Page:Memoirs on the coleoptera (IA memoirsoncoleopt01case).pdf/20

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Differs from any other described species of the subgenus in its more parallel and rather convex form.

This distinct species differs greatly from the preceding in the more elongate fifth tergite, which in lacustrina is only about as long as the fourth; also in smaller prothorax, narrower abdomen, larger eyes and other characters. The sex of the type is not evident.



The species of this subgenus are moderately large in size, of heavy build and unusually broad abdomen, this in the majority being fully as wide as the elytra. The antennæ in typical forms, such as the type (A. quadricollis Csy.), are long and rather strongly