Lathrobium (Lathrobioma) nanulum (Casey, 1905)

Haberski, Adam & Caterino, Michael S., 2024, A review of Nearctic Lathrobium (Coleoptera, Staphylinidae), with revision and descriptions of new flightless species from the mountains of the southeastern U. S., ZooKeys 1198, pp. 193-277 : 193

Lathrobium (Lathrobioma) nanulum (Casey, 1905)

Lathrobioma nanula Casey, 1905: 100.

Lathrobium (Lathrobioma) nanulum : Bernhauer and Schubert 1912: 264.

Type material.

Lectotype, Lathrobioma nanula Casey, herein designated (USNM): "MASS / CASEY bequest 1925 / [red] TYPE USNM 38139 / [handwritten] Lathrobioma nanula / Lectotype Lathrobioma nanula Casey Desg. Haberski & Caterino."

Other material.

Same data as lectotype (1, USNM).

Diagnosis.

Lathrobium nanulum can be distinguished from other Lathrobioma by unique genitalic characters. The ventral process of the aedeagus is narrow instead of broad. Female sternum IX with valvifers and coxites fully divided instead of fused.

Description.

Small species, body length 5 mm; body and appendages dark red coloration. Gular sutures arcuate; antennomeres V-VII wider than long; maxillary palpomere III more than 0.4 × as wide as long. Elytra 1.2 × longer than pronotum. Females with paraprocts undivided, apices shorter than basal portion; sternite VIII oblong. Dorsal plate and ventral process of aedeagus with large apical teeth (Fig. 30 ).

Distribution.

USA: MA.

Remarks.

Blackwelder (1939), in his revision of the paederine genera, placed L. nanulum in the subgenus Lathrobium Deratopeus , now a synonym of the genus Tetartopeus , without providing any explanation. We transfer it back to Lathrobioma , because it lacks any of the defining characters of Tetartopeus , such as a narrow neck, but does share the subgeneric synapomorphies of Lathrobioma listed above for L. divisum .

Figures

Figures 29 - 34. Lathrobium terminalia A female terminalia B male sternite VIII C aedeagus in ventral view D Aedeagus in lateral view. 29 L. divisum 30 L. nanulum 31 L. othioides 32 L. scolopaceum 33 L. tenue 34 L. amplipenne. Scale bars: 1 mm.