one posterior. The gonopore in the male is cross-shaped but in the female takes the form of a longitudinal slit.[3]
Reproduction
This genus exhibits matrotrophicviviparity, that is, mothers in this genus retain eggs in their uteri and supply nourishment to their embryos, but without any placenta.[6] Eggs are fertilized through dermal insemination.[3] Males place spermatophores on the skin of females, which allows the entry of sperm at the point of contact. Embryonic development in this genus takes 12 to 13 months, during which the mother contains up to 20 embryos, all at about the same stage of development. The young are born alive tail first, one or two at a time, all within a short period of time. The young resemble adults in form but are smaller.[7]
Species
The genus Peripatopsis consists of the following species:
