Tribe 4. Euplectini, sensu latiore 



After considerable study of the American fauna I have combined the 

 Euplectini, sensu strictiore, and the Trichonychini into a single tribe. 



Apparently the only character separating these two aggregates concerns the 

 tarsal claws. Thus Raffray (1903, 1908) says of Euplectini "tarsi with a single 

 or principal claw, and at times also an accessory, claw-like hair" and of Trich- 

 onychini "two unequal claws on each tarsus, the small or accessory claw is 

 curved, and not to be confused with a hair." Bowman (1934, p. 2) says of 

 Euplectini "inner tarsal claw absent or exceedingly minute" and of Trichony- 

 chini "inner tarsal claw very small but distinct, at least one-fifth as long as the 

 outer." 



These differences are insufficient to separate two groups of genera which 

 inhabit much the same zoogeographic range, the same ecological niches, and 

 resemble each other in many basic morphological features. If the claw formula 

 was rigid, with one group having one claw and the other group having two 

 claws, the two aggregates could be separated for practical purposes; this still 

 would not demonstrate a fundamental arrangement. Leng (1920) followed 

 Raffray in using both tribes; such a course was proper, since Raffray 's opinion 

 held, will always hold, great authority, but as data accumulate such a course 

 becomes less advisable. American students of the family have not found the 

 employment of both tribes wholly profitable. Thus, early workers, such as 

 Brendel and Wickham (1890) and the brilliant Casey (1893, p. 442 and 1897, 

 p. 552) opposed such a course; recently Bowman (1934, p. 8) separated the two 

 groups with apparent reluctance, since he felt that a still further break-up of 

 the euplectines might be justifiable "especially if the Trichonychini be re- 

 moved." 



Casey bitterly opposed separation of these two groups of genera, and his 

 remarks in one instance (1893) will bear quoting: 



"The tribes or groups Euplectini and Trichonychini of Reitter and Raffray 

 cannot be maintained as distinct and natural aggregates of genera, and should 

 be united to form the single tribe Euplectini. The auxihary (tarsal) claw varies 

 by successive degrees in different genera and species otherwise closely related 

 so that it is impossible to draw any line of demarcation between two groups 

 founded upon this character or any other which it seems possible to discover. 



The second tarsal claw is distinctly visible as a minute hair-like appendage 

 in at least several species of European Euplectus, in Trimiopsis, and also in 

 Actium, which was recently re-described by Mr. Raffray under the name 

 Proplectus and placed in the "Trichonychini". I have seen the second rudi- 

 mentary claw plainly in Bibloporics bicanalis and Euplectus calif omiciis. 

 Finally in {Ramecia crinita) the auxiliary claw becomes as large, conspicuous 

 and fully formed as in Trichonyx itself, and yet in general habitus and 

 details of structure crinita is unmistakably very closely allied to Euplectus, 

 and should be not widely separated from that genus. 



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