Callorhynchocotyle callorhynchi ( Manter, 1955 )

Vaughan, David & Christison, Kevin, 2012, Towards addressing the current state of confusion within the Hexabothriidae Price, 1942 (1908): Callorhynchocotyle Suriano & Incorvaia, 1982 (Monogenea: Hexabothriidae) re-visited, with the preliminary evaluation of novel parameters for measuring haptoral armature of hexabothriids, Zootaxa 3229, pp. 1-34 : 18-22

Callorhynchocotyle callorhynchi ( Manter, 1955)

( Figs 7 , 8 , Tables 1, 2)

Synonyms. Squalonchocotyle callorhynchi Manter, 1955 (in part); Erpocotyle callorhynchi Dillon & Hargis, 1968 (in part).

Type host. Callorhinchus capensis (Duméril) ( Callorhynchidae , Holocephali). Type locality. Cape Town, South Africa.

Additional locality. Walvis Bay, Namibia ( Lebedev & Parukhin 1969); Off the Pategonian shelf ( Kuznetsova 1970: S. callorhynchi from Callorhinchus callorhynchus ; likely to be C. marplatensis ); West and South coasts of South Africa (present study).

Site on host. Gills.

Material examined. USNPC 037447.00: paratype 399-17; USNPC 080984.00: vouchers M1523-7, 9 and 10; QM: paratypes GL 10475-80; SAMCTA 29465 (15 whole mount vouchers), SAMCTA 29466 (10 haptor digest vouchers); AHC 29747 (10 whole mount vouchers); AHC 29478 (5 haptor digest vouchers).

Redescription. Total body ( Fig. 7 A) length (excluding haptor) 6885 ± 1214.5(5500–11100, n = 24), maximum body width 1700 ± 161.6(1425–2100, n = 24). Oral sucker ( Figs 7 A, B) internally papillate, diameter 360 ± 34.2(269–411, n = 24). Pharynx 91 ± 9.6(68–113, n = 24) long, 89 ± 7.0(75–100, n = 24) wide ( Figs 7 A, B). Branched intestinal caeca unite posterior to testes and extend into the haptor ( Fig. 7 A). Asymmetrical haptor 2494 ± 362.8(2025–3640, n = 24) long, 1595 ± 169.7(1275–1960, n = 24) wide with 3 paired sucker sclerite complexes. Haptoral suckers papillate.

Sucker sclerites of complex 3 ( Fig. 8 A): circumference length 1179 ± 57.8(1070–1320, n = 30); total length 530 ± 20.4(488–585, n = 30); total diameter 345 ± 16.5(310–374, n = 30); width 70 ± 5.7(61–81, n = 30); shaft length 476 ± 20.9(431–532, n = 30); inner diameter 277 ± 14.9(236–310, n = 30); aperture angle 57° ± 4.3(48°– 68°, n = 30); aperture 311 ± 24.7(257–357, n = 30); hook-side curve length 113 ± 9.1(96–132, n = 30) and shaftside curve length 119 ± 12.0(90–140, n = 30). Complex 3 sucker-sclerite hook length 168 ± 16.2(138–205, n = 30); hook curve length 37 ± 4.2(31–48, n = 30); aperture 135 ± 15.5(106–178, n = 30) and base width 43 ± 3.7(35–50, n = 30).

Sucker sclerites of complex 2 ( Fig. 8 B): circumference length 1191 ± 59.8(1076–1292, n = 30); total length 525 ± 19.4(484–558, n = 30); total diameter 351 ± 15.7(323–381, n = 30); width 66 ± 7.6(54–83, n = 30); shaft length 482 ± 19.5(441–520, n = 30); inner diameter 285 ± 13.5(255–310, n = 30); aperture angle 55° ± 4.4(45°– 67°, n = 30); aperture 305 ± 23.7(249–348, n = 30); hook-side curve length 110 ± 12.4(81–127, n = 30) and shaftside curve length 123 ± 13.4(89–145, n = 30). Complex 2 sucker-sclerite hook length 162 ± 19.2(118–191, n = 30); hook curve length 35 ± 4.2(28–41, n = 30); aperture angle 107° ± 6.8(89°–118°, n = 30); aperture 132 ± 17.3(93– 157, n = 30) and base width 40 ± 3.0(32–46, n = 30).

Sucker sclerites of complex 1 ( Fig. 8 C) smaller than similarly sized sucker sclerites of complex 2 and 3 with circumference length 858 ± 44.4(758–953, n = 30); total length 382 ± 19.5(347–428, n = 30); total diameter 246 ± 15.0(219–271, n = 30); width 40 ± 4.9(29–49, n = 30); shaft length 384 ± 19.6(347–432, n = 30); inner diameter 209 ± 14.1(183–235, n = 30); aperture 253 ± 25.6(199–306, n = 30); hook-side curve length 61 ± 5.7(50–71, n = 30) and shaft-side curve length 89 ± 11.6(74–111, n = 30). Complex 1 sucker-sclerite hook length 56 ± 4.8(44–65, n = 30); hook curve length 12 ± 1.8(7–16, n = 30); aperture 45 ± 4.9(32–54, n = 30) and base-width 14 ± 1.2(11–18, n = 30).

Dorsal haptoral appendix 1223 ± 183.7(918–1668, n = 20) long, 423 ± 62.5(248–509, n = 23) wide. Terminal suckers of appendix 293 ± 30.9(243–364, n = 44) long, 146 ± 15.6(118–188, n = 44) wide. Single pair of hamuli present before terminal suckers.

Hamulus ( Fig. 8 D) total length 63 ± 2.5(56–67, n = 25); hook point length 15 ± 0.8(13–16, n = 25); hook shank length 20 ± 1.4(16–22, n = 25) total diameter 31 ± 1.3(28–33, n = 25); hook distal point width 3 ± 0.3(3–4, n = 25); outer aperture angle 20° ± 1.3(16°–22°, n = 25); aperture 94 ± 5.6(82–105, n = 25); hook shank base width 7 ± 1.0(5–9, n = 25); inner root-shaft length 37 ± 2.2(33–43, n = 25); outer root-shaft length 47 ± 1.9(43–50, n = 25); root base angle 115° ± 14.1(86°–139°, n = 25), and root base width 26 ± 1.9(22–30, n = 25).

Testes irregular in shape, 88 ± 12.4(57–111, n = 22) in number; 82 ± 13.0(62–109, n = 18) wide. Vas deferens sinuous, surrounded by small gland cells along the majority of its length ( Fig. 7 C). Vas deferens loop proximal to entrance into cirrus absent in some specimens. Unarmed muscular cirrus total length 472 ± 67.2(356–623, n = 20); maximum width 74 ± 7.8(49–85, n = 20); distal bulb length 125 ± 21.8(76–175, n = 20), and distal bulb width 113 ± 7.9(97–131, n = 20).

Ovary (dextral = 17, sinistral = 7) 1110 ± 176.2(845–1527, n = 19) long, anteriorly branched, coiled posteriorly, ascending to oviduct, branching to sac-like, reduced seminal receptacle ( Fig. 7 C). Ootype smooth, leading to uterus, dorsal to ovary, ventral to vas deferens ( Fig. 7 C). Ovate eggs connected by tendrils at each pole. Eggs (in uterus) 173 ± 9.9(158–189, n = 9) long, 72 ± 4.0(65–77, n = 9) wide. Parallel vaginal ducts with glandulo-muscular distal portion and thin-walled proximal portion. Ventral vaginal pores muscular, lateral to proximal portion of cirrus. Follicular vitellarium originates posterior to vaginal pores. Excretory pores not observed.

Remarks. Collection of additional specimens from the West and South coasts of South Africa represents an extension of the known range of C. callorhynchi from Namibia round the Cape coast of South Africa past Cape Agulhas. The cirrus measurements of C. callorhynchi of Beverley-Burton & Chisholm (1990) did not agree with those taken from the voucher material examined for the present study. Subsequent personal communications with Leslie A. Chisholm revealed that their measurements were erroneous, and they should therefore not be used in future comparisons. Manter (1955) differentiated S. callorhynchi (synonym (in part) of C. callorhynchi ) from other members of Squalonchocotyle Cerfontaine, 1899 partly on the lack of a seminal receptacle in his specimens. Callorhynchocotyle callorhynchi does posses a small, smooth, reduced seminal receptacle, as do all members of the genus (Boeger et al. 1989).

Dillon & Hargis (1968) reported that the sucker-sclerite hooks of the type material from South Africa differed considerably in length to those of the additional material of E. callorhynchi (synonym (in part) of C. callorhynchi ) they collected off New Zealand’s South Island. Boeger et al. (1989) subsequently erected a separate species, C. amatoi Boeger et al. (1989) to accommodate all the New Zealand material based on differences in sucker sclerite morphology. In addition, Dillon & Hargis (1968) referred to the sucker sclerites of E. callorhynchi as having spines along the lateral margins, a feature repeated for other members of the family in the same publication. This feature is erroneous and is a misinterpretation of the lateral pits and indentations of the sucker sclerite (“parallel ridges” of Manter 1955).

The sucker sclerites of complexes 1, 2 and 3 in C. callorhynchi are shorter in total and shaft length than those of C. marplatensis . The hamulus total width, hook point and hook shank lengths are greater than that of C. marplatensis . However, the inner root-shaft length of C. callorhynchi is comparatively shorter. Callorhynchocotyle callorhynchi is differentiated from C. marplatensis in possessing papillate oral and haptoral suckers, and is found exclusively on the gills of Callorhinchus capensis off Southern Africa.

Figures

FIGURE 7. Callorhynchocotyle callorhynchi. A. Whole mount. B. Enlarged anterior section of whole mount. C. Enlarged mid-section of whole mount. Abbreviations: eci, everted portion of cirrus; gic, genito-intestinal canal; ut, uterus; vl, loop of vas deferens. Scale bars = 1000 µm.

FIGURE 8. Callorhynchocotyle callorhynchi sucker sclerites of complexes 1 (A), 2 (B) and 3 (C), and hamulus (D). Scale bars: A = 260 µm, B, C = 350 µm, D = 60 µm.