214 NORTH AMERICAN BLATTIDAE 



Attaphila fungicola Wheeler (Plate X, figures 5 and 6.) 



1900. Attaphila fungicola Wheeler, Amer. Nat., xxxiv, p. 860, figs. 3 to 6. [4 d', 

 2 9 , 60 juv'.; University of Texas, [Austin], Texas.] 



This, the smallest species of the known North American Blattidae, 

 is the only described form of the family found on this continent north 

 of IVIexico, in which pure symbiosis with ants occurs. The species 

 is treated fully by Wheeler; not only is a very thorough diagnosis 

 given, but its habits, environment and relationship with the 

 host, Atta fervens Say, are also discussed in detail. 



Characters of Male. — -(Austin, Texas.) Size minute; form stout, elliptical; ex- 

 posed surface clothed with scattered, rather elongate hairs. Head very broad, 

 occiput extensive and evenly convex, ocelli absent. Eyes vestigial, greatly reduced, 

 lateral, concealed except latero-ventrad by the latero-cephalic angles of the pro- 

 notum, and separated by a comparatively considerable distance from the antenna! 

 sockets. Antennae moderately stout; first joint about three times as long as its 

 basal width, second not as wide, with length equal to width, third slightly shorter, 

 succeeding joints increasing decidedly in length to eighth, of which the sixth is the 

 heaviest. 5" The joints beyond the first are carried normally at a decided angle to 

 it, laterad. Pronotum ample, evenly convex; cephalic margin straight, transverse, 

 rounding broadly into the divergent, weakly convex lateral margins, latero-caudal 

 angles bluntly rounded subrectangulate, caudal margin transverse, showing a slight 

 convexity. Tegmina rhomboidal, extending laterad slightly beyond base of first 

 dorsal abdominal segment, without trace of veins, at costal margins the more pro- 

 duced, rounding broadly into distal margins which are truncate, weakly oblique to 

 sutural margins, which slightly overlap. Wings vestigial pads, with weak traces 

 of venation. Dorsal abdominal segments unmodified, with lateral margins mod- 

 erately convex and latero-caudal angles broadly rounded. Supra-anal plate very 

 small, triangular, with apex bluntly rounded. Cerci represented by rounded lobes 

 scarcely longer than wide, dorsal surface deplanate, ventral surface convex. Sin- 

 istrad within the anal chamber, a delicate, slender, elongate genital hook is pro- 

 duced caudad,^'''' then curving sinistrad to apex which, due to the continued curva- 

 ture, is directed cephalad, the shaft expanding very slightly distad. Meso-dextrad, 

 adjacent to the genital hook, a sharp, straight, aciculate process is directed caudad.'" 



Characters of Female. — (Austin, Texas.) Agrees with male except in the follow- 

 ing features. Form decidedly broader, broadly oval. Tegmina and wings absent. 

 Mesonotum with latero-caudal angles rectangulate and sharply rounded; metano- 



3^' As observed by Wheeler, the antennae in this species are always incomplete, having 

 been clipped off by the host, Atta fervens. In the series before us the number of remain- 

 ing -joints in the different individuals ranges from i to 6 to 8 to 10. 



^*^ Normally this organ is wholly concealed, probably lying along the inner surface of 

 the subgenital plate. 



'■•^ This latter organ is more often apparent than the genital hook and is described and 

 figured by Wheeler. 



