Haliotrematoides plectridium Kritsky & Mendoza-Franco

Kritsky, Delane C., Tingbao, Yang & Yuan, Sun, 2009, Dactylogyrids (Monogenoidea, Polyonchoinea) parasitizing the gills of snappers (Perciformes, Lutjanidae): Proposal of Haliotrematoides n. gen. and descriptions of new and previously described species from marine fishes of the Red Sea, the eastern and Indo-west Pacific Ocean, Gulf of Mexico and Caribbean Sea, Zootaxa 1970 (1970), pp. 1-51 : 37

Haliotrematoides plectridium Kritsky & Mendoza-Franco n. sp.

( Figs. 98–103)

Type host and locality: Spotted rose snapper, Lutjanus guttatus (Steindachner) (Lutjanidae) : off Taboga Island, Panama (8 o 49'N, 79 o 34'W), 24 May 2007.

Other record: Lutjanus guttatus (Lutjanidae) : Perlas Archipelago , Panama (8 o 22'N, 79 o 01'W), 24 May 2007 .

Site of infection: Gills.

Specimens studied: Holotype, USNPC 101367 ; 9 paratypes, USNPC 101368 , BMNH 2008.11.19.61-62, CNHE 6466 ; voucher specimen, USNPC 101369 .

Etymology: The specific name (a noun) is from Greek (pl ē ktron = a cock’s spur) appended to the diminutive ending (- idion) and refers to the spur on the shaft of the dorsal anchor.

Description: Body slender; greatest width usually at level of gonads. Cephalic lobes well developed. Eyespots lacking lenses. Pharynx subspherical. Testis ovate; vas deferens, seminal vesicle not observed. MCO comprising small funnel-shaped base, slightly tapered and coiled tubular shaft with angular bend near midlength, recurved tip; shaft with proximal sheath; coil counterclockwise. Prostate, prostatic reservoir not observed. Germarium irregular. Vaginal pore on small tegumental protrusion and associated with a series of internal ridges; seminal vestibule apparently absent; vaginal canal indistinct, apparently a broad unsclerotized tube leading to large seminal receptacle on body midline near level of anterior end of germarium. Ventral anchor with depressed superficial root, moderately long deep root, slightly curved shaft and recurved point; distal shaft and point with delicate superficial grooves. Dorsal anchor with base infrequently having a fleshy mass along its outer surface, a moderately long superficial root, inconspicuous deep root, straight shaft with inner proximal spur, recurved point; distal shaft and point superficially grooved. Ventral bar rod shaped, with two small subterminal pockets projecting from anterior margin, ends enlarged and directed posterolaterally; dorsal bar a broad U- or V-shaped rod. Hook distribution typical, except some hooks lying on trunk at level of posterior margin of testis.

Measurements: Body 397 (364–430; n = 2) long; greatest width 60 (56–63; n = 2). Haptor 69–70 (n = 1) long, 76–77 (n = 1) wide. Pharynx 20–21 (n = 2) wide. MCO 78 (71–86; n = 8) long. Ventral anchor 42 (39–45; n = 8) long; dorsal anchor 57 (54–60; n = 8) long. Ventral bar 38 (36–41; n = 7) long; dorsal bar 35 (31–37; n = 8) long. Hook 13 (12–14; n = 30) long. Germarium 30–31 (n = 1) long, 17–18 (n = 1) wide; testis 53 (43–62; n = 2) long, 30 (26–35; n = 2) wide.

Remarks: Haliotrematoides plectridium resembles H. cornigerum by having a spur on the inner surface of the proximal portion of the dorsal anchor shaft. They are easily differentiated in the comparative morphology of the MCO (with an angular bend near midlength of the shaft in H. plectridium ; lacking a bend in the shaft of H. cornigerum ).