118 NEOTROPICAL PSELAPHIDAE 



Rameloidea 



Only one species appears to belong here, Melba temporalis Raffray, from 

 Martinique (region of St. Pierre). By the four free vertexal foveae this species 

 approaches Ramelbida, but the lateral foveae are not visible from a dorsal 

 view ; the species also shows a relationship to impressifrons , but the tenth anten- 

 nal segment is simply transverse and symmetrical. 



Vertelba 



Here also belongs a single species, Melba caviceps Raffray, from French 

 Guiana. Described on a male, the tibiae are simple, and the length is given as 

 1.00 mm. long. The deep excavation of the head is approached only by Melba 

 impressifrons Raffray, but the tenth antennal segment is not asymmetrical, 

 although described as strongly transverse. 



Key to Quadrelba 



Head simply expanded on each side anterior of the eye; 0.8-0.9 mm. 

 long; St. Thomas and Puerto Rico, Antilles ventricosa 



Head slightly expanded on each side anterior of the eye, and sub- 

 dentate; 0.8-0.9 mm. long; St. Thomas and Puerto Rico, Antilles 

 parmata 



Key to Frontelba 



The following key does not include Melba (Frontelba) fleutiauxi Raffray. 

 The inclusion of David Sharp's two Guatemalan species is questionable in 

 view of the inadequate descriptions and the geographic isolation of the two 

 groups of species. It is wholly possible that these two species belong in Melba 

 s.s. Sharp (1887, p. 38) says that mimula is closely related to clypeata; with 

 respect to his other species, minuta is said to have the head transverse- 

 quadrate (an approach to Quadrelba) but the figure of this species does not 

 show the quadrate head outline expanded anterior of the eyes, and does show 

 the anterior portion of the head expanded between the antennae. Examination 

 of tj'pes will have to resolve these questions. 



Species known from Guatemala 2 



Species known from the Lesser Antilles 3 



2. Head distinctly longer than wide; 1.0 mm. long mimula 



Head as wide or slightly wider than long; 0.8 mm. long minuta 



3. Front produced between the antennae as a semicircular, fiat extension ; 



0.75 mm. long ; St. Thomas clypeata 



Front produced between the antennae, this extension with three 

 tubercles arranged in a triangular pattern; 0.9 mm. long; Gua- 

 deloupe frontalis 



