Centrorhynchus chabaudi Golvan, 1958

Smales, Lesley R., 2011, Centrorhynchidae (Acanthocephala) including the description of new species of Centrorhynchus from birds from the Côte d’Ivoire, Africa., Revue suisse de Zoologie 118 (2), pp. 307-318 : 309-311

Centrorhynchus chabaudi Golvan, 1958

Figs 1-4

MATERIAL EXAMINED: One male, one immature female from Accipiter badius Gmelin, 1788 , small intestine; Côte d’Ivoire, Lamto, 12.02.1987, J. Mariaux ( MNHG INVE 38488 ) .

DESCRIPTION

General: Trunk spineless, elongate, sub cylindrical, dilated anteriorly in region of lemnisci and proboscis receptacle. Proboscis in 2 parts, widest anterior to constriction, constriction at insertion of proboscis receptacle about 55-63% of distance from apex to proboscis base. Proboscis armed with 30-34 rows 15-22 hooks and spines. Anterior 4-5 hooks with large simple roots, next 5-6 hooks transitional with short roots with luniform- cresentic manubria, next 6-11 hooks spiniform, inserted on posterior part of proboscis, the more anterior of these with small, roughly triangular shaped roots. Neck spineless, well defined, shorter than broad. Proboscis receptacle double walled. Lemnisci tubular, inserted at base of neck, extend posteriorly beyond proboscis receptacle. Cerebral ganglion located at mid region of proboscis receptacle, just posterior to neck. Principal canals of lacunar system lateral, connected by transverse anastomoses.

Male: based on one specimen. Trunk 22 mm long, 1200 at widest part. Proboscis total length 884, greatest width 340, just anterior to constriction; posterior part 374 long. Hooks I-V thorns 55-80 long, hooks V-XI thorns 40-50 long, spines X-XXII 20-40 long. Neck 150 long, 374 wide at base. Proboscis receptacle 2250 long, 350 wide; lemnisci 2900 long. Testes oval, tandem, not contiguous, 0.5mm apart; anterior testis, 3.06 mm from anterior end of trunk, 935 long, 425 wide; posterior testis 1020 long, 408 wide. Cement glands elongate, tubular, begin immediately posterior to posterior testis, 11.4 mm long; number not determined; cement ducts elongated, 2805 long; Saefftigen’s pouch and retracted bursa 2210 long; entire male system occupying about 86% trunk length.

Female: based on 1 immature female. Trunk 15 mm long, dilated anterior portion 3060 long, 510 wide, main trunk 255 wide. Proboscis partially inverted about 910 long, greatest width 400, just anterior to constriction; posterior part 370 long. Hooks V-VII 30-40 long, spines 20-26. Neck 135 long by 400 wide. Proboscis receptacle 1020 long, 205 wide; lemnisci 3400 long. Genital apparatus not observed, no mature eggs seen. Genital pore sub terminal.

COMMENTS: Centrorhynchus chabaudi was described by Golvan (1958) from two female worms up to 48mm long, main trunk 1000 wide, with a proboscis armature of 30-34 longitudinal rows of 15-16 hooks. The proboscis was 1350 long and 650 wide just anterior to the constriction and 700 wide at the base, with the neck 850 long by 450 wide. Hooks I-V thorns 55-96 long, hooks VI-X thorns 57-67 long, spines XVI 36 long. Neck 450 long, 850 wide at base. The proboscis receptacle was 2200 long by 400 wide and the lemnisci about 2000 long. Golvan (1958) also described the female genital apparatus (uterine bell to genital pore, 2000 long, genital pore sub terminal, at base of distinct terminal digitiform process) and eggs (oval, external shell thickened, sculptured with longitudinal ridges and grooves, 60 long, 23 wide).

The type host Gyps africanus (Salvadore, 1865) was given as Pseudogyps africanus , the white backed vulture, collected from Nioro du Sahel in ‘ the Sudan.’ This locality is a town in the Kayes Region of the Republic of Mali bordering on the Côte d’Ivoire to the south. There have been no further records of C. chabaudi since then.

The two specimens, both the male and the immature female, from A. badius from Lamto in the Côte d’Ivoire conformed to the description given by Golvan (1958) as to general body shape and the proportions of the proboscis and lemnisci and in particular to the proportions and shapes of the proboscis hooks and spines. The proboscis armature varied only in the number of spines in each row. The number of spines on the specimens examined by Golvan (1958) is not clear. He describes the proboscis armature as having a total of 15 or 16 hooks, which would give 6- 7 spines per row. In his figure 4, however, a total of 17 hooks is shown. This would suggest 6-8 spines for the specimens from Nioro du Sahel compared with the 10-11 spines for the specimens from Lamto. This variation in number of spines can be accommodated as either individual variation (only four worms having been examined in total) or perhaps host induced variation. The finding of a male specimen of C. chabaudi has enabled the preparation of a more complete description of the species. The number of cement glands, however, three or four, could not be determined from the whole mount of the male and there was no other specimen that could be dissected to confirm the number.