DESCRIPTION OF THREE NYBELINIA SPECIES 



127 



Fig. 4 Scolex of Nybelinia perideraeus sp. nov. from Glyphis gangeticus. 



Scale bar=150 urn. 



tentacular hooks by Shipley & Hornell (1906) and Pintner (1930) 

 were not unambiguous, he added with his own illustrations given in 

 figs 97- 1 00 a further type of tentacular armature for N. perideraeus. 

 He described a characteristic basal armature, where the hook form 

 changes from rose-thorn shaped in the basal part to slender spiniform 

 with sharply recurved tip in the metabasal part. Additionally, the 

 size of the scolex illustrated, 400-500 urn, is much smaller than that 

 given before for N. perideraeus. The illustrated specimens from C. 

 melanoperus correspond in scolex size and morphology as well as in 

 the detailed described tentacular armature to N. africana Dollfus, 

 1960 (compare Figs 97-100 in Dollfus (1942) with figs 10-19 in 

 Dollfus (1960). Thus, we consider both sets of material to belong to 

 the same species, N. africana Dollfus, 1960. 



Vijayalakshmi et al. (1996) described N. perideraeus from 

 Scoliodon palasorrah from India with a uniform tentacular armature 

 of minute curved hooks lOum long. The co-type material examined 

 in the present study demonstrates that the tentacular armature of N. 

 perideraeus is homeoacanthous heteromorphous with rose-thorn 

 shaped tentacular hooks of the same size along the tentacle. Thus, 

 the identity of the material described by Vijayalakshmi et al. (1996) 

 still needs to be clarified. 



The measurements and figures of the co-type specimen VNHM 

 2109 as well as the size of the tentacular hooks correspond closely 

 with those of N. dakari Dollfus, 1960 from the west African coast 

 and it is therefore considered synonymous with N. perideraeus. 

 Thus, Nybelinia perideraeus is the only species in subgrouping II Ab 

 of Palm et al. (1997), characterized by a homeoacanthous, hetero- 

 morphous metabasal armature without a characteristic basal armature 

 and basal tentacular hooks of similar size or bigger than in the 

 metabasal part of the tentacle. 



5a 



5b 





> 9 «» 



Fig. 5a-b Nybelinia perideraeus. a. metabasal tentacular armature, 

 internal surface, b. basal tentacular armature, external surface. 

 Abbreviation: B=bothridia. Scale bar=20 um. 



Kotorella pronosoma (Stossich, 1901) Euzet & 

 Radujkovic, 1989 



(Figs 7-9) 



Synonymy. 



Rhynchobothrium pronosomum Stossich, 1901 



Nybelinia pwnosomum (Stossich, 1900) Dollfus, 1930 



Otobothrium pronosomum (Stossich, 1900) Dollfus, 1942 



Tetrarhynchus herdmani Shipley & Hornell, 1906 of Southwell 



(1929a, b 1930) 

 Stenobothrium herdmani (Shipley & Hornell, 1906) Pintner, 1913 

 Nybelinia {Nybelinia) herdmani (Shipley & Hornell, 1906) Dollfus, 



1930 



MATERIAL EXAMINED. Type VNHM 2095, 1 adult from Himantura 

 imbricata (Bloch & Schneider, 1801) (=Trygon walga), Sri Lanka 

 (Ceylon) (collection of Shipley & Hornell); VNHM 2097, 1 adult 

 from Himantura imbricata, Sri Lanka (collection of Shipley & 

 Hornell). 



DESCRIPTION. Kotorella pronosoma was described in detail by 

 Euzet & Radujkovic (1989). The scolex measurements of K. 

 pronosoma together with the measurements of the type material of 



