102 



E. WADE 



Fig. 10 The author's concept of the distribution of the species of Macroprotodon. 



pronounced in M. mauritanicus the reduction occuring at the 3rd to 

 the 16th ventral averaging at about the 10th (5.4%). M. abubakeri 

 exhibits a similar condition. The range in the position of the reduc- 

 tion for M. cucullatus in the region under investigation is narrower, 

 being from the 3rd to the 1 1 th ventral and averaging at around the 7th 

 ventral (3.7%). For the Libyan populations and those further east the 

 average positions of reduction occur progressively closer to the head 

 (Wade, pers. obs.) suggesting that at least between these populations 

 the differences are clinal. 



The differences in the position of reduction from 19 to 17 anterior 

 to the vent between the taxa, however are much sharper (Fig. 9). In 

 M. mauritanicus the position ranges from zero (i.e. no reduction) to 

 38 ventrals distance from the vent (x=10.5%), the majority exhibit- 

 ing positions of reduction much less distant. The range is widest in 

 M. abubakeri from the 3 to the 54 ventrals and the positions more 

 evenly distributed (x = 15.7%). The positions of reduction are the 

 most distant from the vent in M. cucullatus ranging from 25 to 7 1 

 ventrals, the most frequent being from 40 to 47 (x=28.6%). 



Characters such as labial-parietal contact dismissed by Wade 

 (1988), Busack & McCoy (1990) and infralabial counts overlooked 

 by Wade were found to be exceptionally valuable in the resolution of 

 the mauritanicus problem. The sample of Busack & McCoy, 1990 

 (Fig. lc) of 'M. c. mauritanicus'' (n=73) is a heterogeneous assem- 

 blage which includes material from the Balearics (n=8), northwestern 

 Algeria =M. abubakeri (n=9) and that which is assigned in this work 

 to M. cucullatus (n=33): only twenty two of the specimens from 

 northern Algeria and northern Tunisia are referrable to M. 

 mauritanicus. Populations here recognised as M. cucullatus (n=3) 

 and M. abubakeri (n=2) where they extended into Morocco were 

 assigned to M. c. brevis. These authors found supralabial-parietal 

 contact in 40/47% (L/R) of "M. c. mauritanicus'. This character in 

 the present study was found to sharply differentiate M. mauritanicus 

 from M. cucullatus . The species showed no intermediacy in any of 

 the diagnostic character states where they occur at Biskra, the only 

 known point of contact. The scatter diagram (Fig. 1 1 ) also shows the 



species to be well differentiated. Two specimens of M. mauritanicus, 

 SMF 20169 (closely resembling syntype MNHN 1994.2340, Fig. 

 4c.) and MHNG 2031.98 showed, in addition to undifferentiated 

 body patterns and the state of 6+3+II maxillary teeth, 6+3 infralabials 

 in conjunction with good supralabial-parietal contact. Two black 

 headed individuals of M. cucullatus MNCN 1802 (Fig. 3d) and one 

 originally from the Museo Civico di Storia Naturale di Milano (Jan 

 & Sordelli, 1966 Livr. 19e, PI. I, Fig. 3A) shared the following 

 states: a pronounced 'textilis' pattern, 6+4 infralabials and 

 supralabials separated widely from the parietals: the former pos- 

 sessed 6+4+II maxillary teeth as did presumably also the latter (lost 

 due to destruction of Jan's collection during the 2nd World War, Dr 

 M. Podesta, in litt.. 1998). Busack & McCoy (1990) found 23% 

 (n=16) of 'M. c. mauritanicus' to possess 'entirely' black heads. 

 Melanocephalism is rare in M. mauritanicus but common in M. 

 cucullatus (Table 2). 



Three specimens of M. mauritanicus from a sample of 83 were 

 found to possess an entire nuchal collar, the common state in M. 

 abubakeri, of which two (BMNH 59.3.29.17 Algiers and NMB 

 20 1 6 Medea) originated in boundary zones between the two species. 

 However both possessed the states of short postorbital streak and 

 less than 4 maxillary teeth in the series preceding the fang; indeed 

 the Medea specimen exhibited 6+2+II on both sides. In four other 

 specimens from Algiers, NMB 2422, MNHN 3735, ANSP 34847 

 and 34848 the nuchal collar was divided, supralabial-parietal con- 

 tact was pronounced but the infralabial state was equivocal (6+3 

 n=3, 6+4 n=2). By contrast in the nine specimens of M. abubakeri 

 from the same locality the nuchal collar was entire in all except 

 MNHN 3732 in wich it was divided: all possessed 6+4 infralabials 

 (6+5 on one side in one individual)whereas the supralabial-parietal 

 condition was equivocal (contact n=3, non-contact n=4 contact one 

 side n=2). 



The evidence presented above shows that M. mauritanicus and M. 

 abubakeri are distinct taxonomic entities and behave as good species 

 without any evidence of intergradation: both being distinguishable 



