54 



T. ZIEGLER AND J.B. RASMUSSEN 



Fig. 7 Crotaphopeltis tornieri, asulcal view of hemipenes of ZMUC 

 R631147. 



Contrary to this condition the hemipenes of ZMUC R63 1205-6 

 and R631208-10 (Msolwa area, Rubeho Mts., Tanzania) have, in 

 addition to the three enlarged spines, a ring consisting of variously 

 enlarged spines on the asulcate surface of the middle truncus. A 

 similar condition was found in the hemipenes of ZMUC R63921 

 (Magombero Forest, ca. 50 km S Mikumi, Tanzania). 



Crotaphopeltis tornieri (Fig. 7). In situ hemipenes extend to 

 subcaudal scute no. 7-11 (x=8.4, n=27)(Rasmussen, 1993a; unpubl.). 



The pedicel of the hemipenis of C. tornieri is covered with tiny 

 spines except for a longitudinal depression on the asulcate surface. 

 Lower truncus usually with some enlarged spines. Distal to the 

 enlarged spines, the spines become smaller towards the apex, which 

 is terminally calyculate. Sulcus spermaticus is not forked and leads 

 directly to the apex ending in a terminal extension. 



In specimens from East and West Usambara Mountains the largest 

 spine is on the outside of the lower truncus, the second largest on the 

 asulcate surface. The spine ornamentation of the hemipenes of the 

 West Usambara population was somewhat variable, in the hemipenes 

 of ZMUC R63963 (Rasmussen, 1993: fig. 2) no distinctly enlarged 

 spine could be found on the asulcate surface. 



In some specimens (ZMUC R63 1 245 and R63 1 252) from Kilanzi- 

 Kitungulu Forest Reserve, Udzungwa Mountains, the enlarged spine 

 on the outside of the lower truncus is relatively small; furthermore 

 an enlarged spine on the asulcate surface is scarcely detectable. In 

 other specimens (ZMUC R63 1244, R63 1253-4 and R63 1256) from 

 the same area, various enlarged spines are present on the lower 

 truncus. 



In specimens from Kihanga River, Udzungwa Scarp Forest Re- 

 serve (ZMUC 631269-70) and from Rungwe Mission, Mount 

 Rungwe (ZMUC 631257), only the enlarged spine on the outside of 



the lower truncus is easily seen. On the asulcate surface some 

 enlarged spines are present. 



DISCUSSION 



The hemipenial structures of Crotaphopeltis share several characters. 

 e.g., pedicel largely covered with tiny spines, lower truncus with 

 enlarged spines, spines decrease in size distally, apex calyculate, 

 sulcus spermaticus unforked and leading directly to the apex. Regard- 

 ing the simple and stout to elongate hemipenes within Crotaphopeltis, 

 principally the differences in ornamentation of the (lower) truncus 

 seem to offer a clue as to separate these taxa, in spite of the relatively 

 large interspecific variation displayed. 



Crotaphopeltis barotseensis principally has one moderate en- 

 larged spine on each side of the sulcus in the hemipenes of the single 

 specimen examined. The species has a restricted distribution in 

 Central Southern Africa and is easily distinguished from sympatric 

 C. hotamboeia by general morphology (Rasmussen, 1985) as well 

 as hemipenial morphology. 



Hemipenes of Crotaphopeltis braestrupi have two to three slightly 

 enlarged spines on the truncus, one on each side of the sulcus and an 

 inconspicuous one on the asulcate side. Comparing the hemipenes 

 of C. braestrupi with those of sympatric C. hotamboeia from Kenya 

 and Somalia, Rasmussen (1985) stated: 'The ornamentation is also 

 very different. In C. braestrupi the hemipenis is covered with 

 slender spines, of which three are somewhat enlarged. In C. 

 hotamboeia the hemipenis is covered with stout spines of which 

 three basal ones are strongly enlarged (Rasmussen, 1985: fig. 9).' It 

 is difficult to judge the form of the variable spines (slender versus 

 stout), which depend on the condition and the method of preparation 

 of the hemipenes, but the three distinctly enlarged spines on the 

 lower truncus are nonetheless characteristic of the hemipenes of C. 

 hotamboeia across its entire distribution, i.e., Sub-Saharan Africa. 

 Further studies are needed to show whether a separate taxon is 

 justified for the specimens from Msolwa and Magombero Forest in 

 Tanzania which, in addition to the three enlarged spines, have a ring 

 consisting of some distinctly enlarged spines on the asulcate side of 

 the hemipenes. External morphological investigations so far do not 

 support such an assumption (Rasmussen, in prep.). 



The hemipenes of Crotaphopeltis degeni usually bear two (speci- 

 mens from Tanzania) to several enlarged truncal spines (specimens 

 from Cameroon, Ethiopia, Sudan, Uganda). Concerning the truncal 

 spines of the hemipenes of Crotaphopeltis degeni from Sudan 

 Rasmussen (1997) stated, 'up to six enlarged, stout spines, one each 

 side of the sulcus and two to four (usually three) more or less 

 enlarged spines on the asulcate aspect of the organ'. The lower 

 truncal spines of the hemipenis of a specimen from Lake Rukwa, 

 Tanzania appear only slightly enlarged, most probably due to ever- 

 sion after fixation. Rasmussen (1997) observed only two enlarged, 

 proximal spines in the incompletely everted hemipenes of speci- 

 mens from Kenya and Uganda. Crotaphopeltis degeni apparently 

 has a disjunct distribution like that of Causus resimus (Spawls and 

 Branch, 1995). Despite the intraspecific variation of this taxon it is 

 easily distinguished from sympatric C. hotamboeia and parapatric 

 C. hippocrepis by hemipenial morphology and as well as general 

 morphology (Rasmussen et al., 2000). 



The hemipenes of Crotaphopeltis hippocrepis are characterized 

 by the possession of two distinctly enlarged spines, each followed 

 by a row of accessory spines decreasing in size apically. This unique 

 ornamentation of the hemipenes seems fairly constant within the 

 entire distribution area (West Africa) of C. hippocrepis and the 

 species seems to be homogeneous (Rasmussen et ah, 2000). 



