BEETLES OF THE GENUS MYOCHROUS — BLAKE 7 



ville, Tex. This group is unique in not having a toothed prothorax. 

 The aedeagi of intermedins and severini are strikingly alike, and the 

 chief differences in the group are in the scales and punctation. On the 

 Pacific coast are two closely related species, M. longulus LeConte and 

 M. whitei, new species, differing from the others in their slender shape 

 and long, wide scales. About the Gulf of Mexico are three reddish- 

 brown species, M. floridanus Schaeffer, which goes as far north as 

 Virginia, M. magnus Schaeffer, from Texas and Mexico, and M. tibialis 

 Jacoby, whose range extends from Mexico to Panama. These three 

 also have similarly shaped aedeagi. In the northern islands of the 

 West Indies are species from Cuba, Puerto Rico, Jamaica, and Haiti 

 that vary a little from each other much as do the species in the squamo- 

 SU8 group. From the southern islands of Barbados, Grenada, and 

 Trinidad comes a species, M. harhadensis Blake, that is found in 

 northern South America and has close relatives in Central America 

 {M. coenits, new species, from Panama, and M. femoralis Jacoby, 

 from farther north in Mexico, Guatemala, and Honduras). These 

 species all have a thorax covered with round deep punctures and an 

 aedeagus with a broad apex and a short, broadly rounded point. In 

 Panama is a species having an aedeagus with a peculiar scooplike tip 

 unlike any other, and in Peru and Ecuador occurs a beetle with a 

 similar sort of structure. Externally the two beetles are very much 

 alike in shape and in having a very densely and coarsely punctate 

 surface. In South America, where the genus takes on unusual 

 characters, there is a group of three species of which M. curculionoides 

 Lefevre is the most aberrant. This has two pronounced elevations 

 on the anterior margin of the thorax that elsewhere in the group is 

 greatly thickened. All three species differ from the others in having 

 a narrowly convex thorax, elytra with unusually distinct basal callos- 

 ities, and a pale band of scales at the apex. Still another group is 

 composed of three small mottled species, all very much alike. The 

 first ranges from Mexico through the Canal Zone to northern Colombia, 

 the second is found along the northern coast of South America 

 through the Guianas and Venezuela to Brazil, and the third occurs 

 in Bolivia and Paraguay. 



In North America there are very few species, aside from the squmno- 

 sus group, that stand out as being very unusual. M. ranella, new 

 species, with its heavy, pinched-in thorax, is mildly unique. In 

 Central America there is more divergence in the genus. But in South 

 America are found most strikingly different beetles, and up to the 

 present, at least, many of them quite unlike any others. Such are 

 M. explanatus Baly, the largest and flattest of the genus ; M. amiatus 

 Baly, another large one with an extraordinarily long slender point 

 on the aedeagus; M. bolivianus, new species, a queer chunky species. 



