Belongs within: Tenebrionidae.
The Palorini are an Old World group of tenebrionid beetles with a prominent subquadrate labrum, simple antennal sensilla, unlobed tarsomeres and an inverted aedeagus. Members of the widespread genus Platycotylus are strongly flattened with long antennae, reaching the base of the pronotum, and with the anterior and posterior angles of the pronotum produced and acute (Matthews & Bouchard 2008).
Characters (from Matthews & Bouchard 2008): Oblong, parallel-sided, either subcylindrical, moderately convex, or somewhat flattened, glabrous, fuscous to piceous, sometimes with partly rufous elytra. Total length 2–4 mm. Edge of clypeus more or less straight in middle to shallowly emarginate. Eyes entire, suboval or subcircular. Labrum subcircular or subquadrate, medial tormal arms of epipharynx transverse, very short and wide, their mesal extremities not extended, epitorma present or absent, setal pattern symmetrical. Mandibular mola smooth or coarsely ridged. Corpotentorium absent. Antennae usually short, compressed and cylindrical, not reaching beyond middle of prothorax, with very short first segment, segments either becoming smaller distally, gradually enlarging distally, or with five-segmented club. Mandibles apically bidentate. Maxillary palpi with apical segment ovoid or cultriform. Pronotum subquadrate or narrowing basally, disc convex, often with two lateral elongated depressions. Prosternum moderately long before coxae. Mesocoxal cavities narrowly closed by ventrites or open (closed by mesepimera). Elytra with nine striae, often obscured laterally, with or without scutellary stride, epipleura complete to apex but very narrow there, sometimes entirely narrow. Wings present, venation reduced posteriorly with second cu-a cell and AA3+4 absent, MP3+4 and CuA1 usually also absent, radial cell and r4 crossvein reduced or absent, apical membrane large, anal lobe prominent, no medial fleck. Legs not fossorial, tarsomeres subparallel and cylindrical, basal segment of pro- and mesotarsi very small, difficult to see, or absent altogether, therefore tarsal formula actually or apparently 4-4-4. Plantar surfaces sparsely setose. Abdomen with membranes visible after ventrites 3 and 4. Groove usually present along edge of apical ventrites. Defensive glands usually present, sacs small to moderate in size, exit ducts broad or a little constricted, widely separated and without common volume. Ovipositor shortened, coxites without lobation, with apical gonostyles often sclerotised and claw-like, baculi at base of coxites oblique, those of paraprocts also oblique or transverse with paraprocts rotated posterad to partially cover coxites. Female tract with vagina strongly constricted anteriorly, producing a separate sausage-shaped anterior spermatheca; accessory gland either absent or present as small globose or elongate structure attached to spermatheca; no vaginal sclerites. Bands of dense subcuticular pits seen on some ventrites internally in males. Aedeagus inverted, with very short basal piece relative to tapering apical piece which is two or three times as long, occasionally basal and apical pieces subequal, parameres separated along ventral (morphological dorsal) surface.
<==PaloriniMB08
|--UlomotypusMB08
|--Ulomina Baudi di Selve 1876 [incl. Coelopalorus Blair 1930]MB08
| `--*U. carinata Baudi di Selve 1876 [incl. *Coelopalorus foveicollis Blair 1930]MB08
|--Eutermicola Lea 1916MB08
| `--*E. sculpticollis Lea 1916MB08
|--Platycotylus Olliff 1883MB08
| |--*P. inusitatus Olliff 1883MB08
| `--P. nitidulus (Macleay 1871)MB08 (see below for synonymy)
|--Austropalorus Halstead 1967MB08
| |--*A. planatus Halstead 1967MB08
| `--A. demarzi Halstead 1967MB08
|--Pseudeba Blackburn 1903MB08
| |--*P. novica Blackburn 1903 [incl. Palorus eutermiphilus Lea 1921]MB08
| |--P. fossor Halstead 1967MB08
| |--P. puncticollis Halstead 1967MB08
| `--P. watsoni Britton 1973MB08
`--Palorus Mulsant 1854 (see below for synonymy)AT02
|--*P. depressus (Fabricius 1790) [=Hypophloeus depressus]MB08
|--P. austrinus Champion 1896MB08
|--P. cerylonoides (Pascoe 1864) [=Eba cerylonoides]MB08
|--P. grossi Halstead 1967MB08
|--P. intermedius Halstead 1967MB08
|--P. laxipunctus Fauvel 1904 [incl. Acthosus pygmaeus Carter 1914]MB08
|--P. neboissi Halstead 1967MB08
|--P. ratzeburgi (Wissmann 1848) [=Hypophloeus ratzeburgi]MB08
|--P. reticulatus Halstead 1967MB08
|--P. subdepressus (Wollaston 1864) [=Hypophloeus subdepressus]MB08
`--P. upoluensis Blair 1928MB08
Palorus Mulsant 1854 [incl. Caenocorse Thomson 1859, Circornus Fleischer 1900, Eba Pascoe 1863, Platyotus Gerstaecker 1871]AT02
Platycotylus nitidulus (Macleay 1871)MB08 [=Ipsaphes nitidulusMB08, Sitophagus nitidulusM86; incl. Platycotylus coloratus Blackburn 1903MB08]
*Type species of generic name indicated
References
[AT02] Aalbu, R. L., C. A. Triplehorn, J. M. Campbell, K. W. Brown, R. E. Somerby & D. B. Thomas. 2002. Tenebrionidae Latreille 1802. In: Arnett, R. H., Jr, M. C. Thomas, P. E. Skelley & J. H. Frank (eds) American Beetles vol. 2. Polyphaga: Scarabaeoidea through Curculionoidea pp. 463–509. CRC Press.
[M86] Masters, G. 1886. Catalogue of the described Coleoptera of Australia. Part IV. Proceedings of the Linnean Society of New South Wales, series 2, 1 (2): 259–380.
[MB08] Matthews, E. G., & P. Bouchard. 2008. Tenebrionid Beetles of Australia: Descriptions of tribes, keys to genera, catalogue of species. Australian Biological Resources Study: Canberra.