Homalometron moraveci, Bray & Justine & Cribb, 2007

Bray, Rodney A., Justine, Jean-Lou & Cribb, Thomas H., 2007, Homalometron moraveci n. sp. (Digenea: Apocreadiidae) in the yellowfin goatfish, Mulloidichthys vanicolensis (Valenciennes, 1831) (Perciformes: Mullidae), from New Caledonia and the Great Barrier Reef, with a checklist of digeneans of Mulloidichthys species, Zootaxa 1525 (1), pp. 41-49 : 43

Homalometron moraveci n. sp.

( Figs 1–3 )

Type-host: Mulloidichthys vanicolensis (Valenciennes, 1831) , Mullidae , yellowfin goatfish.

Site: Digestive tract.

Type-locality: Fish market, Nouméa, allegedly from off Bouraké, Commune de Boulouparis , New Caledonia (21°58’S, 166°00’E) (21/09/2006) .

Other locality: Swain Reefs, Great Barrier Reef (21°53’S, 152°21’E, Feb., 2003).

Prevalence: New Caledonia, 25% (1 of 4); Swain Reefs, 100% (1 of 1).

Type-specimens: New Caledonia: Holotype MNHN JNC1966-1 , paratypes MNHN JNC 1966-2–8, BMNH 2007.5.1.1–5, QM G223078 ; Swain Reefs: paratypes QM G223079 , BMNH 2007.5.1.6.

Etymology: The species is named for Dr Frank Moravec (Č eské Budĕjovice, Czech Republic) in recognition of his major contributions to fish parasitology, and as he was involved in the collection of the specimens.

Description. Based on 11 complete worms and several fragments from New Caledonia and 2 well-developed, but non-ovigerous, worms from Swain Reefs. Measurements in Table 1. Body-elongate, narrow. Tegument spinous, spines reach to posterior extremity, sparse in hindbody. Pre-oral lobed short or absent. Oral sucker subglobular, mouth subterminal. Ventral sucker rounded to oval, slightly to distinctly larger than oral sucker. Forebody relatively short. Prepharynx long. Pharynx oval, small. Oesophagus distinct. Intestinal bifurcation in mid-forebody. Caeca long, narrow, terminate blindly, unequal, slightly separated from posterior extremity.

Testes two, oval with long axis longitudinally, entire, tandem, contiguous to distinctly separate, in midhindbody. Seminal vesicle oval, about halfway between ventral sucker and ovary. Pars prostatica long, narrow, sheath of gland cells difficult to distinguish from other gland-cells scattered in parenchyma, some evidence in some specimens of slightly denser packing of cells in this region, enters hermaphroditic duct distinctly posterior to ventral sucker. No ejaculatory duct or cirrus detected. Hermaphroditic duct long, narrow, passes dorsally to ventral sucker, distinctly into hindbody ( Table 1). Genital pore opens in median line immediately anterior to ventral sucker.

Ovary subglobular to oval, pretesticular, contiguous with or slightly separated from anterior testis. Seminal receptacle canalicular, oval, mostly pretesticular. Laurer’s canal opens dorsally to ovary. Mehlis’ gland preovarian. Uterus preovarian, intercaecal. Metraterm not strongly differentiated, starts at about posterior level of seminal receptacle, walls narrow. Eggs few, large, operculate, with thin, tanned shells. Vitellarium follicular, anterior extent in region of seminal vesicle, ventral, dorsal and lateral to caeca, not overlapping gonads, may have gaps at or around ovarian level, confluent dorsally and ventrally in post-testicular region.

Excretory pore terminal. Vesicle I-shaped, reaches almost to posterior testis. Lymphatic vessels not detected.

Figures

FIGURES 1–3. Homalometron moraveci n. sp. 1. Holotype, ventral view, New Caledonia. 2. Ventral view, immature specimen, Swain Reefs. 3. Terminal genitalia, lateral view, New Caledonia. 4. Proximal female system in immature specimen, Swain Reefs, dorsal view. Abbreviations: LC, Laurer’s canal; M, metraterm; O, ovary; PP, pars prostatica; SR, seminal receptacle; SV, seminal vesicle; T, testis; U, uterus; V, vitellarium; VR, vitelline reservoir. Scale-bars: 1, 2, 1000μm; 3, 200μm; 4, 100μm.