Atheta (Tetropla) tubericauda Bernhauer

Klimaszewski, Jan, Chandler, Donald S., Davies, Anthony & Bourdon, Caroline, 2023, Aleocharine rove beetles of New Hampshire, USA: new taxa and new records (Coleoptera, Staphylinidae, Aleocharinae), Zootaxa 5364 (1), pp. 1-141 : 42-44

71. Atheta (Tetropla) tubericauda Bernhauer , new subgeneric combination

Figs. 6a – d , Table 1

References. Bernhauer 1909.

Distribution. Nearctic. Canada: not recorded. USA: MA, NH (NSR).

This is the only record of this species from the USA besides the original record from Massachusetts (Bernhauer 1909). We have compared the NH specimen with male lectotype and they agree in external and genital morphology. The female of this species remains undescribed. The male illustrations are provided for the first time ( Figs. 6 a-d).

Collection and Habitat data. One specimen was collected from forest litter in October.

Material. USA, New Hampshire, Strafford Co.: 4 mi SE Durham, Adams Point , 11.X.1981, D.S. Chandler, berlese forest litter, 1 male .

Comments. This species is the most similar to Atheta (Tetropla) frosti Bernhauer. It is practically indistinguishable externally from A. frosti , but unlike that species male tergite VIII of A. tubericauda has three tuberculate small projections/teeth on the apical margin, two lateral and one median. In A. frosti the apical margin of male tergite VIII has two small, lateral angular projections/teeth and a sinuate margin between them (for illustration see Klimaszewski et al. 2018). The tubus of the median lobe of the aedeagus is differently shaped in the two species, being bent ventrad in A. tubericauda and bulbus bearing a narrow, spine-like frontal projection in lateral view which is missing in A. frosti . Originally A. tubericauda was described in the subgenus Atheta (s. str.), but it does not have the characteristics (larger body size, male tergite VIII without teeth, antennomeres V–X elongate or subquadrate in most, spermatheca with thin, long and irregularly twisted stem bearing small bud-shaped projections) of this subgenus. Atheta frosti (and A. tubericauda ) is also similar externally to Atheta mcalpinei Klimaszewski and Webster , described from New Brunswick and originally assigned to the subgenus Dimetrota ( Webster et al. 2016, Klimaszewski et al. 2018). It clearly shares the characteristics of the subgenus Tetropla , and is here officially transferred to this subgenus as Atheta (Tetropla) mcalpinei new combination. The differences between A. frosti and A. mcalpinei are in the shape of male tergite VIII, shape of apical part of tubus in lateral view (less curved ventrad in A. mcalpinei ), and the more transverse antennae in the latter. Additional studies are needed to examine DNA and morphological variation of the two species to establish the status of the latter species.

Figures

FIGURE 6a–d. Atheta (Tetropla) tubericauda Bernhauer: (a) habitus in dorsal view; (b) median lobe of aedeagus in lateral view; (c) male tergite VIII; (d) male sternite VIII. Scale bar for habitus = 1mm; remaining scale bars = 0.2mm.