FAMILY TROGLODYTIDAE 



73 



THRYOTHORUS MODESTUS ZELEDONI (Ridgway J 



Thryophilus zeledoni (Lawrence Ms.) Ridgway, Proc. U.S. Nat. Mus., vol. 1, 

 1878, p. 252. (Pacuare, Limon, Costa Rica.) 



Characters. — Similar to Thryothorus modestus elutus (Bangs), but 

 larger and decidedly darker; dorsal surface, sides, flanks, and undertail 

 coverts gray (without definite reddish brown markings); bill and feet 

 larger, stronger. 



Kennard recorded a female taken at Almirante as having the maxilla 

 black; mandible yellow; iris gray-brown; tarsus dark olive. 



Measurements. — Males (10 from Bocas del Toro, Costa Rica, and 

 Nicaragua), wing 62.3-65.0 (63.5), tail 49.4-53.9 (51.5) , culmen from 

 base 19.5-22.5 (21.1), tarsus 24.8-26.6 (25.8) mm. 



Females (9 from Bocas del Toro and Costa Rica), wing 60.0-63.3 

 (61.7), tail 48.5-51.5 (48.6), culmen from base 17.4-21.5 (19.9), tar- 

 sus 24.2-25.8 (25.0, average of 8) mm. 



Resident. Recorded in the lowlands of western Bocas del Toro, 

 from Almirante, Isla Colon in Almirante Bay, and Zegla on the Rio 

 Changuinola to the Costa Rican boundary on the lower Rio Sixaola; 

 not abundant. 



This wren was described originally by Ridgway as a distinct species, 

 from its larger size and darker coloration compared to Thryothorus 

 modestus, and was so treated by Salvin and Godman in 1880, Sharpe in 

 1881, Carriker in 1910, Kennard and Peters in 1931. Hellmayr, how- 

 ever, (Cat. Birds Amer., pt. VII, 1937, pp. 170-171), from examina- 

 tion of 4 specimens from Matina, Limon, and La Iberia Farm on the 

 base of Volcan de Turrialba, Costa Rica, placed it as a race of Thryo- 

 thorus modestus with the statement that though "well characterized by 

 much larger feet and bill, much duller and less brownish upper parts 

 with brownish instead of rufescent wings and tail, and much less ful- 

 vous flanks and undertail coverts ... is clearly conspecific with T. 

 modestus . . . though intergradation, especially in dimensions, is far 

 from being complete." Hellmayr's action has been followed, mainly 

 uncritically, since. 



Carriker (Ann. Carnegie Mus., vol. 6, no. 4, 1910, p. 755), in writing 

 of Costa Rica, said of zeledoni that he first encountered it "along the 

 Sicsola [= Sixaola] River, where they frequented wild-cane brakes and 

 a high tangled grass found only along the river bank, known as 'gami- 

 lote.' " He never saw it in forest. His locality was along the present 

 northeastern end of the boundary with Panama. 



