230 



ACANTHOMERID.E 



II. ACANTHOMERID^. 



KiG. 159. — Acanthomera Heydeni 9 • x 1 j. 



Orthorrhaphous brachycerous eremochsetous flies of very large to 

 gigantic size. Antennae with an annulatecl flagellum (almost as in 

 Xylophagus) in the female, but with a comparatively short annulated 

 third joint ending a long arista in the male. TibicC with only a slight 

 spur on the middle pair. Wings large and broad ; prsef urea starting 

 only slightly before the base of the discal cell ; cubital fork wide open ; 

 fourth posterior cell bluntly closed. 



Head crammed on to tlie thorax, large and holoptic in the male as in Tabanus, and 

 still rather large and with the eyes not at all widely separated in the female. Face 

 somewhat similar to that of Lepti&, the middle part being distinct from its surround- 

 ings ; upper mouth-edge sometimes produced into a short snout j frons of the female 

 slightly depressed as in Leptis, not more than one-seventh the width of the head, and 

 the face not much wider at the mouth ^ frons and occipital collar bare ; ocelli con- 

 spicuous, on an elevated space. Palpi jointed, long and thin, lying against the 

 lower part of the sides of the face and then projected forwards in the female almost 

 as in Xylophagus. Eyes of the male with enlarged facets on the front and upper 

 parts. Antennaj closely approximated at the base ; two basal joints unusually 

 short ; third joint in the female flagelliform, 8-annulated, elongate, and ending 

 in a point ; but in the male (of at any rate some species) short and conical though 

 still annulated, and bearing a long setiform terminal arista which is much longer 

 than the third joint. 



Thorax with dense or coarse pubescence at the sides of the disc. Scutellum 

 unarmed ; metanotum very small. 



Abdomen with the basal five segments broad and flat, similar to that of 

 Stratiomys. Genitalia of the male small and inconspicuous, of the female consisting 

 of a many segmented apparently telescopic ovipositor. 



Legs only moderately strong or even slender, the tibiae and tarsi being specially 

 thin ; usually with a subfemoral (at about three-quarters the length) and an 

 anterior terminal si:»ine on the hind femora ; tibiie with a small indistinct spur on 

 the middle pair only ; touch hairs absent. Pulvilli three, pad-like ; claws com- 

 paratively small. 



