Euryhaliotrema lovejoyi, Kritsky & Boeger, 2002

Kritsky, Delane C. & Boeger, Walter A., 2002, 41: New and previously described species of Dactylogyridae (Platyhelminthes) from the gills of marine and freshwater perciform fishes (Teleostei) with proposal of a new genus and a hypothesis on phylogeny, Zoosystema 24 (1), pp. 7-40 : 13-15

Euryhaliotrema lovejoyi n. sp.

( Fig. 2 )

TYPE SPECIMENS. — Holotype ( INPA 403 ); 4 paratypes ( USNPC 91377 , 91378 , INPA 404 , HWML 16424 ).

ETYMOLOGY. — This species is named for Dr Nate Lovejoy, University of Manitoba, Winnipeg, Manitoba, Canada, who kindly provided specimens of Plagioscion spp. from Peru and Venezuela.

TYPE HOST AND LOCALITY. — Gills of Plagioscion sp. (Sciaenidae) : Igarapé Zamula, Rio Negro near Barcelos, Amazonas, Brazil, 00°51’S, 62°46’W, 19.X.1996.

MATERIAL EXAMINED. — Plagioscion squamosissimus (Sciaenidae) : two voucher specimens, Caicara de Orinoco Fish Market (Orinoco River), Bolivar, Venezuela, IV.1999 ( USNPC 91380); voucher specimen, Belém Fish Market, Iquitos, Loreto, Peru, VII.1999 ( USNPC 91379).

DESCRIPTION

Body 375 (345-387; n = 4) long, fusiform; greatest width 99 (79-111; n = 4) usually at level of testis. Cephalic region broad; cephalic lobes moderately developed. Eyes subequal; members of posterior pair closer together than members of anterior pair; accessory granules uncommon in cephalic, anterior trunk regions. Pharynx subspherical, 24 (19-30; n = 4) in diameter. Peduncle tapered posteriorly; haptor subhexagonal, 65 (63-66; n = 3) wide, 56 (40-72; n = 4) long. Anchors similar; each with poorly defined deep root, elongate superficial root, evenly curved short shaft, point extending past level of tip of superficial root; superficial root of dorsal anchor frequently bent around tip of dorsal bar toward body midline; ventral anchor 19 (n = 2) long, base 11 (n = 2) wide; dorsal anchor 23 (n = 1) long, base 17 (n = 1) wide. Ventral bar 32 (n = 1) long, straight to broadly U-shaped, usually with delicate anteromedial muscle-attachment plate, posterior shield absent; dorsal bar 30 (n = 1) long, broadly V-shaped, with small delicate shield on posterior margin. Hook 13-14 (n = 2) long; shank delicate, uniform; FH loop about shank length. Copulatory organ 33 (30-38; n = 3) long, a loosely coiled tube of slightly less than one counterclockwise ring. Accessory piece 18 (16- 19; n = 4) long, comprising simple sheath; articulation process absent. Testis 60 (57-62; n = 2) long, 28 (25-30; n = 2) wide, ovate; seminal vesicle fusiform, anterior to seminal receptacle; two saccate prostatic reservoirs. Germarium subovate, 41 (30-54; n = 3) long, 27 (19-32; n = 3) wide; oviduct, ootype not observed; uterus delicate, ventral; vaginal aperture marginal; vagina with small distal funnel-shaped tegumental indentation, short dilated straight tube discharging into large transverse seminal receptacle anterior to germarium. Vitellaria dense.

REMARKS

Phylogenetic analyses suggest that the sister species of Euryhaliotrema lovejoyi n. gen., n. sp. is E. monacanthus n. gen., n. sp. The two species share the following features: a simple accessory piece in the copulatory complex, short vaginal canal, and similarly shaped ventral bars. Euryhaliotrema lovejoyi differs from E. monacanthus n. gen., n. sp. in having a dorsal anchor/bar complex (absent in E. monacanthus n. gen., n. sp.) and a copulatory organ comprising less than one ring (about two rings in E. monacanthus n. gen., n. sp.).

Figures

FIG. 2. — Euryhaliotrema lovejoyi n. gen., n. sp.; A, whole mount (composite, ventral view); B, vagina (ventral view); C, copulatory complex (ventral view); D, hook; E, ventral bar; F, dorsal bar; G, ventral anchor; H, dorsal anchor. Scale bars: A, 100 µm; B-H, 25 µm.