Birds of North and Middle America, part V/Genus 13. Ramphocænus Vieillot

by Robert Ridgway

 

Genus RAMPHOCÆNUS Vieillot.

Ramphocænus^[1] Vieillot, Nouv. Dict. d'Hist. Nat., xxiv, 1818, 112 (diagnosis but no type given). Ramphocænus Vieillot, Nouv. Dict. d'Hist. Nat., xxix, 1819, 5. (Type, R. melanurus Vieillot.)

Rhamphocænus (emendation) Strickland, Ann. Mag. N. H., vi, 1841, 421.

Acontistes Sundevall, Kgl. Vet.-Ak. Handl., 1835 (1836), 95. (Type, Ramphocænus melanurus Vieillot.)

Scolopacinus Bonaparte, Proc. Zool. Soc. Lond., 1837, 119. (Type, S. rufiventris Bonaparte.)

Very small Formicariidæ (length about 120-135 mm.) with дong,

slender bill (longer than head), long, slender tarsi (nearly as long as exposed culmen) and with tail four-fifths as long as wing.

Bill very long (longer than head), straight, and slender, its width at frontal antiæ decidedly greater than its depth at same point and equal to about one-fourth the distance from nostril to tip of maxilla; culmen sharply ridged, straight, the extreme end abruptly and rather strongly decurved, the tip of maxilla very minutely uncinate; maxillary tomium faintly concave for anterior half or more, very faintly (obsoletely) notched subterminally; mandibular tomium straight, faintly decurved terminally, without trace of subterminal notch, the tip of mandible very slightly decurved; gonys nearly straight, very slightly prominent basally. Nostril exposed, widely separated from feathering of latero-frontal antiæ, narrow, longitudinal, overhung by a broad, convex operculum. Rictal bristles distinct, but rather few and slender; feathers of chin without terminal setæ. Wing moderate or relatively rather large, with longest primaries extending slightly but decidedly beyond secondaries; fifth, sixth, and seventh primaries longest, the tenth (outermost) less than half as long as longest, the ninth much shorter than secondaries. Tail about four- fifths as long as wing, graduated (graduation less than distance from nostril to tip of maxilla), the rectrices (10) rather narrow, rounded terminally. Tarsus about as long as bill from frontal antiæ, two- fifths as long as wing, slender, the scutella of acrotarsium fairly distinct, those of the planta tarsi undivided; middle toe, with claw, about two-thirds as long as tarsus; outer toe, without claw, reaching to beyond middle of subterminal phalanx of middle toe, the inner toe decidedly shorter; hallux about as long as inner toe but much stouter; basal phalanx of middle toe wholly united to both outer and inner toes, the second phalanx partly united to outer toe; claws moderate in size and curvature, that of the hallux shorter than its digit. Plumage full, soft, and blended, that of rump and flanks elongated, more lax or fluffy; feathers of pileum not elongated.

Coloration. — Above plain brownish (back, etc., sometimes more grayish), the tail blackish, with or without whitish tip to rectrices; beneath whitish, more or less strongly buffy or rufescent laterally: sexes alike.

Range. — Guatemala to southeastern Brazil. (Four species.)

RAMPHOCÆNUS RUFIVENTRIS RUFIVENTRIS (Bonaparte).

NORTHERN LONG-BILLED ANTWREN.

Adults {sexes alike). — Pileum and hindneck plain olive-brown (between prouts brown and raw umber); rest of upper parts (except tail) plain deep grayish olive or olive-slaty, the concealed portion of wing-feathers darker; tail dull slate-black or blackish slate, the three outer rectrices (on each side) with an apical or subapical area of dull white, this most developed on inner web of two outermost, which have a narrow longitudinal area of dusky on terminal or subterminal portion of outer web; sides of head and neck plain cinnamon or russet, broken by an indistinct postocular streak of olive-brownish; chin and throat white, more or less broken by partly exposed dusky basal portion of feathers; rest of under parts plain buff, or pinkish buff, deepest (sometimes nearly ochraceous-buff) laterally, paler medially (sometimes nearly white on abdomen); thighs mostly dusky olive-gray; under wing-coverts pale cream buff or buffy white; inner webs of remiges edged with white or buffy white; maxilla horn brown (sometimes darker terminally), mandible much paler (pale bluish gray to flesh color in life); iris brown; legs and feet horn color (bluish gray or grayish blue in life).

Adult male. — Length (skins), 109-127 (120); wing, 46-54.5 (51.2); tail, 36.5-43.5 (40.9); culmen, 22-26 (24); tarsus, 20-21.5 (20.9); middle toe, 10.5-12 (11.1).^[2]

Adult female. — Length (skins), 105-119 (113); wing, 45.5-53 (49.2); tail, 36-41 (38.6); culmen, 20-24.5 (23.1); tarsus, 20-22 (21.3); middle toe, 11-11.5 (11.2).^[3] </ref>

Young. — Essentially like adults, but back, rump, etc., soft grayish brown (nearly concolor with pileum and hindneck), and under parts pale grayish brown, approaching dull buffy whitish on throat and abdomen.

Southeastern Mexico, in States of Vera Cruz (Playa Vicente; Buena Vista; San Andrés Tuxtla), Oaxaca (mountains near Santo Domingo), and Chiapas (Palenqiio; San Benito) and southward through Guatemala (Cobán; Choctúm; Chiséc; Lanquín; Retalhuleu; Los Amates, Yzabál), British Honduras (Orange Walk; Cayo; near Soldiers Creek; near Manatee Lagoon), Honduras (Truxillo), Salvador (La Libertád; Volcan de San Miguél), Nicaragua (Chinandega; Greytown; Los Sábalos; Sucuyá; Rio Escondido), and Costa Rica (Orosí; Lagarto; Bebedero; Miravalles; Pozo Azúl de Pirrís; Pozo de Térraba; Pozo del Pitál; Pozo del Rio Grande; Paso Reál; Boruca; El Hogár; Carrillo; Guácimo; Cuábre; Laguaria; Santa Maria de Dota; Tenório; El Generál ; Bolsón) to Panamá (Santa Fé de Verágua; Calobre; Bugaba; Lion Hill; Panamá; Sabana de Panamá).

Scolopacinus rufiventris Bonaparte, Proc. Zool. Soc. Lond., 1837, 119 (Guatemala; coll. Velasquez).

R[hamphocænus] rufiventris Gray and Mitchell, Gen. Birds, i, March, 1847, 157, pl. 47, fig. 2.

Rhamphocænus rufiventris Sclater, Proc. Zool. Soc. Lond., 1857, 202 (San Andrés Tuxtla, Vera Cruz); 1858, 244 (monogr.); Cat. Am. Birds, 1862, 184 (Choctúm, Guatemala); Ibis, 1883, 95, part (Guatemala to Panamá; descr.; crit.); Cat. Birds Brit. Mus., xv, 1890, 261, part (Cobán, Choctúm, Chiséc, Lanquín, and Retalhuleu, Guatemala; Bebedero, Costa Rica; Bugaba, Calobre, and Santa Fé de Verágua, Panamá). — Sclater and Salvin, Proc. Zool. Soc. Lond., 1864, 356 (Panamá; crit.). — Nutting, Proc. U. S. Nat. Mus., vi, 1883, 386 (Sucuyá, Nicaragua), 405 (Los Sábalos, Nicaragua). — Ridgway, Proc. U. S. Nat. Mus., X, 1888, 581 (Truxillo, Honduras). — Salvin and Godman, Biol. Centr.-Am., Aves, ii, 1892, 219, part (San Andrés Tuxtla and Playa Vicente, Vera Cruz; Orange Walk, Brit. Honduras; Choctúm, Chiséc, Lanquín, and Retalhuleu, Guatemala; Truxillo, Honduras; La Libertád and Volcan de San Miguél, Salvador; Chinandega, Sucuyá, Los Sábalos, and Greytown, Nicaragua; Bebedero, Costa Rica; Bugaba, Santa Fé de Verágua, Calobre, and Lion Hill, Panamá). — Thayer and Bangs, Bull. Mus. Comp. Zool., xlvi, 1906, 217 (Sabana de Panamá). — Dearborn, Pub. 125, Field Mus. Nat. Hist., 1907, 109 (Los Amates, Guatemala). — Carriker, Ann. Carnegie Mus., vi, 1910, 611 (Costa Rica; habits).

[Rhamphocænus] rufiventris Sharpe, Hand-list, iii, 1901, 27, part (s. Mexico to Panamá).

[Rhamphocænus] rufiventer Heine and Reichenow, Nomencl. Mus. Hein. Orn., 1890, 126, part (Cobán, Guatemala).

Ramphocænus rufiventris Sclater, Proc. Zool. Soc. Lond., 1859, 383 (Playa Vicente, Vera Cruz; crit.). — Salvin and Sclater, Ibis, 1860, 399 (Choctúm and Lanquín, Guatemala). — Lawrence, Ann. Lyc. N. Y., viii, 1863, 484 (Lion Hill, Panamá); viii, 1865, 182 (Greytown, Nicaragua). — Salvin, Proc. Zool. Soc. Lond., 1867, 145 (Santa Fé de Verágua, Panamá); 1870, 195 (Calobre and Bugaba, Panamá); Ibis, 1869, 319 (Bebedero de Nicoya, Costa Rica). — Boucard, Ann. Soc. Linn. Lyon, 1878, 39 (Guatemala). — Richmond, Proc. U. S. Nat. Mus., xvi, 1893, 501 (Greytown and Rio Escondido, Nicaragua; habits). — Underwood, Ibis, 1896, 440 (Volcan de Miravalles, Costa Rica). — Lantz, Trans. Kansas Acad. Sci. for 1896-97 (1899), 221 (Cayo, Brit. Honduras).

[Ramphocaenus] rufiventris Bonaparte, Consp. Av., i, 1850, 201.

[Ramphocænus] rufiventris Sclater and Salvin, Nom. Av. Neotr., 1873, 73.

Rhamphocenus rufiventris Cherrie, Anal. Inst. Fis.-Geog. Costa Rica, vi, 1893, 19 (Pozo del Pitál, Costa Rica).

Genus MICROBATES Sclater and Salvin.

Microbates^[4] Sclater and Salvin, Nom. Av. Neotr., 1873, 155. (Type, M. torquatus Sclater and Salvin = Rhamphocænus collaris Pelzeln.)

Very small, long-billed, long-legged Formicariidæ, similar in appearance to Rhamphocænus but with shorter and broader bill, longer tarsi, relatively longer toes (especially the hallux), narrower nostrils with differently shaped operculum, and much shorter tail (only about half, instead of four-fifths) as long as wing.

Bill about as long as head, nearly straight, its width at latero- frontal antiæ much greater than its depth at same point and equal to much more than one-third the distance from nostril to tip of maxilla; culmen sharply ridged, straight for basal half (more or less), then very gradually decurved until near end, where more strongly decurved, the tip of maxilla minutely but distinctly uncinate; maxillary tomium faintly concave, minutely notched subterminally; mandibular tomium very faintly convex, at least terminally, without trace of subterminal notch; gonys faintly convex basally, straight terminally. Nostril exposed, distinctly separated from feathering of latero-frontal antiæ, narrow, longitudinal (slit-like), overhung by a broad but not convex membraneous operculum. Rictal bristles distinct but rather few and slender; feathers of chin without terminal setæ. Wing rather large, with longest primaries extending slightly beyond secondaries, much rounded; fifth and sixth primaries longest, the tenth (outermost) less than half as long as the longest, the ninth very much shorter than, the eighth about equal to, secondaries. Tail slightly more than half as long as wing, rounded (graduation equal to much less than half the distance from nostril to tip of maxilla), the rectrices (10) rounded at tip. Tarsus very long (decidedly longer than whole culmen, nearly half as long as wing), slender, the acrotarsium faintly scutellate, the planta tarsi completely fused; middle toe, with claw, decidedly shorter than tarsus (equal to or slightly longer than exposed culmen); outer toe, with claw, reaching to about middle of subterminal phalanx of middle toe, the inner toe decidedly shorter; hallux much longer than inner toe (about as long as outer toe), much stouter; basal phalanx of middle toe wholly united to both lateral toes; claws moderate in size and curvature, that of the hallux much shorter than its digit. Plumage full, soft, and blended, that of rump and flanks elongated, more lax or fluffy; feathers of pileum not elongated.

Coloration. — Above plain brown; sides of head blackish and white, or tawny; beneath white passing into dusky on flanks and under tail- coverts, the chest crossed by a band of black (M. collaris) or under parts of body gray, chest streaked with black and white, and throat white bordered on each side by a black stripe; sexes alike.

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1. ?, rostrum, ?, novus. (Vieillot.)
2. Eighteen specimens.
3. Sixteen specimens.

   Locality.	Wing.	Tail.	Culmen.	Tarsus.	Middle toe.
   males.
   Two adult males from southern Mexico	50	40	22	21.2	10.7
   Two adult males from Chiapas and Guatemala	50.7	43	24.5	20.7	11.2
   One adult male from Honduras	54	40	26	21	11
   One adult male from British Honduras	46	42	24	21	10.5
   Ten adult males from Nicaragua (4) and Costa Rica (6)	51.7	41	24	20.9	11.3
   Two adult males from Panamá (line of railway)	51.5	39.2	23.2	20.7	10.7
   Four adult males (R. r. sanctæ-martæ) from Colombia	51.6	39.2	23.2	20.7	10.7
   females.
   Two adult females from southern Mexico (Vera Cruz).	48.2	39.2	24	21	11
   One adult female from Chiapas	49	37.5	23	22	11.5
   Two adult females from British Honduras	47.5	39.5	22.5	21	11
   Ten adult females from Nicaragua (3) and Costa Rica (7)	49.4	38.4	23.1	20.8	11.2
   One adult female from Panamá (Verágua)	51.5	39	-	22	11
   One adult female (R. r. sanctæ-martæ) from Colombia	47	38	24.5	22	12

4. ?, parvus et ?, qui incedit." (Sclater and Salvin.)