PROC. ENT. SOC. WASH., VOL. 67, NO. 4, DECEMBER, 1965 255 THE SYSTEMATIC POSITION OF THE PSAMMINAE (Heteroptera: Lygaeidae)"^ James A. Slater" and Merrill H. Sweet* Bergroth ( 1921 ) erected the tribe Psammini to include two mono-typic genera, Psammitim Breddin from South Africa and Sympeplus Bergroth from India. The tribe was placed by Bergroth in the lygaeid subfamily Geocorinae chiefly because of the large protruding "reni-form" eyes possessed by members of this latter subfamily. We have recently had occasion to examine members of both genera of Psammini and find that they do not belong to the Geocorinae and cannot be placed within any existing subfamily of Lygaeidae on the basis of our present subfamilial concepts. In this paper we review the relationships of these curious insects in an attempt to ascertain their systematic position and conclude that they are lygaeids rather than members of related "lygaeoid" families, and that they should consti-tute a distinct subfamily. Both Psammium and Sympeplus are very small insects, not exceed-ing 2V-2 mm. in length. The mesothoracic wings are highly modified into a complete "coleopteroid" shell which lacks a membrane, has the clavus and corium indistinguishably fused, completely covers the abdomen, is strongly convex and meets in a straight line down the middle of the dorsum. The hind wings are lacking. The body is nearly uniformly coarsely punctate, the eyes large and reniform, the antennae short and subclavate, the legs short and rugose but not distinctly fossorial. It seems evident that both genera are adapted for some type of cryptic habitat, although nothing is known of their biologies. The systematic position of these insects is very difficult to ascertain for not only do they have a number of features which appear to be of phylogenetic significance, but they also present a number of other characters which may be better interpreted as reduction phenomena. Some of these modifications may be associated with the wing modifi-cations for a specialized habitat. We propose in the following discussion to comf)are the Psamminae to allied families of Lygaeoidea and then to subfamilies of the family Lygaeidae itself. a. Family Position: Both Psammitim and Sympeplus possess dorsally located spiracles on all abdominal segments nonnally bearing these structures which ^ This work was supported by grants from the National Science Foundation and the University of Connecticut Research Foundation. -Department of Zoology and Entomology, University of Connecticut, Storrs, Connecticut. ^ Department of Biology, Texas A & M University, College Station, Texas.
BioStor
