50 THE BLATTIDAE OF PANAMA 



Specialized ; subgenital plate and concealed genitalia complex and 

 asymmetrical. 



Ventro-cephalic margin of cephalic femora armed with a series of 

 heavy spines, the distal spines much the shorter and the more closely 

 placed, terminating in two heavy and very elongate distal spines 

 in increasing ratio. '^^ Ventro-caudal margin of cephalic femora 

 armed throughout its length with well-spaced heavy spines (four 

 and one distal). Other ventral femoral margins well supplied with 

 heavy elongate spines. Ventral surface of four proximal tarsal 

 joints supplied distad with small pulvilli, the apices of which are 

 sharply rounded. Tarsal claws unspecialized, but with a weak 

 indication of an internal flange. Well developed arolia present. 

 Rhytidometopum megalopteruna new species (Plate III, figures 8 and 9.) 



The present insect entirely lacks distinctive markings. The 

 brown of the pronotal disk and tegmina is unusually lustrous and 

 rich in tone. 



Type. — d"; Trinidad River, Panama. June 3, 1912. (A. Busck.) 

 [United States National Museum.] 



In addition to the generic features already given, we would note the following for 

 the present species. Interocular space two-fifths that between the antennal sockets, 

 very feebly ridged, which ridge shows a number of weak longitudinal creases. 

 Ocellar spots distinct, their areas showing no delimiting contour. Third joint of 

 maxillary palpi slightly longer than fourth, fifth (distal) joint enlarged and in length 

 intermediate between these. Tegmina with numerous discoidal sectors (eight to 

 thirteen in the series, variability due to branching). Wings with (in the series four 

 to six) complete branches of the ulnar vein; intercalated triangle conspicuous, neariy 

 as wide as deep. Sixth dorsal abdominal segment weakly depressed mesad, the 

 depression containing a tuft of agglutinated hairs, seventh and eighth dorsal seg- 

 ments transversely narrower, exposed only very narrowly along their caudal margins. 



Supra-anal plate strongly transverse, basal width six times length, distal margin 

 convex between the cerci with an angulation feebly indicated. Cerci small and 

 slender, tapering to acute apex, the joints (twelve) strongly defined, the lateral 

 margin of each convex, particularly distad ; dorsal surface only slightly less convex 

 than ventral surface. Paired plate beneath supra-anal plate of male large and 

 unspecialized. Titillator with apex straight, aciculate, directed caudad. 



Subgenital plate strongly asymmetrical and irregular; free margin roughly con- 

 vex, excepting sinistrad where it is broadly and shallowly concave and recurved, to 



88 Occasionally the last spine of the series preceding these is appreciably longer than 

 those before it, thus showing a partial transition toward the forms having tiiree heavy 

 and elongate distal spines. 



