Details are given of four species new to the avifauna of the Central African Republic, based on specimens overlooked in American museum collections and previously unpublished: Madagascar Cuckoo Cuculus rochii, Black-necked Wattle-eye Dyaphorophyia chalybea, White-browed Scrub Robin Cercotrichas leucophrys and Grey Ground Thrush Geokichla princei.
We present here details of some museum specimens that represent additions to the avifauna of Central African Republic, but which have not appeared in the literature. A list of the species documented for this and other Afrotropical countries is, or will be, presented at: https://www.africanbirdclub.org/dowsett-checklists. In the case of the Central African Republic's avifauna there are numerous unpublished species records that would be new, and work is in progress to document them. Meanwhile, details of these are obtainable from the first author.
MADAGASCAR CUCKOO Cuculus rochii
Friedmann (1978) reported five specimens of Dusky Long-tailed Cuckoo Cercococcyx mechowi collected by A. Williams on 1–17 June 1976, near the Ouossi River, c.11 km west of Baroua, Mbomou Prefecture (c.05°20′N, 24°20′E), housed in the Los Angeles County Museum. However, examination shows that one of them, collected on 12 June (LACM 84699), labelled as a female with ovary not enlarged, stands apart from the other correctly identified C. mechowi (Fig. 1). It had been shot ‘40 feet up in [a] mature forest tree’ (specimen label) within an extensive forest where the river had cut into a partially grassy plateau (A. Williams in litt. 2019). Its small size, proportions (wing: tail ratio) and plumage pattern indicate it is not a Dusky Long-tailed Cuckoo.
The largely grey throat (with a few dark-barred feathers), folded wings extending far towards the tip of the tail and basic measurements (wing 158 mm, tail 139 mm) suggest that it is attributable to either Asian Lesser Cuckoo Cuculus poliocephalus or Madagascar Cuckoo C. rochii. These two species are very similar (being often treated as conspecific in the past) and have long caused confusion both in the field and museum. Several criteria were proposed by Becking (1988) for separating specimens of the two species, specifically wing and tail measurements, body mass, carpometacarpal feather patterning and the form of the mandibular symphysis.
Using Becking's (1988) criteria, the LACM 84699 cuckoo shows barred carpometacarpal feathering, a rounded mandibular symphysis, heavy mass (61 g) and large measurements (wing, tail), which attributes indicate it to be C. rochii. The June collection date is also more consistent with C. rochii given these species' known migratory movements—C. rochii visiting mainland Africa between May and September (Becking 1988, Payne 2005), with some remaining during the austral summer (Ginn 1999, Spottiswoode & Allan 2000, Dowsett-Lemaire & Dowsett 2006), while C. poliocephalus visits Africa exclusively between November and early May (Becking 1988, Payne 2005).
LACM 84699 is a juvenile beginning the transitional moult to adulthood. The few barred feathers on the throat are interpreted to be remnants of the completely barred throat found in juveniles. The remiges and rectrices are old and heavily worn, indicating that moult was not far advanced at the time it was collected.
Fig. 2 maps East African records of C. rochii, wherein it can be seen that the Baroua record is c.300 km north-west of the nearest, Avakubi, Democratic Republic of Congo (01°22′N, 27°35′E: Chapin 1939).
BLACK-NECKED WATTLE-EYE Dyaphorophyia chalybea
A female was collected on 24 May 2001 by D. Willard in the Ndoki sector of Dzanga-Ndoki National Park, 38.6 km south of Lidjombo (02°21′N, 16°03′E). It is in the Field Museum of Natural History, Chicago (FMNH 429637: VertNet.org). This record represents just a slight extension to the east from Lobéké, Cameroon (02°09′N, 15°44′E: Dowsett-Lemaire & Dowsett 2000).
WHITE-BROWED SCRUB ROBIN Cercotrichas leucophrys
Examination of a scrub robin specimen in the American Museum of Natural History, New York, collected on 27 June 1998, c.8 km south of Beya (i.e. near Monasao) by A. L. Porzecanski (AMNH 832113), confirms its identification as C. leucophrys munda. The bird was collected in a small savannah at 03°17′N, 16°14′E (P. Sweet in litt. 2018), and there are populations of C. l. munda in enclosed savannahs in several parts of the northern forests, the nearest being to the east, at Gele, Bosobolo (04°48′N, 19°02′E: Schouteden 1962). This specimen is heavily worn, but characters that distinguish it from the forest-dwelling Brown-backed Scrub Robin C. hartlaubi include (1) the well-defined streaking on the breast (not diffuse), (2) the large pale yellowish base to the mandible (largely all black in hartlaubi) and (3) the warm cinnamon mantle (not drab grey-brown as in hartlaubi). Fig. 3 compares AMNH 832113 to skins of C. leucophrys and C. hartlaubi from the Congo (collected by J. P. Chapin).
GREY GROUND THRUSH Geokichla princei
A female was collected in forest at Bayanga (02°54′N, 16°15′E) on 23 June 1998 by P. Beresford (AMNH 832142; Fig. 4). There have been several observations in the area (R. Cassidy in litt. 2019). This is an easterly extension of the known range from Bitye, Cameroon (03°10′N, 12°20′E: Good 1953) and M'Passa, Gabon (00°30′N, 12°50′E: Brosset & Erard 1986).
We are grateful to Paul Sweet and Tom Trombone for access to information concerning specimens in AMNH, and to Kimball Garrett and Allison Shultz for access to specimens in Los Angeles (LACM). Nik Borrow is thanked for comments on some points of identification. Andrew Williams kindly provided details concerning the 1976 Lathrop expedition to the Central African Republic. For useful comments on the submitted manuscript we thank Rod Cassidy, Ron Demey and Guy Kirwan.