Centrorhynchus halcyonicola, R. & Smales, 2011

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 : 314-316

Centrorhynchus halcyonicola sp. n.

Figs 14-17

MATERIAL EXAMINED: Holotype male from Halcyon malimbica (Shaw, 1811) small intestine; Côte d’Ivoire, Korhogo, 27.01.1987, J. Mariaux ( MNHG INVE 38485 ). – 1 male, proboscis missing and 1 piece male from H. malimbica small intestine; Côte d’Ivoire, Lamto, 13.02.1987, J. Mariaux ( MNHG INVE 38490 ). Prevalence: 40 %.

DESCRIPTION

General: Trunk, spineless, elongate, cylindrical. Proboscis in 2 parts with constriction at insertion of proboscis receptacle about half way between apex and proboscis base, anterior part sub cylindrical. Proboscis armed with 38-40 rows 14-17 hooks. Anterior 2-3 hooks with large simple roots, thorns 40-40.5 long; next 2-3 hooks transitional, having laterally directed manubria, thorns 25- 30 long; next 2 hooks transitional with anteriorly directed manubria, thorns 40 long; 8-9 spiniform hooks inserted on posterior part of proboscis posterior to constriction, thorns 20-40 long. Neck spineless, not well defined. 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. Principal canals of lacunar system lateral, connected by transverse anastomoses.

Male: measurements taken from holotype. Trunk 20 mm long, 400 at widest part. Proboscis total length 640, greatest width 335; posterior part 335 long 268 wide. Proboscis receptacle 1370 long 205 wide; lemnisci 1530 long. Testes oval, tandem, close together, not contiguous 150 apart; anterior testis, 1.8 mm from anterior end of trunk, 440 long, 340 wide; posterior testis 510 long, 290 wide. Cement glands, 3, elongate, tubular, begin posterior to posterior testis, 14 mm long; cement ducts elongated, 1955 long; Saefftigen’s pouch and infolded bursa 1105 long; entire male system occupying about 85% trunk length.

COMMENTS: Although only male specimens were available for examination they were sufficiently distinctive to allow differentiation from all other species of Centrorhynchus . Despite the proboscis being slightly inverted in the only intact specimen the total length and hook formula could be calculated by observing the clearly visible inverted portion of the proboscis. Centrorhynchus halcyonicola sp. n. with a proboscis armature of 38-40 rows of 14-17 hooks falls within the same group as C. mariauxi as discussed above. Within that group C. halcyonicola is closest to C. mariauxi which has 34-36 rows of 15-20 hooks, 2-4 of which are hooks with large simple roots. The shapes of the roots of the transitional hooks of C. halcyonicola , however differ from those of C. mariauxi (figs 7, 15), the thorns of the anterior hooks are longer in C. halcyonicola , 40-40.5 compared with 20-25.5 and there are fewer spines. Centroryhnchus halcyonicola further differs from C. mariauxi in the size of the testes, larger in C. halcyonicola , and the proportions of the male system, the testes being placed more anteriorly and closer together in C. halcyonicola .

Similarly C. halcyonicola differs from all other species known from Africa as discussed above for C. mariauxi .

The proboscis hook morphology of C. halcyonicola is similar to that described for C. alcuonis (Müller, 1780) from Asio atus, Linneaus, 1758, the long eared owl and Strix aluco Linneaus, 1758, the tawny owl from Hungary by Dimitrova et al. (1995), particularly in regard to the shapes of the roots of the anterior and transitional hooks. The armature differs, however, in the number of rows of hooks, 38-40 compared with 28 and C. alcuonis further differs in the size of the proboscis receptacle, 1370 compared with 1450-1800 and the proportions of the male system ( Dimitrova et al., 1995). Both owl species also occur in North Africa supporting the possibility that there could be a link between the two species of Centrorhynchus .