Cosmocephalus capellae Yamaguti, 1935

Mutafchiev, Yasen, Halajian, Ali & Georgiev, Boyko B., 2010, Two new nematode species of the genus Cosmocephalus Molin, 1858 (Spirurida: Acuariidae), with an amended generic diagnosis and an identification key to Cosmocephalus spp., Zootaxa 2349, pp. 1-20 : 15

Cosmocephalus capellae Yamaguti, 1935

Material studied: One male specimen, CLGE-BAS N000.461; host: Tringa totanus L. ( Charadriiformes , Scolopacidae ); collected from Durankulak Lake, Bulgarian Black Sea coast (2 April 1986); site of infection: oesophagus.

Description ( Fig. 8A–D )

Body length 5.5 mm. Maximum body width 179, about mid-body; width 86 at level of cloaca. Tail 220 long. Anterior end with two triangular pseudolabia, each bearing single amphid and pair of prominent papillae. Pair of swellings situated dorsally and ventrally at bases of pseudolabia ( Fig. 8 А). Cordons arise dorsally and ventrally between pseudolabia, extending in longitudinal direction to 241 from anterior body end, recurrent and anastomosing laterally at 74 from anterior body end ( Fig. 8 А). Cordons with slightlyexpressed scalloped appearance of descending arm; maximum width of cordons 11 µm; cuticular plates delicate (each c. 1 µm long); cuticular ridge passing along outer rim of cuticular plates. Deep, almost closed longitudinal groove situated between plates and cuticular ridge. Deirids 12 long, at 270 from anterior body end, tricuspid. Excretory pore at 351 from anterior body end. Left postdeirid and right postdeirid at 3.3 mm and 3.5 mm, respectively, from anterior body end. Lateral alae well-developed, extending from level posterior of deirids to level about middle of body, 18 wide. Buccal cavity 237 long and 11 wide. Muscular oesophagus 451 long and 38 wide. Glandular oesophagus 2,418 long and 90 wide. Nerve ring at 261 from anterior body end. Cuticle 7 thick. Distance between cuticular striations 2–3 μm. Caudal alae 354 long. Single ventral cuticular ridge extending between level at 1,158 from posterior body end to caudal alae. Single median sessile precloacal papilla present. Nine pairs of pedunculate caudal papillae, 4 precloacal and 5 postcloacal ( Fig. 8B ). Anterior four pairs of postcloacal papillae with almost equal distance between them; fifth pair situated in posterior part of tail. Sixth pair of postcloacal papillae sessile, smaller, situated between bases of last pedunculate papillae. Left spicule 389 long, 12 wide, with prominent projection on its distal end ( Fig. 8D ). Right spicule 138 long, 28 wide ( Fig. 8C ). Phasmids subterminal. I CL/BL 0.044; I mOE/gOE 0.187; I OE/BL 0.519; I CA/BL 0.064; I LSP/RSP 2.819.

Remarks. Cosmocephalus capellae has been reported as a parasite of Scolopacidae , Charadriidae (Charadriiformes) and Anatidae (Anseriformes) from Europe ( Iceland, Ukraine), Asia ( Armenia, Uzbekistan, Kirghizia, Western Siberia, Japan) and North America ( USA, Canada) (data summarised from Threlfall 1970; Smogorzhevskaya 1990; Wong & Anderson 1993). According to Smogorzhevskaya (1990), C. capellae has to be regarded as a specific parasite of Charadriidae and Scolopacidae ; she believed that the two records of this species from ducks ( Anas querquedula L. and A. clypeata L.) were accidental.

The nematode described by von Linstow (1877) as Cosmocephalus obvelatus (= Filaria obvelata ) from Tringa erythropus (Pallas) (= Totanus fuscus) morphologically corresponds with C. capellae . Smogorzhevskaya (1990) presented a detailed description of C. capellae ; however, there is a difference between the length of the left spicule as given in the text (710 µm) and the length as shown in the relevant illustration (about 420 µm).

The specimen from Bulgaria corresponds to the original description ( Yamaguti 1935) (see Table 1). This is the first record of C. capellae from Bulgaria.

Figures

FIGURE 8 A – D. Cosmocephalus capellae, male. A. Anterior end, lateral view; B. Posterior end, lateral view; C. Right spicule, dextral view; D. Left spicule, sinistral view. Scale bars: A – D = 100 μm.