Trichonychini Reitter, 1882

Owens, Brittany E. & Carlton, Christopher E., 2016, Collecting in the Museum: New Species, Taxonomic Changes, and Range Extensions of Euplectite Pselaphinae (Coleoptera: Staphylinidae) of the Southeastern United States, The Coleopterists Bulletin 70 (3), pp. 611-633 : 611-633

Tribe Trichonychini Reitter Subtribe Panaphantina Jeannel Bibloplectus Reitter, 1881

Diagnosis. Males. Head: Rounded trapezoidal, tempora slightly rounded behind ocular canthus, vertexal foveae obvious, frontal sulcus broad, shallow between foveae; antennal acetabula remote, antennomere 2 rounded, wider than first, antennomeres 3–8 unmodified, antennomeres 9–11 forming loose club; labrum of normal form for tribe, bearing pair of sensory pegs, mandibles broadly sickle-shaped, maxillae and labium typical for subfamily, labial palpi minute, 2-segmented, maxillary palpi unmodified, palpomere 1 minute and obliquely joined to palpomere 2, palpomere 2 pedunculate, narrower in basal 1/3, slightly expanded and rounded distally, palpomere 3 subtriangular, palpomere 4 widest, unmodified, bearing apical palpal cone; gula simple, slightly rounded anteriorly, paired gular fovea present; eyes well-developed, comprised of about 20 facets each. Thorax: Pronotum rounded trapezoidal, disc evenly convex, antebasal transverse sulcus bisected by short, basal carina, margin delimited by lateral antebasal fovea, longitudinal median sulcus absent, lateral antebasal fovea present, prosternum convex, median procoxal fovea present, lateral procoxal foveae present; mesoventrite bearing paired lateral mesoventral and mesocoxal fovea, mesocoxae contiguous; lateral metaventral foveae present, metacoxae conjunct; legs variously modified; elytra with sutural fovea and striae, 2 basal discal foveae present, subhumeral foveae present, lateroapical cleft present, wings present or absent. Abdomen: Tergite II with small basolateral foveae, mediobasal foveae delimiting median sulcus; tergite III with small basolateral foveae, mediobasal foveae delimiting median impression; tergite IV with small basolateral foveae; ventrite II with large basolateral foveae and setose lateral sulci; ventrites III–IV with small basolateral foveae, variously modified; ventrite VII ovate, hinged penial plate. Genitalia: Strongly asymmetrical; composed of basal bulb with ventral strut; parameres asymmetrical; accessory processes often extensively modified.

Females. Similar to males except eyes usually smaller, composed of fewer facets, and secondary sexual modifications of the legs absent (redescription, Chandler 1990).

Notes. The genus Bibloplectus includes some of the smallest members of the subfamily Pselaphinae (most species 0.6–0.9 mm long). This small body size in conjunction with the absence of externally visible distinguishing characters on males, with the exception of some characters on the legs, has complicated the identification of species.

Worldwide, this genus contains more than 40 species from North America and the Old World. Previous to the last revision by Chandler (1990), four US species were described. Two of these, Bibloplectus integer (LeConte, 1878) and Bibloplectus sobrinus Casey, 1897 , occur from Manitoba to Nova Scotia and Connecticut to Rhode Island, respectively. The addition of five species by Chandler (1990) brought the number of Bibloplectus species in the southeastern USA to seven. The majority of US species in the genus are known from only a handful of localities, with a particular concentration of diversity in eastern Oklahoma due to the collecting efforts of Karl Stephan (1921–2005) ( Carlton et al. 2005), while Bibloplectus leviceps ( Casey, 1884) , and Bibloplectus ruficeps Motschulsky, 1856 are known from farther south and east to Louisiana, Alabama, Florida, Georgia, and Virginia.

Five new species of Bibloplectus are here described from specimens located in the LSAM. Four are described from type localities in the southeast United States (two from Alabama and one from Arkansas), and a fifth is described from Pennsylvania. We include an updated checklist and key to all North American species, including those known from northern localities .

KEY TO MALES OF THE NORTH AMERICAN SPECIES OF BIBLOPLECTUS REITTER (Modified from Chandler 1990)

1. Mesotrochanters with ventral quadrate flange, metatibiae markedly swollen and setate at middle................... B. ruficeps Motschulsky

1′. Mesotrochanters lacking modifications, metatibiae evenly swollen in apical half............... 2

2. Mesotibiae with small apical or subapical tooth on posterior margin, often difficult to see in pubescence...................................... 3

2′. Mesotibiae with large tooth at posterior apex, easily seen......................................................5

3. Mesotibiae swollen medially, tooth subapical; aedeagus with diaphragm near middle...........4

3′. Mesotibiae not swollen medially, tooth apical; aedeagus with diaphragm at base ............ ............................... B. choctaw Chandler

4. Meso- and metatibiae lightly setate at apex; aedeagus broad apically with several processes................... B. cherokee Chandler

4′. Meso- and metatibiae densely setate at apex; aedeagus evenly narrowed to apical point................................. B. creek Chandler

5. Metatibiae with apical flange present ......... 6

5′. Metatibiae lacking apical flange.................. 9

6. Mesotibiae with small apical flange and terminal spine ( Fig. 3c )............ B. bossartae Owens and Carlton , new species

6′. Mesotibiae with elongate apical flange not associated with terminal spine...................7

7. Ventral lobe only reaching to apical fourth of aedeagus; known from the southeastern USA................................. B. leviceps Casey

7′. Ventral lobe extending past apex of median lobe; known from the northeastern United States..........................................................8

8. Strongly recurved tooth at apex of aedeagus; lacking long forked penile extension; known from Nova Scotia to Manitoba ............... B. integer (LeConte)

8′. Tooth at aedeagal apex not strongly recurved; long forked penile extension present; known from Connecticut to Rhode Island ............................. B. sobrinus Casey

9. Metatibiae with terminal row of thick spines ( Fig. 7d )....... B. ferroi Owens and Carlton , new species

9′. Metatibiae with row of thickened setae or not............................................................10

10. Mesotibiae with elongate flange, lacking associated terminal spine.........................11

10′. Mesotibiae with shortened flange and associated spine..............................................12

11. Ventral lobe of aedeagus with accessory sickleshaped paramere ........... B. osage Chandler

11′. Ventral lobe of aedeagus with broadly lobed accessory structure bearing subapical long, acute tubercle ......... B. chickasaw Chandler

12. Aedeagus with ventral lobe short, about 1/2 length of median lobe ( Fig. 4a, b ) ................. ......... B. faulknerensis Owens and Carlton , new species

12′. Aedeagus with ventral lobe reaching or exceeding length of median lobe.............13

13. Aedeagus with ventral lobe dorsoventrally flattened and expanded laterally ( Fig. 2a, b )............. B. baylessae Owens and Carlton , new species

13′. Aedeagus with ventral lobe greatly elongate and bent at right angle dorsally at 2/3 length ( Fig. 8a, b ) ....... B. kylei Owens and Carlton , new species

Figures

Figs. 2–4. Bibloplectus species. 2) B. baylessae - a) Aedeagus, lateral view, b) Aedeagus, dorsal view, c) Mesotibia, d) Metatibia; 3) B. bossartae - a) Aedeagus, lateral view, b) Aedeagus, dorsal view, c) Mesotibia, d) Metatibia; 4) B. faulknerensis - a) Aedeagus, lateral view, b) Aedeagus, dorsal view, c) Mesotibia, d) Metatibia.

Figs. 5–8. Bibloplectus species. 5) B. ferroi, dorsal habitus; 6) B. ferroi, lateral habitus; 7) B. ferroi - a) Aedeagus, lateral view, b) Aedeagus, dorsal view, c) Mesotibia, d) Metatibia; 8) B. kylei - a) Aedeagus, dorsal view, b) Aedeagus, lateral view, c) Mesotibia, d) Metatibia.