Acleotrema diplobulbus ( Yamaguti, 1968 ) Dominques & Boeger, 2007

Acleotrema diplobulbus ( Yamaguti, 1968) Dominques & Boeger, 2007 View in CoL

Syn. Diplectanum diplobulbus Yamaguti, 1968

Heteroplectanum diplobulbus ( Yamaguti, 1968) Rakotofiringa, Oliver & Lambert, 1987 View in CoL

Figs 2A–H View FIGURE 2 , 6B View FIGURE 6

Host. Kyphosus vaigiensis (Quoy & Gaimard, 1825) ( Centrarchiformes : Kyphosidae ), brassy chub.

Locality. Off Puerto Santa Rosa (6°52’S, 79°55’W), Lambayeque, Peru, South America GoogleMaps .

Deposited material. 3 voucher specimens (MUSM 5518a–c)

Site in host. Gill filaments.

Redescription. Based on 3 specimens: 2 mounted in Gomori’s trichrome 1 mounted in Hoyer’s medium: Body elongate, fusiform, 575–896 (716; n =3) long; greatest wide 100–115 (106; n = 3) usually at level of testis. Scales not observed. Cephalic region narrow, with one terminal and 2 bilateral poorly developed cephalic lobes; 3 bilateral pairs of conspicuous head organs; bilateral pair of conspicuous unicellular cephalic glands posterolateral to pharynx. Two pairs of eye-spots present, equidistant; accessory chromatic granules absent ( Fig. 2A View FIGURE 2 ). Pharynx spherical, 28–46 (36; n = 3) in diameter; esophagus short; intestinal caeca unbranched, extending from anterior to near posterior end of trunk, not confluent posteriorly. Haptor differentiated from body proper, laterally expanded, 49–68 (57; n = 3) long, 157–182 (169; n = 3) wide. Anchors dissimilar ( Fig. 2B–C View FIGURE 2 ). Ventral anchor 31–37 (33; n = 3); with elongate superficial root; well-elongate, broad deep root, larger than superficial root; straight shaft with two lateral knob at base; and recurved point; point not surpassing level of tip of superficial root; 5 (5; n = 3) wide. Dorsal anchor 19–20 (20; n = 2) long, with inconspicuous superficial root; short deep root; slightly curved, broad shaft; and recurved point; surpassing level of tip of superficial root; base 6–8 (7; n = 2) wide. Ventral bar 127–151 (137; n = 3) long, elongate, with mid-ventral longitudinal groove, tapered ends ( Fig. 2D View FIGURE 2 ). Dorsal bars 51–73(59; n = 3) long, curved, with lateral projection ( Fig. 2E View FIGURE 2 ). Fourteen similar hooks, 8–10 (9; n = 3) long, each with depressed obtuse thumb, slender and slightly curved shank, and short point; filamentous hook (FH) loop about shank length; hook pair 1 at level of ventral bar; hook pair 5 at level of ventral anchor shaft, others submarginal pairs on lateral haptoral lobes ( Fig. 2F View FIGURE 2 ). Squamodiscs, similar, each 40–57 (49; n = 3) long; 82–92 (87; n = 3) wide, with 27 (27; n = 2) concentric rows; dumbbell-shaped rodlets ( Fig. 2G View FIGURE 2 ). Genital atrium sclerotized. MCO dagger-shaped, 34 (34; n = 3) long; MCO base ring-shaped; MCO surrounded by weakly sclerotized sac ( Fig. 2I View FIGURE 2 ). Ejaculatory bulb strongly muscular, oblong with elongate sclerotized internal tube. Testis ovate, 83–104 (93; n = 2) long, 59–70 (64; n = 2) wide; vas deferens not looping left intestinal caeca, dilating to form elongate sinuous seminal vesicle in left side of trunk, lateral to ovary; prostatic reservoir, prostatic glands not observed. Ovary elongate, pyriform, 40–60 (51; n = 8) long, 42–64 (51; n = 8) wide, looping dorsoventrally right intestinal caeca; uterus, oviduct, oötype not observed. Vagina tubular; seminal receptacle well developed ( Fig. 2H View FIGURE 2 ). Vitelline follicles dense, extending from posterior level of pharynx to posterior end of trunk, absent in regions of reproductive organs. Eggs not observed.

Remarks. This species was described by Yamaguti (1968) as Diplectanum diplobulbus Yamaguti, 1968 from the gills of Kyphosus cinerascens (Forsskål, 7175) in Hawaii.According to Yamaguti (1968), the main morphological characteristic of this species is the presence of two muscular ejaculatory bulbs. However, the examination of paratype and newly collected specimens of A. diplobulbus reveals the presence of a single ejaculatory bulb containing an elongated sclerotized internal tube. New illustrations and morphometric data for A. diplobulbus are provided, and this finding constitutes a new geographical record for this diplectanid.