126 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 



Larva. — Not available. 



Types. — Holotype {<^), 4 slides, and allotype ($), 5 slides, in col- 

 lection of United States National Museum. Holotype collected from 

 the Rio Sakcha, Poptum, El Peten, Guatemala, November 11, 1948. 

 Allotype collected from a stream in Coban, Alta Verapaz, Guatemala, 

 November 19, 1944. Paratypes, 3 $$, 4 cj'c?, and 2 pupae, in collection 

 of Herbert T. Dalmat. 



SIMULIUM (LANEA *) CALLIDUM (Dyar and Shannon) 



Eusimuliwn callidum Dyar and Shannon, Proc. U. S. Nat. Mus., vol. 69, 



art. 10, p. 16, fig. 41, 1927 (original description, $). 

 Simulium callidum (Dyar and Shannon), Vargas, Rev. Inst. Salubr. Enferm. 



Trop., vol. 3, No. 3, pp. 231-232, figs, i and 8, 1942 (c? and $ genitalia). — 



Vargas, ibid., vol. 4, No. 4, figs. 28-29, 1943 (pupa). 

 Simulium (Eusimulium) callidum (Dyar and Shannon), Bequaert, in 



Strong, Sandground, Bequaert, and Ochoa, Contr. No. 6, Dept. Trop. 



Med. and Inst. Trop. Biol, and Med., Harvard Univ., pp. 210-212, fig. 98, 



1934 (<?. ?. and pupa). — Vargas, Martinez, and Diaz, Rev. Inst. Salubr. 



Enferm. Trop., vol. 7, No. 3, p. 166-167, 194^ (larva). 



Male (pi. 23, figs. 25-27). — 3.3 mm. long. 



Head : Holoptic. Eyes v^ith upper region shiny reddish brown, the 

 lower region black. Antenna 450 /a long, 11 -segmented, slightly taper- 

 ing ; segment 3 = i -f 2 ; scape and pedicel light brown, flagellum darker. 

 Palpi brown, the base slightly lighter than the rest. Clypeus with 

 silver pruinosity and few long black hairs. 



Thorax: Mesonotum yellowish to orange, with 2 rather narrow 

 longitudinal bands of white pruinosity, one on either side of midline, 

 extending posteriorly for one-third the scutum ; bands curved in form 

 of comma so that the concavity is along the outer margin ; very few 

 yellow scalelike hairs around the periphery, never in packets, seldom 

 visible; short, fine, black hairs over entire mesonotum, somewhat 

 longer in prescutellar region. Humeral angles silvery-pruinose, with 

 fine black hairs and a few golden scalelike hairs. Scutellum light yel- 

 lowish brown, with several long, strong, black hairs and with some 

 slender, appressed, black hairs as well as a few yellow scalelike hairs. 

 Postnotum brown, with silvery pruinosity. Pleura yellow, silvery- 

 pruinose in parts ; pre-alar group primarily black, with i to 2 yellow 

 hairs intermixed. Stem of halter brown, the knob tan. Wings, 3.2 mm. 

 long and 1.4 mm. wide ; relation of body length to wing, i : i ; Sc pilose 

 along basal fifth; Ri with spines along distal three-fifths, with 3 to 

 4 hairs amongst the spines; R2+3 pilose except for very small basal 

 section ; Cu2 arcuate ; discal cell absent. 



* See footnote 6, p. 68. 



