A NEW FLIGHTLESS PSAMMODIUS FROM FLORIDA'S INLAND DUNES (COLEOPTERA: SCARABAEIDAE)
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ABSTRACr Psammodius relictillus is described from specimens taken from relict inland dunes in Florida. This blind and flightless species occurs in Florida scrub habitat on the southern Lake Wales Ridge and on the highly disjunct Atlantic Coastal Ridge. It lives in deep, well-drained sand, apparently aggregating around buried, dead, plant material, such as the buried middens of the harvester ant, Pogonomyrmex badius. The genus Psammodius Fallen is worldwide in distribution, with 35 species described from the Western Hemisphere, including 16 from the United States (Woodruff 1973). The New World species were revised by Cartwright in 1955. The genus may be due for a new revision; not only does it appear that there are undescribed species, but a reconstruction of the phylogeny of the species has not been seriously attempted. Pending the advent of a coleopterist willing to assume this ambitious task, we are describing a distinctive Florida species, so that a name will be available for projects dealing with the biogeography and conservation of arthropods found in Florida scrub habitats. The genus Psammodius cannot presently be defined by a set of diagnostic characters, as the species in the genus are morphologically diverse, and some species are at least superficially similar to species of Pleurophorus and Ataenius. The latter genus is not even placed in the tribe Psammodiini, an indication of the amount of phylogenetic work still needed in this area of the Scarabaeidae. The following diagnosis of Psammodius is taken from Woodruff (1973). We cannot say which character states represent synapomorphies. DiAGNosIs. Small (length 2.0-4.6 mm), convex, shining, reddish-brown to dark brown. Head granulate, granules rarely elongate transversely; clypeus emarginate at middle, angle on each side may be dentate. Eyes usually hidden when head is in repose, a deep depression (anteocular pit) in front of eye along lateral margin of gena. Pronotum convex; punctures scattered, often large and deeply impressed, sometimes forming transverse furrows or depressions accompanied by swollen impunctate areas; at least part of lateral and posterior margin fimbriate, setae not clavate. Elytra often swollen posteriorly, striae moderately impressed and intervals convex. Middle and posterior tibiae each noticeably widened at apex, spurs often flattened, spatulate and longer than