Haliotrema guttati, García-Vargas, Fernando & Fajer-Ávila, Emma J., 2008

García-Vargas, Fernando & Fajer-Ávila, Emma J., 2008, Two new species of Dactylogyridae (Monogenoidea) on rose spotted snapper, Lutjanus guttatus (Osteichthyes: Lutjanidae), from the coasts of Nayarit and Sinaloa, Mexico, Zootaxa 1729, pp. 61-68 : 62-63

Haliotrema guttati n. sp.

( Fig. 1 )

Type host: Lutjanus guttatus ( Lutjanidae, Osteichthyes ) (Rose spotted snapper).

Site of infestation: gills

Type locality: Pacific coast of Mazatlán, Sinaloa, México (23°29'N; 106°36'W).

Other locality: Cruz de Huanacaxtle, Nayarit, México (20°44’N, 105°22’W).

Type specimens: Holotype and paratypes specimens were deposited in the National Helminthological Collection ( CNHE) of Mexico (Cat. No. 5730, holotype and 5731, paratypes), Instituto de Biología, Univesidad Autónoma de México ( UNAM). Other paratype and voucher deposited in the Harold W. Manter Laboratory Collection (Cat. No. 48568, paratype and 48569, voucher) University of Nebraska State Museum.

Etymology: The specific name, guttati , is derived from the species designation of the type host.

Prevalence and mean abundance: 28%, 1.4 (n=19).

Description: Tegument smooth, body 356 (271-489, n=13) long, fusiform, greatest width 96 (80-125, n=13) at level of testis. Terminal cephalic lobe poorly developed, two lateral lobes moderately developed; three pairs of cephalic organs presents. Two groups of four cephalic glands located posterolateral to pharynx. Eye-spots four, posterior pair slightly closer and larger than anterior pair; accessory pigmented granules around anterior pair. Pharynx semispherical, 29 (23-35, n=13) wide, 22 (20-28, n=13) long. Esophagus short. Ceca confluent posterior to gonads. Peduncle broad. Haptor almost rectangular 78 (60-90, n=12) long, 74 (65- 80, n=12) wide. Anchors dissimilar with a conspicuous bulge before the curvature of point and shaft. Ventral anchor 48 (42-57, n=19) long with well-developed roots; inner root slightly longer than outer root; shaft lightly curved with a prominent bulge in inner face; point long, acute projecting over inner root; base 48 (30- 42, n=19). Dorsal anchor 59 (52-65) long, with elongate inner root, lacking outer root, deeply fenestrate, shaft less sharply curved than ventral anchors, with bulge near the curve, inner root pointed; base 28 (20-35, n=19). Ventral bar 47 (38-62, n=9) long, W-shaped. Dorsal bar 43 (38-53, n= 11) long, inverted W-shaped, with knob at both extremes. Fourteen marginal larval hooks similar; each 13 (12-15, n=28) long, with terminally depressed thumb, delicate point, slightly curved shank.

Male copulatory organ trumpet-shaped, 67 (55-95, n=13) long, tubular, broader at conical base. Accessory piece membranous enveloping basal third of copulatory organ. Testis oval 40 (30-54, n=13) long, 36 (28-48, n=13) wide. Vas deferens arises from anterior end of testis, loop left intestinal ceacum, distended in its middle region forming an elongated seminal vesicle. Germarium oval 36 (30-50, n=11) long, 33 (25-46, n=11) wide. Vagina 14 (10-20, n=11) long, 12 (10-15, n=11) wide; vaginal aperture dextromarginal, funnel-shaped, hidden by a rounded muscular corpus. Vaginal canal short, running directly to elongate seminal receptacle. Vitelline follicles dense throughout trunk, less dense in region of reproductive organs.

Remarks: The general morphology and haptoral armament of Haliotrema guttati n. sp. resembles that of H. longihamus Zhukov, 1976 and H. heteracantha Zhukov, 1976 . The new species differs from H. longihamus by having a simple fenestrated dorsal anchor in contrast with the double one found in H. longihamus . The shape of the dorsal and ventral bars and the morphology of copulatory organ also are different; H. longihamus has similar dorsal and ventral bars but they are more slightly straight with the ends poorly developed, while H. guttati has ventral and dorsal bars that are different (the ventral bar is a wide W-shape and the dorsal bar an inverted W-shape, with ends of each well developed). The male copulatory organ of H. guttati has a membrane that is sail-shaped at the distal part of cirrus, a structure that is absent in H. longihamus and H. heteracantha . The organism described in this study also is distinguished from H. heteracantha by the absence of a rounded membranous wing on the outer roots of dorsal and ventral anchors.

Figures

FIGURE 1. Haliotrema guttati n. sp. A. Whole mount (dorsal view); bar = 50 µm. B. Ventral bar. C. Ventral anchors. D. Dorsal bar. E. Dorsal anchors. F. Hook. G. Copulatory organ; bar = 20 µm. H. Haptor detail; bar 30 µm.