THE SOLDIERLESS TERMITES OF AFRICA 165 



Right mandible, first to second mar- 

 ginal (Ri) ..... 010-011 



Right mandible, second marginal to 



molar (R m ) .... 005-006 



This is the smallest species of Ateuchotermes, although its known size range over- 

 laps with A. retifaciens. The latter is distinguishable in the imago by its large 

 ocelli, very close to the compound eyes, and in the worker caste by its very long 

 hooked enteric valve spines on cushions 2, 3, 4, together with the different position 

 of the subsidiary marginal tooth of the left mandible. The vestigial third spur 

 on the fore tibia, the large size and differently proportioned marginal teeth of the 

 right mandible distinguish the imago of A. tranqnillus, the worker of which is also 

 larger with a less well-developed enteric valve, particularly cushion position 1. 

 All the other imagos are larger, A . muricatus having the ocelli further from the eyes ; 

 A. pectinatus, A. rastratns and A. sentosus all have the anterior edge of the right 

 first marginal tooth longer than that of the second, and A. spinnlatus has longer 

 apical teeth and narrower meso- and metanota. In the worker caste, none of the 

 remaining species has the middle part of the dilated distal end of enteric valve 

 cushion 1 inflated, and armed with a second row of spines; they are all flat or concave 

 with scattered spines. The condition of this structure seen in A. ctenopher and 

 A. retifaciens would seem to represent the end point in specialization. 



Holotype queen, paratype workers from type-colony, Gabon: 18 km from 

 Makokou, 8.^.1962 (/. Deligne) in Musee Royal de l'Afrique Centrale, Tervuren. 

 (Paratype king and workers from type-colony in BMNH.) 



Other paratype material. Democratic Republic of Congo: Kwango River, 

 Takundi, 14. v. 1964 (G. Mathot), queen and workers, in Musee Royal de l'Afrique 

 Centrale, Tervuren. 



Both nest-series were collected from beneath nests of other species, the type- 

 colony beneath Crenetermes albotarsalis (Sjostedt) and the other paratypes from 

 a Cubitermes mound. The species is only known from the main Congo rain forest 

 block, the two records being from localities just over 450 miles apart. 



Ateuchotermes muricatus sp. n. 



(Text-figs 405, 406, 413, 414 & 425-431; PI- 5. %s 4-6) 



Imago. Head capsule sepia-brown, darker above ocelli and around compound eyes; fon- 

 tanelle oval or circular, smaller than ocellus, margins indistinct, sometimes approaching tri- 

 angular, flat or slightly depressed, brown or paler to near yellow- white ; medial spot circular, 

 flat, smaller than fontanelle, slightly paler than head; postclypeus sepia-brown, labrum brown; 

 frontal marks distinct, flat, semicircular, coloured as head; antennae pale brown. Pronotum, 

 meso- and metanota sepia-brown, transverse dark sutures weakly developed, particularly on 

 mesonotum; femora and tibiae pale brown, tarsi yellow. Abdominal tergites and sternites 

 brown, the latter paler in middle, dorsal and ventral stigmata both darker, sepia-brown; 

 cerci pale yellow-brown. 



Posterior margin of head capsule not evenly rounded, distinctly undulating; ocelli rather 

 small, separated from compound eyes by slightly less to rather more than own least diameter; 



