Biospeedotrema jolliveti, Bray, R. A., Waeschenbach, A., Dyal, P., Littlewood, D. T. J. & Morand, S., 2014

Bray, R. A., Waeschenbach, A., Dyal, P., Littlewood, D. T. J. & Morand, S., 2014, New digeneans (Opecoelidae) from hydrothermal vent fishes in the south eastern Pacific Ocean, including one new genus and five new species, Zootaxa 3768 (1), pp. 73-87 : 75-76

Biospeedotrema jolliveti n. sp.

( Fig. 1 )

urn:lsid:zoobank.org:act:5F4B8936-D162-4F77-9D80-240E32DCAD02

Type host. Ventichthys biospeedoi Neilsen, Møller & Segonzac (Ophidioformes: Ophidiidae ), East-Pacific ventbrotula.

Site.? intestine (not given)

Type locality. South East Pacific Rise, hydrothermal vent site Oasis, 17°25.38’S, 113°12.29’W; Biospeedo cruise, submersible Nautile, R/V Atalante, dive PL 1582, baited trap B2, depth 2586 m, 22 April 2004, Biospeedo labels: 1582–2, 1582–5.

Type specimens. MNHN holotype 1 slide MNHN HEL 373; paratypes 3 wholemount slides MNHN HEL 374 375 376, 5 section slides MNHN HEL 377 378 379 380 381; BMNH paratypes 2013.12.3.4-6.

GenBank numbers. rDNA KF733985 , rDNA KF733988 .

Etymology. This species named after Dr. Didier Jollivet who led the Biospeedo expedition.

Description. Based on 7 whole-mounts and 2 sets of serial sections specimens. Measurements and ratios in Table 1. Body small, broadly pyriform ( Fig. 1 ). Tegument unarmed. Oral sucker subglobular, subterminal. Ventral sucker rounded to oval, much larger than oral sucker, centre just pre-equatorial. Prepharynx short, dorsal to oral sucker. Pharynx large, subglobular. Oesophagus distinct, thin-walled, long, sigmoid. Intestinal bifurcation about equatorial, dorsal to ventral sucker. Caeca blind, wide, divergent, reaching just past testes, not to posterior extremity.

Testes two, oval to pyriform, transversely elongate, symmetrical to slightly oblique, in anterior hindbody. Cirrus sac claviform, reaches to about mid-ventral sucker. Internal seminal vesicle saccular. Pars prostatica long, narrow, surrounded by gland-cells. Ejaculatory duct short. Genital atrium distinct. Genital pore median to slightly dextrally submedian, immediately anterior to ventral sucker.

Ovary oval to subtriangular, just anterior to or overlapping right testis, overlapping ventral sucker. Details of female proximal system disrupted in sections by eggs. Seminal receptacle uterine. Laurer’s canal opens dorsally at about level of posterior margin in ventral sucker. Mehlis’ gland ventral to ovary. Uterus reaching between testes, or just into post-testicular region, then passes sinistrally over dorsal surface of ventral sucker. Eggs large, tanned, operculate, relatively few. Metraterm not distinct. Vitellarium follicular, in lateral fields from pharynx or oral sucker to just into post-testicular region, narrow band confluent or approaching in region of testes, mainly lateral to caeca, but encroaching dorsally.

Excretory pore terminal, in slight notch. Vesicle short, flattens into broad vesicle just posterior to testes. Remarks. The features differentiating this species from its congeners are discussed below.

Figures

FIGURES 1 – 4. 1. Biospeedotrema jolliveti n. sp. ventral view of holotype. 2. Biospeedotrema parajolliveti n. sp., ventral view of holotype. 3. Biospeedotrema biospeedoi n. sp. a. Ventral view of holotype. b, c. Illustration of variation in body-shape. 4. Caudotestis ventichthysi. n. sp. Ventral view of holotype, cirrus-sac obscured by eggs. Abbreviations: C, caecum; CS, cirrussac; E, egg; Ov, ovary; T, testis; V, vitelline follicle. Scale-bars: 1, 3 a, b, c, 4, 200 µm; 2, 100 µm.