144 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 



Larva (pi. 40, fig. 366, and pi. 42, fig. 403). — Total length, 4.6 mm. 

 Length of head capsule i.i times its width. Width of thorax i.i times 

 that of head. Abdominal segments 1-4 slightly narrower than head or 

 thorax; segments 5-7 expanded, at greatest width 1.3 times that of 

 segments 1-4; in profile, like other species of subgenus Lanea; in 

 dorsal view, dumbbell-shaped. General color, greenish gray to tan, 

 with black, comma-shaped patches on ventrolateral areas of segments 

 6-8. 



Head: Designs on frons-clypeus and epicranial plates shown on 

 plate 40, figure 366. Each cephalic fan with 42 pectinate branches, 

 the hairs on these branches all small, bifid, well separated, not inter- 

 spersed with other forms of hairs. Mandible with 2 flattened teeth on 

 its inner margin that appear to arise as branches from the same base ; 

 apical tooth longer and broader than the other. Antenna 310 ju. long, 

 4-segmented, very clear yellow, passes the basal stalk of the cephalic 

 fan; segment i>2<3<4; segments i and 2 with longitudinal stria- 

 tions. Submentum with 9 apical teeth, each in form of a half-hexagon, 

 the central tooth and the outermost tooth on either side larger than the 

 others ; ventrolateral row composed of 3 hairs in straight line, though 

 not equidistant from one another, the hairs bifid near their apices ; 

 lateral margin of submentum deeply serrated, with four toothlike 

 processes. Occipital cleft dome-shaped, with small, nipplelike, apical 

 concavity (pi. 42, fig. 403). 



Thorax and Abdomen : Pseudopod (thoracic proleg) with 20-25 

 rows of hooks at its apex ; postclypeal sclerites absent. Posterior 

 sucker with 71-72 rows of hooks. Anal gills with only 3 main divisions 

 that are fleshy and somewhat tapering, no branching. Anterior arms 

 of X-shaped sclerite with apical winglike expansions along both mar- 

 gins, the posterior arms long and well sclerotized ; no rectal scales. 

 Two minute ventral tubercles on eighth segment ; no pigmented 

 plaques. 



Types. — Holotype (J*) and allotype ($), part mounted on slides, 

 the rest on pins, as well as paratype (^^, $5, and pupae, in the collec- 

 tion of the Instituto de Salubridad y Enfermedades Tropicales, 

 Mexico City; collected in Rio Guayalejo, Xicotencatl, Tamaulipas, 

 Mexico, March 28, 1944. 



SIMULIUM (LANEA) HAEMATOPOTUM Malloch 



Simulium hacmatopotum Malloch, U. S. Dept. Agr. Bur. Ent. Techn. Ser., 

 No. 26, pp. 62-63, 1914 (original description, female). — Vargas, Rev. Inst. 

 Salubr. Enferm. Trop., vol. 3, No. 3, pp. 233-234, figs. 2 and 9, 1942 (c? and $ 

 genitalia). 



