Meteterakis saotomensis n. sp. (Nematoda: Heterakidae) from Schistometopum thomense (Bocage) (Gymnophiona: Dermophiidae) on São Tomé Island.

Meteterakis saotomensis n. sp. is described from Schistometopum thomense (Bocage), a gymnophionan endemic to the oceanic island of São Tomé in the Gulf of Guinea. The specimens were assigned to Meteterakis Karve, 1930, based on the possession of a head with three rounded lips, not set-off from the body, the absence of interlabia and cordons, females with a long vagina and males with a preanal sucker, surrounded by a cuticularised rim and caudal alae that are supported by fleshy papillae. The new species is characterised by: body length 4.2-4.5 mm (males) and 5.1-6.4 mm (females); total length of oesophagus, including pharyngeal portion and oesophageal bulb, 820-856 µm (males) and 898-1,070 µm (females); length of pharynx 57-58 µm (males) and 65-68 µm (females); spicules equal, 410-521 µm long, with tessellated ornamentation throughout their length and alae, and with bevelled tip; gubernaculum or 'gubernacular mass' absent; tail length 164-176 µm (males) and 214-239 µm (females), with elongated tip; vulva at 2.3-2.8 mm from anterior end, with anterior lip forming small flap. This is the second species of Meteterakis reported from gymnophionan hosts and the first from the Afrotropical region. Selected comparative morphological data for Meteterakis spp. are presented, and data on host range and geographic distribution are updated. The name M. striaturus Oshmarin & Demshin, 1972 is corrected to M. striatura to reflect the female gender of the genus name.