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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Dentomermis

Dentomermis Robtsov & Polishchuk, 1975 (ref. ID; 7870 original paper)

Family Mermithidae (ref. ID; 7870)

ref. ID; 7870

Body thin, long, in males a=200 or more. Cuticle thin with no visible fibration. Six head papillae. Mouth terminal, stoma narrow. Pointed odontostyle in the oral cavity (in the anterior and slightly widened portion of the gullet). Small amphids, pore-like. Six longitudinal notochords, narrow lateral notochords. Two spicules fused near tha apex, musculature of the copulative apparatus simple; protractors from the bursal and muscle fibers along the canal of spicules. Genital papillae in 3 rows, numerous. Tail moderately pointed. It is similar in overall characters to the genus Mesomermis Daday, 1913, which has comparatively large round amphids, no odontostyle, wider and more strongly developed longitudinal notochords, a more complex musculature of the copulative apparatus, and a short body. (ref. ID; 7870)

Type species

Dentomermis markevitschi (ref. ID; 7870)
  1. Dentomermis markevitschi Robtsov & Polishchuk, 1975 (ref. ID; 7870 original paper)

Dentomermis markevitschi Robtsov & Polishchuk, 1975 (ref. ID; 7870 original paper)

Descriptions

Body thin, long. Head capsule bluntly rounded and wider than the body. Body diameter at the level of the head papillae 40, at the nerve ring 60, in the middle of the body 108, at the posterior end of the trophsome 80, with the ratio of these quantities 1:1, 5:2, 7:2, 0. Nerve ring at a distance of 260. Cuticle thin, ~~2, with no visible intersecting fibers, of equal width over the entire body. Lateral notochords narrow, width over most of the body about one-fifth to on-sixth the body diameter with cells in 2 or 3 rows. Ventral notochord with very large cells in 2 rows, well developed the entire length of the body. Dorsal notochord with nuclei in the cells distinct only at the anterior end of the body and in the tail; elsewhere the body is syncytial. Nuclei not perceptible. Amphids small, pore-like; they open at the level of the head papillae and slightly dorsad to it. Oral cavity terminal, stroma narrow. Gullet with a sharp odontostyle about 18 long. Diameter 2. Length of the gullet not determined, but could not be traced more than one-third the body length. The trophosome starts behind the nerve ring and ends in front of the spicules. Two spicules, clearly divided in half from the base, arched, their diameter at the base 12 to 13, narrow slightly at the apex and carry small spines on the tip. Spicules about 150 long. Genital papillae in 3 rows; about 18 in the middle row behind the cloaca and 16 each in the lateral rows. The papillae are more numerous in front of the cloaca, the exact number not determined, but in the middle row they extend 200. Tail slightly pointed, slightly bent in ventrally, gently convex dorsally; 210 long. (ref. ID; 7870)

Type specimens

The holotype male in preparation No.11658 is kept in the Collection of the Zoological Institute, USSR Academy of Sciences, Leningrad. (ref. ID; 7870)

Type locality

Ukrainian SSR, cold spring (11.2 degrees C) south of the city of Chuguyev, June 11, 1971 (V.V. Polishchuk). Host unknown. (ref. ID; 7870)

Measurements

Male: Length 22.5 mm, a=206, b=?, c=110. (ref. ID; 7870)