152 BIRDS OF THE REPUBLIC OF PANAMA PART 2 



two smaller screech owls found in Panama, due partly to the few 

 specimens available, has been dissipated through the studies of Joe T. 

 Marshall (West. Found. Vert. Zool., Monogr. 1, 1967, p. 4). His 

 manuscript notes, to which he kindly gave me access, allowed me to 

 identify my specimens and notes without difficulty. 



The Choliba is the more common of the screech owls found in the 

 Republic. Birds of this species on the mainland, where they are 

 widely distributed on the Pacific slope, appear uniform in characters 

 of size and color (variable only in gray and rufescent phases). It has 

 been interesting to find that those of Isla del Rey in the Archipielago 

 de las Perlas agree with the subspecies widespread in northern Colom- 

 bia. Thus there are two forms in the Republic. The species in its 

 entirety ranges from Costa Rica through Panama to Bolivia, northern 

 Argentina, Uruguay, and southeastern Brazil. Several other races in 

 addition to the two found in Panama are recognized. 



OTUS CHOLIBA LUCTISONUS Bangs and Penard 



Otus choliba luctisomis Bangs and Penard, Proc. Biol. Soc. Washington, vol. 34, 

 June 30, 1921, p. 89. (Escazii, Costa Rica.) 



Characters. — Smaller; male, wing 152-165, tail 79-84 mm.; female, 

 wing 155-170, tail 75.0-90.5 mm. ; averaging slightly paler in color on 

 upper surface. 



A male taken January 28, 1962, at Guanico Arriba, Los Santos, had 

 the iris clear yellow ; rim of eyelids dull brown with a yellowish cast ; 

 top of cere and hooked tip of maxilla dull honey yellow ; rest of bill 

 and sides of cere dull greenish gray; bare lower end of tarsus and 

 claws brownish neutral gray. 



Measurements. — Males (6 from Panama), wing 152-165 (158.5), 

 tail 79.9-84.0 (81.4, average of 5), culmen from cere 13.6-14.4 (14.0, 

 average of 5), tarsus 29.5-32.0 (31.1) mm. 



Females (10 from Costa Rica, Panama, and Choco), wing 155-170 

 (162.5), tail 75.0-90.5 (84.9), culmen from cere 13.6-15.9 (14.4), 

 tarsus 31.0-34.8 (33.0) mm. 



Resident. Locally fairly common on the Pacific slope, mainly in 

 the lowlands, from western Chiriqui through the Canal Zone; 

 recorded only as follows : Chiriqui ( Progreso, Divala, Buena Vista 

 above Conception) ; Veraguas (Sona, Chitra) ; Code (Nata, Anton) ; 

 Herrera (Parita) ; Los Santos (Guanico Arriba) ; western Province 

 of Panama (Bejuco) ; Canal Zone (Fort Kobbe, Pedro Miguel, 

 Ancon and Sosa hills, Juan Mina) . 



