THE SOLDIERLESS TERMITES OF AFRICA 171 



Comparisons have already been made between A. pectinatus, A. ctcnopher and 

 A. muricatus. In the imago caste, A. rastratus and A. retifaciens have larger eyes 

 and ocelli closer together, than in A . pectinatus. The reverse is true of A . tranquillus, 

 which also has a more inflated postclypeus and vestigial third apical spur on the fore 

 tibia. A. sentosus has more even head pilosity, and a differently shaped fontanelle. 

 A. spinulatus has longer apical mandibular teeth, and narrower meso- and metanota. 

 In the worker caste, A. rastratus is difficult to distinguish from A. pectinatus, having 

 a slightly more inflated postclypeus and possibly a somewhat wider dilation at the 

 end of enteric valve cushion 1, though this may not be constant. The sclerotized 

 cup and fenestrated base of enteric valve cushion 1 distinguish A. sentosus, as well 

 as its smaller size. The longer apical teeth of the mandibles and slender spines on 

 enteric valve cushions 2, 3 and 4 distinguish A . spinulatus, also the more numerous 

 spines fringing cushion 1. In A. tranquillus the enteric valve armature is less well 

 developed, position 1 being only partly sclerotized and shorter. In A. retifaciens it 

 reaches the other extreme with elongated hooked spines in positions 2, 3 and 4. 



Holotype $ imago, paratype J and $ imagos and workers from type-colony, 

 Kenya: Kaptagat Forest, alt. 8,000 ft, 2.iv.i952 (W. V. Harris Coll. No. 826) 

 in British Museum (Natural History). 



Other paratype material. Kenya: Kaptagat, 3.^.1952 (W. A. Sands); Londiani, 

 alt. 8,100 ft, 18.ii.1954 (R. M. C. Williams). Uganda: Ruwenzori, Fort Portal, 

 1952 (H. A. Osmaston), alates and workers, all above in BMNH. Democratic 

 Republic of Congo: Kivu, Lwiro (two vials), 24, 5.x, Irangi, i°53'S., 28°28'E., 

 10. xi. 1963 (E. Ernst), workers only, in BMNH and Swiss Tropical Institute, Basle. 



All the biological information on this species points to its being an inhabitant of 

 the mounds of other species, either Cubitermes or Odontotermes, at considerable 

 altitudes. 



Ateuchotermes rastratus sp. n. 



(Text-figs 409, 410, 417, 418 & 439-444; PI- 5. figs 1-3) 



Imago. Head capsule chestnut-brown, darker above ocelli; fontanelle roughly circular, 

 slightly depressed, much smaller than ocellus, pale yellow-brown; medial spot circular, flat, 

 smaller than fontanelle, coloured as head; postclypeus paler than head, ferruginous chestnut- 

 brown, labrum yellow-brown; frontal marks, very indistinct fiat crescents, coloured as post- 

 clypeus; antennae yellow. Pronotum, meso- and metanota brown, transverse sutures virtually 

 absent; femora pale yellow-brown, tibiae and tarsi yellow. Abdominal tergites brown, dorsal 

 stigmata yellow-brown, sternites yellow-brown with middle and ventral stigmata paler; 

 cerci yellow. 



Posterior margin of head capsule slightly undulating, not quite evenly rounded; ocelli pro- 

 portionately fairly large, separated from large compound eyes by less than half own least 

 diameter; postclypeus moderately inflated, Pcl/W, 0-27-0-28, posterior margin bowed, not 

 evenly rounded, median suture distinct. Apical teeth of mandibles short, La/Li, 0-56-0-62, 

 Ra/Ri> 0-80-0-92; subsidiary marginal tooth of left mandible separated from molar prominence 

 by distinct notch in surface view, complex ratio, LA/Li-L m , 6-88-8-20; points of apical and 

 marginal teeth of right mandible in line, anterior edge of first marginal longer than that of 

 second. Meso- and metanota fairly wide at constriction, M/W, 0-30. Pilosity of head capsule 

 yellow-brown, rather long, forming slightly uneven pelt. 



