82 W. A. SANDS 



6 Head capsule in plan view " shouldered " behind base of antennae ... 7 



- Head capsule outline various, not " shouldered " in front ..... 8 



7 Head capsule in profile rising from base of nose above antennal socket in almost a 



straight line to near highest point, before downward curve to occiput. Nose 

 always shorter than rest of head capsule, measuring from hind margin of antennal 

 socket (Text-figs. 338-343) ....... rapulum (p. no) 



- Head capsule in profile scarcely rising in a curve from base of nose to behind antennal 



socket, then commencing convex curve to highest point, continuous with down- 

 ward curve to occiput. Nose often equal, sometimes longer than rest of head 

 capsule, measuring as above, sometimes shorter (Text-figs. 344-350) 



rhodesiensis (p. 114) 



8 Hind tibia under 1 -39mm. in length ....... dispar (p. 87) 



- Hind tibia over 1 -39mm. in length ......... 9 



9 Paler coloured, head capsule yellow to ferruginous, nose darker, orange to chestnut 



brown, with paler tip. West Africa, N. Congo, Sudan, N. Uganda 



oeconomus (p. 105) 



- Darker coloured, head capsule ferruginous to pitchy brownish black, nose darker than 



head, chestnut brown to jet black with red tip . . . . . . 10 



10 Head capsule in profile rising from base of nose in front of antennal socket more or 



less straight to highest point of head, nose always shorter than rest of head 

 capsule. East Africa, Southern Congo, Angola . . . gratiosus (p. 97) 



- Head capsule in profile scarcely rising in a curve to behind antennal socket, then 



convex to highest point. Nose often equal to or longer than rest of head capsule. 

 West Africa, N. Congo, Sudan, N. Uganda .... trinervius (p. 127) 



11 Antennae 12-13 segmented. E. and Central Africa . . . bettonianus (p. 84) 



- Antennae 14 segmented. W. Africa, N. Congo, Sudan, N. Uganda . . . 12 



12 Middle abdominal tergites, seen in profile, with distinct (though minute) setae over 



entire surface. Colour of head capsule usually darker, ferruginous orange, to 



dark sepia brown, nose darker with red tip (Text-figs. 270-275) geminatus (p. 92) 



- Middle abdominal tergites, seen in profile, with setae so minute and pale as to appear 



absent except at high magnifications. Colour of head capsule usually paler, yellow 

 to ferruginous, nose darker, orange to chestnut brown, with paler tip (Text-figs. 

 290-296) .......... oeconomus (p. 105) 



Trinervitermes arabiae Harris 

 (Text-figs. 376-378 ; Map 3) 



Trinervitermes arabiae Harris, 1957 : 43°- Type locality : Western Aden Protectorate, 

 Dhala. 



The soldier caste of this species is indistinguishable taxonomically from T. 

 togoensis (Sjostedt), but the nearest recorded locality of the latter is in Uganda, a 

 distance of about 1,000 miles. In the absence of the imago caste and of examples 

 of the soldier from intermediate localities, I consider it undesirable to reduce T. 

 arabiae to a synonym at present. It may be noted however, that evidence from 

 other genera shows that species typically found in the Guinean to Sahel vegetation 

 zones (Keay et al., 1959, types 8, 16, 17, 20, and 25) also occur in South- West Arabia. 



