Prochristianella omunae, Beveridge & Justine, 2010

Beveridge, Ian & Justine, Jean-Lou, 2010, Two new species of Prochristianella Dollfus, 1946 (Platyhelminthes, Cestoda) from the blue-spotted stingray, Neotrygon kuhlii (Müller & Henle, 1841) off New Caledonia, Zoosystema 32 (4), pp. 643-652 : 646-648

Prochristianella omunae n. sp.

( Figs 3; 4)

TYPE MATERIAL. — New Caledonia, Nouméa, Îlot Maître (166°40’E, 22°34’S), from spiral valve of Neotrygon kuhlii (Müller & Henle, 1841) ( Rajiformes , Dasyatidae Jordan, 1888 ), 5.XI.2003, holotype ( JNC 957). — Same data, 7 paratypes ( MNHN JNC 957-958).

OTHER MATERIAL EXAMINED. — New Caledonia, off Nouméa, X.1998, 1 specimen ( MNHN JNC 1627).

ETYMOLOGY. — The specific name is an anagram of the collection locality.

DESCRIPTION

Small cestodes, gravid specimens 3.39-4.90 (4.15, n = 2) long with 5 (n = 2) segments. Scolex acraspedote, surface smooth, 692-1200 (908, n = 6) long; width in region of pars bulbosa 167-208 (188, n = 6); 2 sub-circular bothria, pars bothrialis 208-156 (240, n = 6), bothrial width 163-196 (179, n = 4); pars vaginalis 396-813 (596, n = 6); sheaths sinuous, arranged spirally in contracted specimens; bulbs elongate, extending to posterior margin of scolex; bulbs 325-470 (408, n = 6) long, 54-75 (65, n = 6) wide; bulb ratio 5.28-7.85 (6.27, n = 6); retractor muscle originates at base of bulb, origin surrounded by small number of gland cells; pre-bulbar organ present.

Everted tentacles up to 400 long, with prominent basal swelling; diameter in basal region 21-29 (25, n = 10), in metabasal region 17-21 (19, n = 10); hooks hollow.

Basal armature: first 2-3 rows of hooks enlarged, falcate,8-11 (9.9, n = 10) long, base 5-9 (6.9, n = 10); next 18 rows of hooks originating on antibothrial surface, terminating on bothrial surface; hooks smaller, triangular on bothrial, internal and external surfaces, tending to spiniform towards antibothrial surface, 2-5 (3.4, n = 10) long, base 2.0-3.5 (2.7, n = 10); slender, erect hooks on antibothrial surface 3-5 (4.3, n = 10) long, base 0.5-1.0 (0.6, n = 10) long; transition to metabasal armature occurs at about row 20.

Metabasal armature heteroacanthous, typical; hook rows begin on antibothrial surface of tentacle, terminate on bothrial surface. Distinct space between hooks 1 and 1’ on antibothrial surface of tentacle. Hook sizes increase from hooks 1(1’) to 3(3’) then gradually decrease in size; 13-15 hooks per principal row. Hooks 1(1’) large, uncinate, 7-10 (8.4, n = 10) long, base 5-8 (6.5, n = 5); hooks 2(2’) slender, falcate, 8-16 (11.8, n = 10) long, base 3-6 (4.7, n = 10) long; hooks 3(3’) slender, falcate, 10-15 (12.2, n = 10) long, base 3-5.5 (4.8, n = 10) long; hooks 4(4’) slender, falcate, 10-14 (11.9, n = 10) long, base 3-4 (3.4, n = 10) long; hooks 5(5’) falcate, shorter than hooks 4(4’), slender, 7-10 (7.9, n = 10) long, base 1-2 (1.9, n = 10) long; hooks 6(6’) larger, slender, spiniform, 4-7 (5.9, n = 10) long, base 1-1.5 (1.1, n = 10) long; hooks 7(7’)-15(15’) small, spiniform, 1.0-2.5 (1.8, n = 10) long, base 0.5-1.0 (1.8, n = 10).

Mature segments acraspedote, elongate, 562-1146 (792, n = 4) long, 146-229 (177, n = 4) wide; length/ width ratio 3.85-5.00 (4.40, n = 4). Testes visible in single segment only, 20 in number, arranged in 2 columns anterior to ovary; 3 testes posterior to genital pore, 6 anterior to genital pore, 11 on antiporal side of segment. Ovary at posterior extremity of segment, with 4 lobes, each lobe 188-271 (222, n = 3) long, 50-75 (58, n = 3) wide, with multiple lobules; Mehlis’ gland present between ovarian lobes; vitelline follicles circum- medullary, 25-68 (45, n = 10) in diameter; uterus tubular, median, extending to anterior extremity of segment; uterine pore absent. Gravid segments 1688-1825 (1754, n = 3) long, 279-438 (342, n = 3) wide; gravid uterus entirely filling medulla; eggs 16 in diameter, spherical, shell tanned.