92 W. A. SANDS 



It appears to fill an equivalent ecological niche to T. togoensis with which its 

 distribution only marginally overlaps, and its exclusion from the Guinean and Sudan 

 vegetation zones may result partly from the biotic barrier caused by this similarity. 



Trinervitermes geminatus (Wasmann) 



(Text-figs. 231-234, 248, 249, 270-275, 385 ; Map 21) 



Euteymes geminatus Wasmann, 1897 : 170. Type locality : Ghana. 



Termes (Eutermes) geminatus (Wasmann) Desneux, 1904a : 42. 



Euteymes geminatus Wasmann ; Sjostedt, 1904 : 40, 44. 



Euteymes (Tyineyviteymes) geminatus Wasmann ; Holmgren, 191 2 : 64. 



Euteymes [Tyineyviteymes) gyossus Sjostedt, 1924b : 493. Type locality : Mauritania 



(probable), " Cote Atlantique du Sahara ". syn. n. 

 Tyineyviteymes grossus (Sjostedt) Sjostedt, 1926 : 342. 

 Tyineyviteymes geminatus (Wasmann) Sjostedt, 1926 : 343. 



Tyineyviteymes ebeneyianus Sjostedt, 1925a : 73. Type locality : Sudan, " Tanguru ". syn. n. 

 Tyineyviteymes ibidanicus Sjostedt, 1926 : 347. Type locality : Nigeria, Ibadan. syn. n. 

 Tyineyviteymes ebeneyianus Sjostedt ; Sands, 1957 : 24. 



Imago. Head capsule, central part of frons and vertex brown to dark chestnut brown, 

 vertex with three diverging yellow-brown streaks ; postclypeus, labrum, anterior part of frons 

 behind postclypeus and in front of ocelli, area surrounding antennae and eyes and extending to 

 a point behind eyes also paler, orange-yellow to yellow-brown. Antennae orange-yellow to 

 orange. Pronotum orange-yellow to brown. Meso- and metanota, other thoracic sclerites and 

 legs yellow to yellow-brown. Abdominal tergites brown to chestnut brown round stigmata, 

 slightly paler in middle, distinctly paler towards lateral margins ; sternites yellow to yellow- 

 brown, shaded brown round stigmata. Wings translucent very pale yellow-brown to brown, 

 subcosta and radius sector yellow to yellow-brown, partially outlined brown at base, membrane 

 behind radius sector with yellow to orange streak, rest of venation narrowly yellow-brown to 

 brown. 



Posterior margin of head capsule behind eyes much less than semi-circular, slightly sinuate 

 immediately behind eyes ; fontanelle distinct, paler than head, V- or inverted A-shaped, some- 

 times slightly depressed posteriorly, lateral arms often but not always dilated terminally ; area 

 of fontanelle usually partly occluded posteriorly by pigmented cuticle only slightly paler than 

 head, length including occluded portion approximates to twice breadth at base of lateral arms ; 

 eyes oval, moderately prominent in proportion to own diameter, and medium-sized relative to 

 head width, W/E index 2-7-3-0 ; ocelli medium sized to large, oval, separated from eyes by one- 

 sixth to nearly one-third own least diameter ; postclypeus moderately inflated, width 2-4-2-8 

 times length, anterior margin slightly concave or sinuate, rarely nearly straight, posterior 

 margin convex, rounded ; molar plate of right mandible with 7-8 ridges, antennae usually 17 

 segmented, II, IV, V, and VI subequal, VI slightly longer, III longer up to nearly twice these, 

 sometimes divided to produce 18 segmented forms. 



Pale coloured " scent " gland on anterior margin of fifth abdominal sternite of $ medium 

 sized, 0-64 to o-8omm. wide, 015 to o-i8mm. long ; cerci of $ female shorter than or equal to 

 width across base, conical. 



Pilosity on vertex consists of short curved setae of rather even length tending to form a 

 " pelt " or " mat ", with scattered setae 3-5 times as long. (Text-fig. 385.) 



Measurements (31 specimens from 5 localities) in millimetres. 



