Aristocleidus lacantuni, Mendoza-Franco & Osorio & Caspeta-Mandujano, 2015

Mendoza-Franco, Edgar F., Osorio, Marina Tapia & Caspeta-Mandujano, Juan Manuel, 2015, Two new species of Aristocleidus (Monogenea) from the gills of the Mexican mojarra Eugerres mexicanus (Perciformes, Gerreidae) from southwestern Mexico, Parasite (Paris, France) 22, pp. 1-6 : 3-4

Aristocleidus lacantuni n. sp.

urn:lsid:zoobank.org:act:6A4D7AD9-B9D8-48E7-85FF-37A182476C2D

Type-host: Eugerres mexicanus (Steindachner, 1863) ( Perciformes , Gerridae ).

Site of infection: Gill lamellae.

Type locality and collection date: Rio Lacantún basin (16°09 0 96.6 00 N, 90°95 0 56.9 00 W), August 2014.

Specimens deposited: holotype, three paratypes in CNHE (9875 and 9876, respectively) .

Etymology: named after the location (i.e., Rio Lacantún) from which this species was found.

Description ( Figs. 9–14 )

Diagnosis (based on four specimens) includes the following: Body 302–342 long; greatest width 90–102 usually near body midlength. Cephalic lobes well developed; each head organ comprising groupings of terminations of cephalic-gland ducts. Pharynx 27 wide, subspherical to elongate ovate. Testis ovate; seminal vesicle comparatively large, fusiform; prostatic reservoir pyriform. Copulatory complex 27 (23–30; n = 4) long. MCO comprising proximal funnel-shaped base, coiled tube loose, comprising about 0.5 poorly defined ring, appearing U-shaped; poorly defined Z-shaped accessory piece. Germarium 44–48 long, 16 wide; vaginal tube short, opening on left side of the body, poorly sclerotized (not depicted); vitellarium dense, vitelline ducts not observed. Haptor 55–58 wide. Ventral anchor 26 (25–28; n = 7) long, with straight shaft and elongate arcing point, base with fused roots, ventrally bent; base 10 (9– 11; n = 7). Dorsal anchor 36 (35–38; n = 7) long, with elongate superficial root with a small distal knob-like extension, short to non-existent deep root, slightly arced shaft, elongate recurved point. Ventral bar 26 (24–28; n = 3) long, with conspicuous anteromedial process with terminal horn-like ornamentation; dorsal bar 25 (22–29; n = 3) long, straight, rodshaped. Hook 11 (10–13; n = 10) long; FH loop about 60% shank length.

Differential diagnosis

The morphology of the haptoral and copulatory sclerites of this species clearly allows its formal generic assignment within Aristocleidus . A. lacantuni n. sp. resembles A. hastatus and A. lamothei in the length of the copulatory complex, i.e., 23–30 vs. 27–36 and 22–26, respectively. It differs from these latter species as well as A. mexicanus n. sp. and Aristocleidus sp. in having shorter anteromedial process of the ventral bar (comparatively larger in A. hastatus , A. mexicanus n. sp., and Aristocleidus sp. and indistinct in A. lamothei ) and a ventral anchor with straight shaft and elongate arcing point (point and shaft united at a conspicuous angular bend in A. hastatus and Aristocleidus sp. , evenly curved shaft and point in A. lamothei , and elongate arcing shaft and straight point [slightly angular union] in A. mexicanus n. sp.) [ 8, 11].

Figures

Figures 9–14. Haptoral and copulatory complex sclerites of Aristocleidus lacantuni n. sp. from the gills of Eugerres mexicanus. 9: dorsal anchor; 10: ventral anchor; 11: ventral bar; 12: dorsal bar; 13: hook; 14: Copulatory complex. Figures are drawn to the following scales: 20 µm (Figs. 9–12 and 14) and 5 µm (Fig. 13).