THE SOLDIERLESS TERMITES OF AFRICA 61 



This species is separable from its nearest relations, A. comis sp. n., A. concilians 

 (Silvestri) and A. eumenus sp. n. in the imago by its weakly inflated postclypeus 

 and longer apical teeth of the mandibles. The worker is larger than A. comis and 

 A. eumenus, with differently proportioned mandibles, and in A. concilians the fore 

 tibia is less inflated and the apical teeth shorter. The abdomen of the worker caste 

 does not appear to be dehiscent in A. arnicas. 



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

 Tanzania: Amani, 21. iv. 1950 (P. B. Kemp Coll. No. 384), in British Museum 

 (Natural History). 



Only the type nest-series of this species is known. 



There is no information on its biology. 



Astalotermes benignus sp. n. 



(Text-figs 59, 60, 69, 70 & 83-88; PI. 1, fig. 3) 

 [Anoplotermes lateralis (Walker); Silvestri, 1914 : 65. Misidentification.] 



Imago. Head capsule dark sepia-brown, very dark above ocelli; fontanelle small, brown, 

 elongate oval, weakly ridged in middle, running forwards into groove through medial spot; 

 medial spot sepia-brown, oval, slightly ridged on each side of groove that continues forward 

 into depressed triangular area behind postclypeus; postclypeus sepia-brown, labrum yellow- 

 brown; frontal marks brown, semicircular, distinct, very slightly depressed; antennae brown. 

 Pronotum, meso- and metanota sepia-brown, transverse dark sutures present; legs, femora 

 and tibiae yellow-brown, tarsi yellow. Abdominal tergitcs brown, with sepia-brown stigmata, 

 sternites pale brown with brown stigmata; cerci pale brown. 



Posterior margin of head capsule evenly rounded; ocelli medium-sized, separated from com- 

 pound eyes by two-fifths to two-thirds own least diameter; postclypeus moderately inflated, 

 Pcl/W, 0-26-0-30, Pc1/Ra, 306-3-63, posterior margin evenly rounded, median suture weak, 

 absent anteriorly. Apical teeth of mandibles short, La/Li, 0-50-0-57, R A /Ri, 0-71-0-82: 

 subsidiary marginal tooth of left mandible just clear of molar prominence in surface view, 

 La/Li. L m , 11-13-12-40; points of apical and marginal teeth of right mandible in line, anterior 

 edges of marginal teeth equal. Pilosity of head capsule yellow-brown, very uneven, no pelt. 

 Fore tibia with vestigial third spur sometimes extremely difficult to find. 



Measurements (three specimens from two localities) in millimetres. 



Head width across eyes (W) . 

 Ocellus (O w xOi). 

 Ocellus to eye (O-E) 

 Postclypeus length (Pel) 

 Antennal article 1 1 1 

 Antennal article IV 

 Antennal article V 

 Left mandible, apical to first 



marginal (La) • • • 0-06 — 



Left mandible, first to third 



marginal (Li) . . . o-io-o-n 0-107 



Left mandible, third marginal 



to molar (L m ) . . , 0-04-0-05 0-046 



Range 





Mean 



0-69-0-73 





0705 



•05-0-06 x 007- 



-0-08 



0055 x 0-077 



002-003 





0030 



0-19-0-21 





0195 



003 





— 



003-004 





0-033 



003-004 





0033 



