442
and brasilianum group (S America, e. of Andes; Ferruginous Pygmy Owl) may best be treated as separate
species.
BARN OWL Tyto alba (p. 150). The Barn Owl Tyto alba complex comprises 3 genetic lineages that are
treated differently by different authors. American Barn Owl T. [a.] furcata is treated as a species by IOC,
but critical biological analysis of the situation could help resolve this issue.
SOUTHERN BAND-TAILED PIGEON Patagioenas [fasciata] albilinea (p. 164). Differences in plumage
and voice indicate a clear species break in Middle America between the fasciata group (N America to
Nicaragua; Northern Band-tailed Pigeon) and albilinea group (Costa Rica to S America).
VERREAUX’S [WHITE-TIPPED] DOVE Leptotila [verreauxi] verreauxi (p. 168). Differences in song
and bare-part coloration suggest that the fulviventris group (Mexico to w. Nicaragua; Lawrence’s Dove)
and verreauxi group (Nicaragua to S America) represent separate species; critical study of the potential
sympatry in Nicaragua could be informative.
COMMON SQUIRREL CUCKOO Piaya [cayana] cayana (p. 174). Differences in plumage and voice
indicate that the mexicana group (w. Mexico; Mexican Squirrel Cuckoo) and widespread cayana group
(e. Mexico to S America) are best treated as separate species; the latter group may include further cryptic
species in S America.
AZTEC [OLIVE-THROATED] PARAKEET Eupsittula [nana] astec (p. 176). Differences in morphology,
plumage, bare parts, and voice indicate that the astec group (Mexico to w. Panama) and nana group
(Jamaica; Jamaican Parakeet) are best treated as separate species; also see Latta et al. (2012).
VERAGUAS [BROWN-THROATED] PARAKEET Eupsittula [pertinax] ocularis (p. 176). Differences in
plumage, bare parts, and voice indicate that the ocularis group (Costa Rica to Panama) is best treated as
a species distinct from S American and Caribbean taxa in the Brown-throated Parakeet complex, which
may comprise further cryptic species. We favor Veraguas (rather than Veraguan) as a species epithet, as
typically done for birds named for geographic entities below (and even at) country level.
NORTHERN BLACK-THROATED TROGON (p. 184). Differences in voice, morphology, and plumage
(supported by molecular data) indicate that northern tenellus group (Honduras to nw. Colombia) is best
treated as specifically distinct from populations in S America (Dickens et al. 2021.
ELEGANT TROGON Trogon [elegans] elegans (p. 186). Differences in plumage and voice indicate that
the ambiguus group (Mexico and sw. US; Coppery-tailed Trogon) and elegans group (Guatemala to Costa
Rica) are best treated as separate species.
NORTHERN COLLARED TROGON Trogon [collaris] puella (p. 186). Differences in plumage and song
indicate that the puella group (Mexico to Panama) and collaris group (e. Panama to S America) are best
treated as separate species.
TROPICAL RINGED KINGFISHER Megaceryle [torquata] torquata (p. 190). Differences in
morphology, plumage, ecology, and voice indicate that the torquata group (Mexico to tropical S
America) and stellata group (s. Chile and adjacent Argentina; Austral Ringed Kingfisher) are best treated
as separate species.
LESSER PIED PUFFBIRD Notharchus [tectus] subtectus (p. 196). Differences in morphology, plumage,
and voice indicate that the subtectus group (Central America to nw. S America) and tectus group (S
America, e. of Andes; Greater Pied Puffbird) are best treated as separate species.
AZURE-HOODED JAY Cyanolyca cucullata (p. 210). Differences in plumage and voice suggest that the
mitrata group (Mexico to Honduras; Northern Azure-hooded Jay) and cucullata group (Costa Rica and
w. Panama; Southern Azure-hooded Jay) represent separate species.
GRAY-TAILED (WHITE-THROATED) [VARIABLE] MOUNTAIN-GEM Lampornis [castaneoventris]
cinereicauda and PURPLE-THROATED [VARIABLE] MOUNTAIN-GEM Lampornis [castaneoventris]
calolaemus (p. 220). Taxonomy of the appropriately named Variable Mountain-gem Lampornis casta
neoventris complex remains unresolved, with 6 taxa involved, one of them formally undescribed (Miller
& Rosas, unpubl. data). The main differences are in male gorget and tail color. One option is to lump all
taxa into a single variable species; another is to treat various taxa as distinct, which we do here for the 2
main types occurring in Costa Rica, as also done provisionally by Stiles & Skutch (1989).