Dactylogyrus jaculus Guégan, Lambert & Euzet, 1988

Musilová, Na Ď A, Ehulková, Eva Ř & Gelnar, Milan, 2009, Dactylogyrids (Platyhelminthes: Monogenea) from the gills of the African carp, Labeo coubie Rüppell (Cyprinidae), from Senegal, with descriptions of three new species of Dactylogyrus and the redescription of Dactylogyrus cyclocirrus Paperna, 1973, Zootaxa 2241, pp. 47-68 : 59-60

Dactylogyrus jaculus Guégan, Lambert & Euzet, 1988

( Figure 10 )

Type host and locality: Labeo coubie , Niger River (Bamako), Mali.

Other record: Labeo coubie, Baoulé River (Missira), Mali ( Guégan et al. 1988).

Present records: Labeo coubie , Gambia River near the hotel Simenti (sand beach 13° 01.543’N; 13º 17.471’W, gravel beach 13º 01.395’N; 13º 17.350’W), Mare de Simenti (13º 01.790’N; 13º 17.608’W), Gambia River near the Campement du Lion (13º 01.493’N; 13º 14.491’W), Niokolo-Koba National Park, Senegal.

Site: Gill lamellae.

Type specimen: Holotype MNHN HC 263.

Material examined: 5 unflattened and 10 flattened specimens in GAP.

Comparative material examined: Dactylogyrus jaculus Guégan, Lambert & Euzet, 1988 : holotype MNHN HC 263 (Tj 204) from Labeo coubie ; Dactylogyrus cf labeous Paperna, 1979: 2 vouchers RMCA M.T. 35.516 D and F from Labeo coubie .

Material deposited: 2 vouchers MNHN HEL 90 (Th 189), 91 (Th 190).

Description: Body length 345 (284–415; n = 5); greatest width 86 (79–98; n = 5) usually near midlength. Haptor 73 (69–82; n = 5) long, 88 (74–104; n = 5) wide. Single pair of anchors (dorsal): inner length 35 (33– 36; n = 10); outer length 23 (22–24; n = 10); inner root 15 (14–17; n = 10) long; outer root 2 (1–2; n = 10) long; point 11 (10–12; n = 10) long. Two bars: dorsal bar 17 (16–19; n = 10) long, 3 (n = 10) wide; ventral bar 8 (7–8; n = 10) long, 1 (1–2; n = 10) wide. Hooks 7 pairs, dissimilar in size; hook lengths (n = 7): pairs I, V = 17 (16–18); pair II = 18 (17–19); pairs III, IV = 20 (19–21); pairs VI, VII = 17 (15–18). Needles (1 pair) located near hooks of pair V. Vagina sclerotized, poorly defined, 6 (5–7; n = 6) long. Copulatory organ composed of tube and articulated accessory piece; total length 27 (26–29; n = 10); tube trace-length 26 (25– 27; n = 10).

Remarks: Although the hooks of the present specimens of Dactylogyrus jaculus Guégan, Lambert & Euzet, 1988 are slightly longer than those described in the original description (i.e., 15–21 vs 14–18), based on our examination of the holotype of D. jaculus we consider our specimens to be conspecific with the above species. However, we disagree with the decision of these authors to synonymise D. jaculus with D. cf labeous (see Guégan et al. 1988), which was proposed by Paperna (1979) based in part on the type specimens of D.

labeous Paperna, 1969 , collected from L. coubie in Ghana. Our detailed comparison of 2 voucher specimens of D. cf labeous with our specimens of D. jaculus revealed that they significantly differ in the size of the hooks (12–14 vs 15–21, respectively) and in the morphology of the copulatory organ (compare Figs. 10 and 12 ).

Figures

FIGURE 10. Dactylogyrus jaculus Guégan, Lambert & Euzet 1988. A. anchor; B. ventral bar; C. dorsal bar; D. hooks; E. needle; F. vagina; G. copulatory organ.

FIGURE 12. Dactylogyrus cf labeous Paperna, 1979 from Labeo coubie (voucher RMCA M. T. 35.516 D). A. anchor; B. ventral bar; C. dorsal bar; D. copulatory organ. Hooks and needles poorly defined.