A Survey of the Scorpion Fauna of South Africa. 101 
inferiorly. Hand usually very slender, the upper surface never separated 
by a keel into inner and outer portions. Fam. Buthidae. 
Only one spur (the anterior one) between the tarsus and protarsus of 
-each leg, and none between the protarsus and tibia of the third and fourth 
legs. Hand large, the upper surface usually divided by a finger keel into 
inner and outer portions ..... Fam. Scorinonidae 2 
2. The tarsus of each leg has a pair of rounded lateral lobes at the end, 
which lobes overlap the bases of the claws and often extend as far as the 
superior lobe or beyond. Tail strong, the first four segments normally with 
8 keels. Adults without a prominent lobe near the base of each finger. 
Sub-fam. Scorpioninae. 
The tarsus without a pair of rounded lateral lobes at the end, but 
sharply truncated on each side, the superior lobe projecting far beyond the 
lateral extremities of the segment. Tail rather weak, the lateral surfaces 
without well-developed keels. Normally there are 4 inferior caudal keels 
and 2 superior keels. Adults usually with a prominent lobe near the base 
of each finger ........ Sub-fam. Ischiiurinae. 
Key to the Genera of South African Scorpions. 
Fam. Buthidae. 
1. Two teeth on the lower margin of the immovable finger of the 
•chelicera. (Species usually large) ........ 2 
A single tooth on the lower margin of the immovable finger of the 
chelicera. (Species small) ......... 3 
No teeth whatever on the lower margin of the immovable finger of the 
chelicera. (Species small, or at any rate not large) . . . .4 
2. Abdominal tergites with three well-marked granular keels ; carapace 
with conspicuous granular keels symmetrically disposed ; movable digit 
with numerous median rows of teeth, the proximal tooth of each row 
enlarged and flanked on the outer side by another large tooth ; also with 
an inner series of isolated single teeth set in advance of those of the outer 
series ; basal pectinal tooth of adult female not enlarged. Buthus, Leach. 
Abdominal tergites with only a weakly developed median keel, the 
lateral keels obsolete or represented only by a granule posteriorly situated ; 
•carapace not keeled ; dentition of digit similar to that in Buthus ; basal 
pectinal tooth of adult female broadly dilated (except in P. granulatus). 
Parabuthus, Pocock. 
3. Movable finger with 6-7 main rows of teeth and 6-7 anterior 
flanking teeth, the enlarged one at the base of each main row flanked 
externally by 2 similar teeth ; basal pectinal tooth of female greatly en- 
larged ; abdominal tergites with three keels, but carapace though granular 
throughout is not keeled ; vesicle with a tubercle inferiorly near the base 
ot the aculeus ....... Pseudolychas, Kraepelin. 
