Description

Description (Fig. 3) Based on 2 male specimens. Males. Trunk elongate, almost cylindrical but tapering both anteriorly and posteriorly, 3.7 - 4.0 long, 0.9 - 1.1 wide. Numerous amoeba-shaped hypodermal nuclei. Proboscis cylindrical (in both specimens invaginated to different degrees, i. e. anterior third in first specimen and anterior two-thirds in other), c. 0.93 - 0.95 long, 0.23 wide. Proboscis armament consists of 18 longitudinal rows of 12 - 13 hooks (anterior hooks invaginated) (in 1 specimen). Most of hooks with posteriorly directed roots; only pos- teriormost 4 (3) hooks spiniform with short apophyses. Length of first 8 (9) hooks – blade 52 - 59 µm, root 29 - 49 µm; length of last 4 (3) spiniform hooks – 42 - 52 (54) µm, root 12 - 22 µm. Neck short, c. 0.13 long, 0.25 wide. Proboscis receptacle doublewalled, 1.5 long, 0.26 wide. Lemnisci band-shaped, c. 1.5 long, c. 0.05 wide (only 1 measured). Testes spherical, 0.26 - 0.32 long, 0.23 - 0.35 wide, situated in tandem in middle of trunk, at c. 0.06 from one another; anterior testis 0.14 from tip of proboscis receptacle. Cement glands 6 in number, tubular, arranged in 2 groups of 3; longest cement gland of first group (1.70 long) present immediately posterior to anterior testis; remaining 2 cement glands slightly further posterior, 1.44 and 1.01 long; 2 of cement glands of second group present posterior to hind testis, 1.35 long, with remaining cement gland slightly further posterior, 1.03 long. Genital bursa (everted in 1 specimen) 0.55 long, 0.45 wide.

Common Names

Taxonomic Hierarchy

Kingdom: Animalia

Phylum: Acanthocephala

Class: Palaeacanthocephala

Order: Polymorphida

Family: Plagiorhynchidae

Genus: Plagiorhynchus

Species: Plagiorhynchus charadrii (Yamaguti, 1939)