456 SEEEICOENIA. 



ATHOUS. 



Athous, Eschscholtz, in Thon's Archiv, ii. 1, p. 33 (1829); Candeze, Monogr. Elat. iii. p. 416 ; Cat. 



Method. Elat. p. 150 *. 



A genus containing a very large number of species, all but four of which are from 



the Palaearctic or Nearctic regions. From America, south of the United States, three 



only have hitherto been described — one from Mexico, one from Ecuador, and one from 



Chili. The genus, however, proves to be fairly well represented in Mexico and 



Guatemala, whence ten are now recorded. The Central - American species belong 



to two well-defined groups — one with the third tarsal joint lamellate, and the other 



with the tarsi simple; some of those appertaining to the first group differ from all 



their allies in the very long and acute hind angles of the thorax, the angles being 



strongly recurved in A. photinoides and A. campanulatus. The first group will 



probably have to be separated eventually from Athous ; the genus, however, already 



includes species with the second and third tarsal joints more or less lamellate. The 



species here referred to Athous agree in the following characters : — front excavate, 



prominent, truncate or emarginate (A. carinicollis) at the apex ; antennae with the 



third joint small, the fourth and succeeding joints subequal in length ; posterior coxal 



plates narrow, gradually widening inwards ; tarsi simple, or with the third joint 



lamellate, the basal joint elongate. Amongst the new species here described, 



A. photinoides may be known by its mimetic resemblance to the Lampyrid genus 



Photinus, and A. carinicollis by the transversely carinate thorax. 



a. Tarsi with the third joint lamellate, the fourth very small ; front truncate or 

 feebly emarginate. 

 a'. Hind angles of the prothorax very elongate, acute. 

 a". The angles not or obsoletely carinate. 



a"'. Prothorax transverse, with the hind angles strongly recurved at the 

 tip, the sloping lateral portions velvety-pubescent ; body black, the 

 prothorax rufous, with two black vittae, the last two ventral segments 

 yellow ; antennae with the joints from the third broad and strongly 



serrate photinoides. 



b'". Prothorax longer than broad ; body brown. 



a*. Hind angles strongly recurved at the tip; prothorax campanulate, 



rather coarsely punctured campanulatus. 



A 4 . Hind angles less elongate, scarcely recurved at the tip; prothorax 



more parallel, more finely punctured mexicanus. 



b". The angles distinctly carinate, slightly recurved at the tip; prothorax 



longer than broad, subcampanulate ; body browu ■ . . aguinoctialis. 



* For the synonymy, see Candeze, he. cit. 



