4 



W 



A. SANDS 





Right mandible, second marginal 









to molar (R m ) 





o-o8-o-n 



0094 i 001 5 



Mesonotum width (M) 





o-43-o-53 



0464 ± 0-034 



Metanotum width (N) 





o-39-o-56 



0441 ± 0059 



Worker. Head capsule pale yellow, pilosity sparse and long, yellow. Postclypeus moderately 

 inflated, Pcl/W, 0-29-0-31, Pcl/Ri, 2-38-2-60. Apical teeth of mandibles fairly long, La/Li, 

 0-71-0-79, Ra/Ri, 1-00-1-02; subsidiary marginal teeth of left mandible separated from molar 

 prominence by distinct notch in surface view, complex ratio, La/Li. L m , 11-40-12-55; apical 

 and marginal teeth approximately in line, anterior edge of first marginal distinctly longer than 

 that of second, R A /Ri.R m , 14-49-14-80. Fore tibia scarcely inflated, Tl/Tw, 5-33-5-42, third 

 apical spur distinct, about half length of other two. Mesenteric overlap at junction with 

 proctodeum diagonal, to right of malpighian knot; enteric valve seating lateral in unopened 

 abdomen, very weakly three-lobed, connected to second pouch of proctodeum by short neck; 

 membranous wall of valve beyond cushions with sparse minute spicules. 



Measurements (three specimens from three localities) in millimetres. 



Head width (W) . 



Fore tibia width (T w ) . 



Fore tibia length (Tj) . 



Postclypeus length (Pel) 



Left mandible, apical to first marginal (La) 



Left mandible, first to third marginal (Li) 



Left mandible, third marginal to molar (L m ) 



Right mandible, apical to first marginal (Ra) 



Right mandible, first to second marginal (Ri) 



Range 

 104-1-09 



015 

 0-80-0-81 



0-31-0-33 

 0-13-0-14 



0-18 



006 



013 



013 



Right mandible, second marginal to molar (R m ) 007 



All the necessary comparisons between A. prosenus and other members of the 

 genus have already been made in their individual descriptions. Astratotermes 

 prosenus has been made the type-species of the genus because it is the species most 

 distinct from related genera, and so least likely to sink in synonymy should adjust- 

 ments be needed in their membership in future. The abdomen of the worker 

 caste appears at least potentially dehiscent in A. prosenus. 



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

 Nigeria: Northern Region, 30 miles from Lokoja on Okene Road, 8.iii.i958 (W. A. 

 Sands Coll. No. S.2081) in British Museum (Natural History). 



Other paratype material. Nigeria : Northern Region, 6 m. from Gombe on Dadin 

 Kowa Road, 9.V.1957 and Samaru Regional Research Station near Zaria, 18.V.1959 

 (W. A. Sands). Imagos and workers in BMNH. 



This species has only been found in the surface layers of low, wide mounds at the 

 base of trees in Guinean savanna, probably built by Odontotermes species. Alates 

 were collected at light in May between 6.45 and 7.15 p.m. after an early shower 

 at the start of the rainy season. 



