Chauhanellus neotropicalis, Domingues, Marcus V. & Fehlauer, Karin H., 2006

Domingues, Marcus V. & Fehlauer, Karin H., 2006, New species of Chauhanellus (Monogenoidea, Platyhelminthes) from the gills of Southern Atlantic marine catfishes (Siluriformes, Ariidae) of the Neotropical region, Zootaxa 1365, pp. 61-68 : 63

Chauhanellus neotropicalis n. sp.

( Figs 1–7 )

Type-host and type locality: Aspistor luniscutis (Valenciennes, 1840)

Site: Gills.

Type-locality: Fish market, Municipality of Paranaguá, State of Paraná, Brazil (1996).

Specimens deposited: Holotype, MZUSP 6357; 8 paratypes, CHIOC 36823 a–b, MZUSP 6358 a–d, USNPC 98921.

Etymology: The specific name is related to the first record of Chauhanellus for the marine Neotropical region.

Description (based on 9 adult specimens): Body 680 (n=1) long, fusiform, greatest width 131 (122–139; n=2) usually at level of germarium. Tegument smooth. Cephalic lobes moderately developed; three pairs of head organs; cephalic glands posterolateral to pharynx. Eyes 4; posterior pair slightly larger and closer than anterior pair; accessory granules absent in cephalic area. Mouth subterminal, midventral; pharynx ovate, 39 (36–43; n=2) in diameter; esophagus short; intestinal ceca two, nonconfluent, lacking diverticula. Haptor subspherical, 113 (108–118; n=2) long, 128 (113–144; n=2) wide. Anchors dissimilar; ventral anchor 54 (50–60; n=7) long, base 43 (30–50; n=7) wide, robust, with truncate superficial root, deep root expanded into wings, recurved shaft, short slightly recurved point. Dorsal anchor 62 (55–66; n= 7) long, base 30 (26–35; n=7) wide, robust, with inconspicuous superficial root, expanded deep root, evenly curved shaft and point; anchor spine blunt. Ventral bar 9 (n=2) long, 73 (72–74; n=2) wide, posterior ends with foot-like protuberances for articulation with ventral anchors. Dorsal bar, V-shaped, with spines on both ends, elongate posteromedial process. Hooks similar in shape, 16 (14–17; n=14) long, with erect thumb, evenly curved, shaft, point, shank without inflation, filamentous hook loop (FH loop) about half shank length. Male copulatory organ sclerotised, a coiled tube with 1 ¼ counterclockwise rings, 135 (110–155; n=8) long; male copulatory organ base with sclerotised margin, distal acute tip, proximal ring diameter 29 (23–39; n=4). Accessory piece, comprising a long sheath. Testis 58 (91 (74–108; n=2) long, 58 (55–60; n=2) wide, pyriform; seminal vesicle sigmoid; prostatic reservoir spherical. Germarium 70 (55–84; n=23) long, 30 (29–31; n=2) wide, elongate. Ootype not observed. Vaginal aperture dextral, vagina muscular. Seminal receptacle transversely pyriform. Vitellaria coextensive with caeca. Eggs not observed.

Remarks: Chauhanellus neotropicalis n. sp. differs from all other congeneric species by the combined presence of the following features: (1) male copulatory organ, a coiled

Figures

FIGURES 1 – 7. Chauhanellus neotropicalis n. sp. 1. Holotype, ventral view. 2. Copulatory Complex. 3. Hook. 4. Ventral bar. 5. Dorsal bar. 6. Ventral anchor. 7. Dorsal anchor. Fig. 1. scale 100 µm; Figs. 2 – 7 scale of 25 µm.