Euryhaliotrema perezponcei, 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 : 63-64

Euryhaliotrema perezponcei n. sp.

( Fig. 2 )

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. 5732, holotype and 5733, paratypes), Instituto de Biología, Univesidad Nacional 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: Euryhaliotrema perezponcei is named to recognize the great labor in the study of helminthes in Mexican fishes by Dr. Gerardo Pérez-Ponce de León.

Prevalence and mean abundance: 94%, 9.2 (n=19)

Description: Body small, fusiform, 305 (109-502, n=22) long; greatest width 125 (101-175, n=18), usually at testis level. Tegument serrate in posterior body. Three cephalic lobes poorly developed, one terminal and two laterals. Cephalic glands lateral or anterolateral to pharynx. Eyes-spots four sub-equals, members of posterior pair closer together than members of anterior pair; accessory granules common in the cephalic region. Mouth subterminal, midventral; pharynx sub spherical 34 (25-42, n=20) long, 33 (28-38, n=20) wide. Esophagus short, intestinal ceca confluent just posterior to testis. Peduncle short, connected to semihexagonal haptor 44 (40-48, n= 22) long, 84(56-90, n=22) wide. Anchors similar; each with well-developed, elongate inner root and short outer root, evenly curved shaft and sharp recurved point not extending past level of tip of superficial root. Ventral anchor 26 (24-30, n=28) long, 20 (15-25, n=26) wide; dorsal anchors with 28 (24-32, n= 33) long, 22 (18-26, n=33) wide at basal portion. Ventral bar 32 (24-36, n=19) long with flattened trapezoidal anteromedial projection and slightly expanded extremities. Dorsal connecting bar larger than ventral bar 38 (29-48, n= 19) long, inverted U-shaped with slightly enlarged ends. Fourteen larval similar hooks 12 (10- 15, n=51) long, with a slightly straight shaft, prominent thumb and straight shank and discrete point, filamentous hooklet, and short loop, at middle distance of shank length.

Male copulatory organ, including cirrus and accessory piece, 300 (249-352, n=17) long; cirrus 264 (225- 306, n=17) long with three counterclockwise coils, coil diameter 23 (15-30) and moderately large bulbous base. Accessory piece 36 (24-48, n=15) long, shaped like a perching bird. Testis semi-oval, 45 (38-60, n=12) long and 40 (32-55, n=12) wide, posterior to germarium. Vas deferens arising at region anterior to testis; looping around left intestinal caecum to base of copulatory organ; distended in middle region forming a sigmoid seminal vesicle. Single pyriform prostatic reservoir. Germarium elongated, slightly overlapping anterior ends of testis, 55 (32-85, n=14) long and 39 (30-52, n=14) wide. Mehlis’ gland anterior to germarium, with multiple posterior branches. Ootype immediately anterior to Mehlis’ gland. Short oviduct and one smooth uterus, often occupied by single large and triangular egg, 62 (59-62, n=5) long, 59 (57-59, n=5) wide. Vagina dextromarginal, 19 (15-25, n=9) long and 13 (10-15, n=8) wide, opening funnel-shaped. Vaginal canal narrow, connected to pyriform seminal receptacle lying anterior to germarium. Vitellaria in lateral regions overlapping intestinal ceca but not overlapping reproductive organs.

Remarks: The number of coils of the male copulatory organ of species of Euryhaliotrema species and the direction that the coils are wound are important taxonomic features for specific taxonomic classification. The copulatory organ of Euryhaliotrema perezponcei n. sp. has three counterclockwise coils, in contrast to E. chrysotaeniae (Young, 1968) Kritsky and Boeger, 2002 with four clockwise coils. Recently Pan and Zhang (2006) reported that the copulatory organ of E. xinyingense has three coils but their description and figures are not consistent and their diagnosis of this species requires reevaluation. The anchors, bars and vaginal shape of specimens of E. chrysotaeniae also are different from those of the new species described in this study. The outer root of the anchors of E. perezponcei is more developed than the poorly-developed anchors of E. chrysotaeniae . The bars of the new species are well-developed with more broad ends than those of E. chrysotaeniae for which both bars have smooth ends. Finally, the vaginal canal of E. perezponcei is shorter than that of E. chrysotaeniae in which it is large with a distal loop and ends at a funnel-shaped vagina.

Figures

FIGURE 2. Euryhaliotrema perezponcei n. sp. A. Whole mount (ventral view); bar = 50 µm. B. Ventral bar. C. Ventral anchors. D. Dorsal bar. E. Dorsal anchors. F. Hook; bar = 20 µm. G. Copulatory organ, a semiaxis major, b semiaxis minor; bar 20 µm H. Haptor detail; bar 30 µm.