Tympallopatrum Perkins 1997

Perkins, Philip D., 2004, A revision of the Western Australian endemic humicolous beetle genus Tympallopatrum Perkins (Coleoptera: Hydraenidae), Zootaxa 672, pp. 1-16 : 3

Tympallopatrum Perkins 1997

Tympallopatrum Perkins 1997: 145 (type species Tympallopatrum longitudum Perkins, 1997 ).

Diagnosis. Recognized among Ochthebiinae by the transversely convex body form and very setose dorsum with carinae and/or callosities, the prominent ocelli located near the eyes, the basomedial tumidity of the frons behind which are three longitudinal carinae, the lack of a lateral hyaline border of the pronotum, the shape of the mentum, the gular ridge, the median metasternal impression, eight articled antenna (three + club) having the second article apically cupuliform, and features of the antennal pocket.

Description. Form transversely convex, body size ca. 1.50–1.80 mm. Dorsal reliefs strongly setose, including frons tumidity, ocelli, four longitudinal sinuate costae on pronotum, and four costae on elytra (on even numbered interseries), costae often interrupted or replaced by callosities. Ocelli prominent, located next to eyes. Frontoclypeal suture deep, angulate. Frons with basomedial tumidity, separated from ocelli by longitudinal sulcus; lateral margin angulate or with minute point; three strong parallel longitudinal carinae behind tumidity. Antennomeres 8 (three + club); second cupuliform, third very small, not cupuliform. Maxillary palpi short, ochthebiine. Labrum deflexed. Mentum longer than wide. Gula with a prominent transverse ridge. Pronotum with disc transversely convex, bearing four sinuate setose costae; anterior and posterior hyaline borders narrow, bearing tiny cuticular processes; lateral margins arcuate, denticulate and setose, lacking hyaline border, sometimes minutely excavate near posterior angles. Elytra with ten series of punctures, sometimes series very irregular and interrupted; suture and even numbered interseries at least in part costate and setose. Prosternum narrow in front of procoxae, with low midlongitudinal carina or very weak indistinct ridge. Hypomeron with carina forming margin of antennal pocket. Metasternal disc dull or shining, with median longitudinal or oval impression. Intercoxal sternite small, triangular. Legs short, tarsi very short, fivefive­five. Hydrofuge pubescence present on postocular area, bubble­hypomeron, notal postcoxal projection, mesosternum, narrow band around shining metasternal area, first abdominal sternite, and narrow lateral band of abdominal sternites two to five.

Antennal pocket (terminology as in Perkins, 1997) hypomeral, wide, medial 0.5–0.8 hydrofuge pubescent (asperite type), lateral nonpubescent part weakly microreticulate; lateral margin of antennal pocket forming ridge, free edge not extending to form hh­border; ridge continuous with ah­border, not continuous with the ph­border. Wet­hypomeron quite small, with setose tuberculate enlargements. Antennal cleaner of prosternum well developed. Profemur with large spines over most of upper surface, spines not organized to form distal spine cluster. Postocular area with distinctive trans­genal ridge adjacent to posteroventral angle of eye; postocular hydrofuge moderately dense, of asperite type; genal pubescence sparse, nonasperite, and with few exocrine pores; periocular pores present.