BITING MIDGES — WIRTH AND BLANTON 473 



the dark area proximad of distal spot; branches of media and cubitus 

 narrowly pale margined; pale spot present straddling middle of vein 

 M2; one pale spot, well separated from wing margin, in apex of each of 

 cells Ml, M2, M4 and anal cell, the pale spot in anal cell elongate, 

 another indistinct pale streak in basal portion of anal cell; cell M2 

 with a pale spot lying behind medial fork, one lying in front of medio- 

 cubital fork, and one lying across proximal part of cell and connected 

 with the pale area at basal arculus. Macrotrichia confined to a few 

 in apices of cells R5, Mi and M2; costa extending to 0.55 (0.53-0.56, 

 n=5) of distance to wing tip. Halter whitish. 



Abdomen. — Dark brown, narrow apices of terga with pale gray 

 margins. Spermathecae two, pyriform, unequal, the larger measur- 

 ing 0.053 by 0.036 mm., the bases of the ducts sclerotized a short 

 distance. 



Male genitalia: Ninth sternum with shallow, rounded caudo- 

 median excavation; ninth tergum tapered, with very short apicolateral 

 processes. Basistyle with ventral root foot-shaped, the ankle slender, 

 the heel and toe portions of subequal lengths, dorsal root slender; 

 dististyle strongly bent basally, slender with pointed tip. Aedeagus 

 with short, transverse basal arms, a short, stout, pointed median pro- 

 cess projecting anteriorly from between them; posterior margins of 

 basal arms with short, plate-like expansions; aedeagus bearing poste- 

 riorly a straight, spatulate, distally truncated, dorsal blade with a 

 strong, ventrally curved process arising from the basal arms with its 

 distally pointed tip curving towards the dorsal blade and about two- 

 thirds as long. Parameres each with large, laterally directed, basal 

 knob, stem moderately bent near base, a distinct, triangular projec- 

 tion on mesal side at the site of the bend, nearly straight in midpor- 

 tion, gradually narrowed distally to slender, filiform point. 



Distribution: Panama. 



Panama records: 



Chiriqui Province: Rio Tabasard,. 



CocLE Province: Chiru, El Barrero, El Salado, La Venta, Puerto Farall6n, 



Puerto Obaldia, Rio Hato (type locality). 

 DariiSn Province: Garachin6. 

 Herrera Province: Puerto Chitr^. 

 Panama Province: El Espino, Panamd Viejas, Puerto de Chorrera, Rio Las 



Lajas, San Carlos, Tocumen, Vique Cove. 

 ARCHiPifiLAGO DE LAS Perlas: Isla del Rey. 



Discussion: C. willistoni is confined to the Pacific coast beaches of 

 Panama. It can readily be distinguished from the more widespread 

 phlebotomus (Williston) by the mesonotal pattern of brown dots, pale- 

 ringed legs, and more extensive pale wing spots including narrow pale 

 margins to the veins. 



