Attaphila fungicola Wheeler 1900

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; exposed 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 pronotum, 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 produced, 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 moderately 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. Sinistrad within the anal chamber, a delicate, slender, elongate genital hook is produced caudad,^'''' then curving sinistrad to apex which, due to the continued curvature, 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 following 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 remaining -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. turn with these angles rectangulate, but bkintly rounded. "Posterior edges of the lamina supra-analis notched in the middle. Cerci with a very clearly circumscribed linear white spot on the dorsal surface. Subgenital plate large, nearly as long as broad, evenly rounded behind."'^*
Measurements {in millimetersY*''
Length Length Width Lengtli Width Length
j-71 of of proof proof of of cau-
body notum notum tegmen tegmen dal tibia
Austin, Texas 2.65 .945 1.65 .95 1.35 .59
Austin, Texas 2.7 1.06 1.89 .71 1.53 .59
Austin, Texas 2.7 .95 i 77 -Ji i-35 — Austin. Texas 2.45'''^'^ .945 1.9 — -55
The dorsal contour of the insect is strongly convex, the male tegmina rounding laterad, so that the costal margins are below the lateral abdominal suture. In consequence, were the pronotum and tegmina flattened out, an increase would be found for the dimensions given.
Wheeler's figures 3 and 4 are of the dorsal aspect of the insect, thus the cephalic margin of the pronotum and the costal margins of the tegmina are not visible, due to the convexity of the dorsal surface.
Coloration. — Amber yellow, sometimes suffused with sudan brown, the suffusion strongest on the limbs. Eye facets blackish brown.
Immature specimens before us of both sexes, as stated by \ heeler, resemble the female except in the smaller size and the distinctly paler coloration.
The habits of this singular roach and its unmolested presence in large numbers in the fungous gardens of the ant, Atta fervens Say, are fully discussed in the paper in which the species is described. The species is known only from the type locality.
Specimens Examined : 12; (•> mahs, i female and 5 immature individuals. Austin, Texas, II, 19, 1903, (W. M. Wheeler), 6 0^,1 ?, i ju-. cf, 2 juv. 9, 2 small juv., [A. X. S. P.. Hebard CIn. and U. S. N. M.].
3-"= The distal portion of the abdomen is, in the single female before us, drawn in and somewhat shrivelled. We conseqiientl}' quote these features from Wheeler's original description.
^■'^ Taken under the microscope.
2** Distal portion of abdomen retracted in this specimen. 2l6 NORTH AMERICAN BLATTIDAE