Limonius lecontei Lane, 1971

Etzler, Frank E., 2018, A New Species of Limonius Eschscholtz, 1829 (Coleoptera: Elateridae: Dendrometrinae) from Montana, with a Correction of the Application of Limonius consimilis Walker, 1866, The Coleopterists Bulletin 72 (4), pp. 861-865 : 862-865

Limonius lecontei Lane, 1971

Limonius nitidicollis LeConte 1869: 378 (not Limonius nitidicollis Laporte 1840: 242 ).

Limonius consimilis auct ., not Walker 1866. Horn 1875: 168; Al Dhafer 2009: 273 (and references within). Returned to synonymy following Lane (1971).

Pheletes consimilis: Leng 1920: 168 .

Limonius lecontei Lane 1971: 24 (replacement name for L. nitidicollis LeConte ).

The L. consimilis species-group, to which I add the new species as the fifth member of the group, can be diagnosed by the following set of characters: prosternal sutures grooved and excavated anteriorly; unicolorous elytra; length 8 mm or less; pronotum as wide as long; and antennae usually just reaching the posterior edge of the pronotum (male) or not reaching the posterior edge (female). Exceptions to the antennal length character are found in L. jonesi , where the antennae exceed the posterior pronotal edge by up to the length of a single antennomere, and in some specimens of the new species in which the antennae exceed the posterior pronotal edge by half an antennomere. The male aedeagi of all species in this group possess parameres that are relatively wider than other Limonius species (e.g., Figs. 3–6 ).

Limonius seibertae Etzler , new species ( Figs. 1–5 ) Zoobank.org/ urn:lsid:zoobank.org:act:21266B8F-4C79-4816-9C52-FDBE51F42FAA

Diagnosis. Limonius seibertae can be distinguished from other species in the L. consimilis species-group by the combination of sinuate frontal margin ( Fig. 1 , inset), dark brown elytra that slightly contrast with the pronotum, the presence of a strong carina on the pronotal hind angle, pronotal punctation on disc that is small, not clearly subumbilicate, separated by one puncture diameter or more, and the wide, laterally subparallel parameres of the aedeagus ( Fig. 5 ). Specimens of L. seibertae may be confused with L. consimilis in collections, but the latter species possesses a broadly curved frontal margin ( Fig. 2 , inset), piceous elytra that do not contrast with the pronotum, and parameres more sinuate laterally ( Fig. 6 ), allowing for easy separation on close examination. Another species that has potential for mix up is L. jonesi , but the lack of a carina on the hind angles and dense, umbilicate punctures on the pronotal disc (almost giving a rough, sponge-like appearance) will readily separate this species from L. seibertae .

Description. Length 7.0– 7.8 mm, width (measured at elytral base) 1.8–2.2 mm. Body elongate; head and pronotum piceous to black dorsally; body dark brown to piceous ventrally, with edges of hypomeron, coxae, posterior edges of abdominal segments, and edges of legs lighter; elytra dark brown to brown, noticeably lighter than pronotum under microscope. Pubescence short, gray; setae on pronotal disc directed medially, with medial line of setae directed anteriorly ( Fig. 1 ). Head: Frontal carina straight, not sinuate when viewed anteriorly, sinuate when viewed dorsally ( Fig. 1 , inset). Frontal carina distinctly elevated from clypeal base. Antenna reaching hind angle of pronotum or extending beyond by half an antennomere; antennomeres gradually becoming narrower distad; antennomeres 2 and 3 subcylindrical, rather shiny; 3 slightly longer than 2, slightly shorter than 4; 4 slightly longer than wide (nearly quadrate in some specimens); 4–10 serrate; 4–11 densely punctate, dull, with edges subtly more setose; 11 oval. Pronotum: As wide as long; sides nearly subparallel, converging slightly anteriorly; anterior angle curved medially; punctures umbilicate, less distinctly so on disc, separated by ~1 puncture diameter on disc and closer and distinctly umbilicate toward edges; interspaces smooth, shiny; hind angles not divergent, each with a strong, raised carina, not strongly diverging from lateral carina ( Fig. 1 , white arrow). Scutellum: Broadly rounded posteriorly; with dense granulate punctures. Elytra: Together same width as distance between apices of hind angles of pronotum; sides subparallel in basal 2/3, then narrowed to rounded apex; striae slightly impressed, punctures connected longitudinally with shallow groove; intervals nearly flat, shiny, with punctures nearly as large as those in striae. Venter: Prosternal punctures very close and subumbilicate anteriorly and laterally, less close and less clearly subumbilicate medially; prosternal process with dense, subumbilicate punctation, giving rough appearance; prosternal suture distinctly excavated anteriorly. Hypomeron with close, subumbilicate punctures, separated by less than 1 puncture diameter; some specimens with small impunctate area at base near groove (for reception of profemur), others with punctures less dense in this area. Mesocoxal cavity with mesepimeron and mesanepisternum forming part of mesocoxal cavity; mesanepisternum reaching cavity by narrow protuberance. Metasternum with punctures close, separated by less than 1 puncture diameter, shallow and nearly subumbilicate anteriorly and laterally, deeper and appearing simple medially and posteriorly, much smaller and finer than punctures on prosternum. Abdomen with punctures finer and simple; lateral carina of each ventrite with microserrations. Male genitalia: Measuring less than 1 mm. Median lobe extending slightly beyond apical ends of parameres ( Fig. 5 ); subequal in width to parameres; subparallel throughout, then narrowing at nearly cylindrical apex; basal struts short and divergent. Parameres broad; sides subparallel towards apex; apices broadly rounded, membranous, bearing 1 prominent seta; with prominent subapical tooth; ventral face mostly open, exposing most of median lobe; basal piece subquadrate and membranous area semicircular.

Type Material. Holotype: K-27; 1 ½ mi. S., 5 W. Winnett ; Petroleum Co., Montana; 5-24-1971 / N. E. Rees; Collector / CO 253 (from MTEC, on permanent loan to CASC [California Academy of Sciences , San Francisco, CA, USA]) . Paratypes (12): W-3; 3mi N.W. Winnett; Petroleum Co., Montana; 5-24-1971 / N. E. Rees; Collector / CO 253 (2 MTEC) . W-4; 3mi N.W. Winnett; Petroleum Co., Montana; 5-24- 1971 / N. E. Rees; Collector / CO 253 (1 MTEC, 1 CASC) . W-7; 3mi N.W. Winnett; Petroleum Co., Montana; 5-24-1971 / N. E. Rees; Collector / CO 253 (2 MTEC) . W-10; 3mi N.W. Winnett; Petroleum Co., Montana; 5-24-1971 / N. E. Rees; Collector / CO 253 (1 CASC, 1 MTEC) . W-11; 3mi N.W. Winnett; Petroleum Co., Montana; 5-24-1971 / N. E. Rees; Collector / CO 253 (1 CASC) . K-4; 1 ½ mi. S., 5 W. Winnett ; Petroleum Co., Montana; 5-24-1971 / N. E.Rees; Collector / CO 253 (1 MTEC) . K-5; 1 ½ mi. S., 5 W. Winnett ; Petroleum Co., Montana; 5-24-1971 / N. E. Rees; Collector / CO 253 (1 MTEC) . K-24; 1 ½ mi. S., 5 W. Winnett ; Petroleum Co., Montana; 5-24-1971 / N.E. Rees; Collector / CO 253 (1 MTEC) .

Discussion. Limonius seibertae is only known from two localities in Petroleum Co., Montana and a single collecting date. All specimens were collected as by-catch from a survey on grasshopper abundance ( Hewitt and Rees 1974). Specimens with ‘W’ s are from Winnett transects, while specimens with ‘K’ s are from King transects ( Hewitt and Rees 1974). The following 12 plant species were recorded from both transects: western wheatgrass ( Pascopyrum smithii (Rydb.) Á. Löve , Poaceae ), bluebunch wheatgrass ( Pseudoroegneria spicata (Pursh) Á. Löve ssp. Spicata, Poaceae ), prairie junegrass ( Koeleria macrantha (Ledeb.) Schult. , Poaceae ), needleandthread ( Hesperostipa comata (Trin. & Rupr.) Barkworth , Poaceae ), green needlegrass ( Nassella viridula (Trin.) Barkworth , Poaceae ), blue grama ( Bouteloua gracilis (Willd. ex Kunth) Lag. ex Griffiths , Poaceae ), sandberg bluegrass ( Poa secunda J. Presl. , Poaceae ), needleleaf sedge ( Carex eleocharis C. A. Mey. , Cyperaceae ), moss phlox ( Phlox hoodii Richardson , Polemoniaceae ), American vetch ( Vicia americana Muhl. ex Willd. , Fabaceae ), fringed sagewort ( Artemisia frigida Willd. , Asteraceae ), and big sagebrush ( Artemisia tridentata Nutt. ) (Hewett and Rees 1974, table 2, with updated taxonomy).

Limonius seibertae likely has a broader range than is presented here, and the plant species listed above may help predict its total range. Specimens of L. consimilis reported from Saskatchewan, Canada ( Bousquet et al. 2013) are likely candidates for L. seibertae and deserve a second look. Extreme caution should be used when using the current literature to interpret the ranges of L. consimilis and L. lecontei , as specimens are often confused.

Identifying species in the L. consimilis speciesgroup will be difficult using the key provided by Al Dhafer (2009). Limonius seibertae will run to couplet 33 (other species in this group will go to couplet 35), which leads to Limonius pectoralis LeConte, 1866 and Limonius cribriceps Van Dyke, 1943 . Limonius seibertae can be distinguished from L. pectoralis by the all-black pronotum, the wide parameres of the aedeagus, and the sparser punctation on the metasternum. From L. cribriceps , L. seibertae can be distinguished by lacking an emarginate posterior hypomeral margin, the wide parameres of the male genitalia, and its presently known distribution.

To ensure accurate identification of the species noted here, I provide a revised key for the species-group.

Figures

Figs. 3–6. Aedeagi of western species in the Limonius consimilis species-group, ventral view. 3) L. pappi, redrawn from fig. 1 in Becker (1976); 4) L. jonesi, redrawn from fig. 2 in Becker (1976); 5) L. seibertae, holotype; 6) L. consimilis, Flathead Co., Montana. Scale bar = 0.5 mm, all at same scale.

Figs. 1–2. Limonius species, dorsal habitus. 1) L. seibertae, holotype. White arrow points to carina of pronotal hind angle. Inset: Sinuate frontal carina, dorsal view; 2) L. consimilis, Chelan Co., Washington. Inset: Broadly rounded frontal carina, dorsal view. Scale bars = 5 mm.