112 WATT 
Aedeagus (Figs 15, 25-29,33-41,67,69,79-82,84,93,94,95,99,103,104). Koch (1955) 
has made the most extensive study of aedeagus in Tenebrionidae, and _ his 
morphological nomenclature has been followed in this study (Fig.15). The 
following terms are equivalents (cf. also Sharp & Muir 1912). 
Apicale = apical piece of tegmen (i.e. fused parameres). 
Basale = basal piece of tegmen. 
Penis = median lobe of aedeagus. 
In Mimopeus the aedeagus is not inverted as in many tenebrionids. When 
retracted into the abdomen the tegmen lies above the median lobe, and when 
extended the whole structure curves around beneath the abdomen, so that the 
tegmen lies beneath the median lobe (Fig.70.). In the shape and proportions of the 
aedeagus (see figures) there is considerable variation between and even within 
species (Figs.25-28), but all show the same basic structure. 
On apicale, parameres barely separated at apex, sometimes fused almost to 
apex. Dorsal and lateral surfaces of apicale bear scattered fine sensory setae and 
sensilla. Inflected alae extend ventrally towards base for over half the length of 
basale and form, with the inflected alae of the latter, a fairly complete tube around 
the penis. 
Sides of basale strengthened by fairly heavily sclerotised supports. Inflected 
alae extending entire length of basale, most extensive at about mid-length. There is 
an internal U-shaped slender ridge just distal to the basal margin, presumably 
providing attachmement for a muscle. 
Penis simple, without lacinia. Base supported by lateral sclerotised pieces; 
dorsal surface membranous at the base, becomes sclerotised anteriorly, while 
sclerotised alae become inflected onto the ventral surface. Inner groove runs along 
par. 
‘ 
Fig.15. Mimopeus opaculus. Aedeagus, Left. Dorsal. Right. Lateral. 
a. apicale, b. basale, par. paramere, p.penis. 
