Paradonus gallatinensis, Etzler Usa, 2020

Etzler Usa, Frank E., 2020, Review of the genus Paradonus Stibick, 1971 (Elateridae: Negastriinae), with three new North American species, Zootaxa 4750 (4), pp. 524-544 : 538-540

7. Paradonus gallatinensis new species

Figs. 15, 19.

Diagnosis: This species will most likely be confused with Paradonus gustafsoni (see below) with which it shares a similar range. It can be distinguished by being unicolorous brown or piceous (compared to an apical testaceous spot on elytra and testaceous pronotal disc in P. gustafsoni ), the generally smaller size (2.45–3.1mm), and, in males, the narrower medial lobe of the aedeagus. When compared side by side, P. gallatinensis has a relatively narrower pronotum. In the Pacific Northwest and Montana, this species may also be confused with unicolorous individuals of P. pectoralis , but the pronotal hind angle carina reaching the apex will distinguish P. gallatinensis and the aedeagus with parameres lacking apical expansions.

Description: Length 2.45–3.1mm (avg. 2.8mm, n=25), color brown to dark brown, generally unicolorous dorsally, sometimes lighter areas on humeral angles and apex of elytra, body moderately dorso-ventrally flattened, evenly covered in short, appressed grey setae. Habitus Fig. 15.

Head: brown to dark brown; punctures subumbilicate, dense, separated by a diameter or less, some specimens with punctation almost contiguous in spots, slightly smaller than punctures on pronotum, surface relatively dull to moderately shining and microreticulate; antennae feebly serrate, antennae usually mostly brown, often light brown; scape sometimes dark brown, matching head, with apex brown, other antennomeres brown, usually lighter apically, most noticeable on antennomeres 8-11, rarely all dark brown,11 th segment with indention on dorsal side only.

Thorax: Pronotum brown to dark brown dorsally, nearly piceous in some, with anterior and posterior edges often subtly lighter. Pronotum wider than long, (avg. ratio: 1:1.23; n=26), widest at midlength; sides broadly arcuate, evenly curved anteriorly and posteriorly; hind angles sinuate laterally, acute tip pointing laterally and slightly dorsally in lateral view, carina strong, straight to subtly arcuate, connecting only to apex of hind angle, reaching bulbous area of pronotum; punctures umbilicate, dense, separated by a diameter or less, interspaces relatively dull and microreticulate. Hypomeron usually testaceous to light brown, rarely dark brown, punctures umbilicate, dense, almost contiguous anteriorly, gradually becoming less so to impunctate area on posterior one-fourth, interspaces relatively dull and microreticulate. Prosternum testaceous, rarely dark brown, punctures umbilicate, separated by a diameter or less, more distant medially, interspaces shining and feebly microreticulate. Metaventrite light brown to brown, punctures simple to subumbilicate, dense, separated by a diameter or less, closer posteriorly and laterally, smaller than prosternum, interspaces moderately shining and microreticulate or shining and feebly microreticulate. Scutellum subpentagonal, flat, moderately elongate, wider than long, slightly inclined, anterior edge slightly curved, surface indistinctly but rugosely punctured, brown medially, piceous along edges. Elytra brown, mostly unicolorous, uncommonly a vague dark patch medially near apical one-third, punctures simple, regularly spaced, separated by one to two diameters in most cases, sometimes closer, interspaces relatively dull and microretculate to moderately shining and feebly microreticulate. Legs light brown to brown, often subtly lighter at apical ends of each segment, usually not strongly contrasting metaventrite and abdomen, some specimens with uniform light brown legs, contrasting body.

Abdomen: Light brown to brown, darker specimens often subtly lighter along edges and fifth ventrite, and darker along lateral edges in lighter specimens; Punctures minute, very dense, almost contiguous in spots, interspaces moderately shining and feebly microreticulate.

Male Genitalia (Fig. 19): Parameres without apical expansion of dorsal condylite, dorsal condylite around 0.48x total paramere length. Median lobe narrow, extending past parameres by around 0.21x of total aedeagal length. Basal piece quadrate, convex, around 0.18x of total aedeagal length.

Specimens Examined: 110 specimens: Holotype: Gallatin Co., Bridger Cr. 4800’, pitfall trap, 26 Apr—10 May 1987, D. L. Gustanfson col., male, deposited in CASC.

Paratypes: USA: Colorado: Grand Co., Willow Crk abv. Granby, July 10, 1989, S. Wells (3, BWPC); Jackson Co., Illinois R. at Rand, July 10, 1989, S. Wells (13, BWPC); Larimer Co. , Cache La Poudre R., Fort Collins , Mar. 24, 1995, Wells-Kondratieff (1, BWPC); Montezuma Co. , Mancos River , May 7, 1999, Opler-Wells (4, BWPC) .

Montana: Broadwater Co., Missouri R-Townsend, 28 June 1989, D. L. Gustafson col (1, MTEC); Flathead Co., Glacier National Park, N. Fork Flathead area, 26 Aug 1991, K. B. Miller Colr./ Flathead R.,. 5mi S. Quartz Creek, 3420’, 26 Aug 1991 / stream-side washing (1, MTEC); Gallatin Co., Bridger Cr. 4800’, pitfall trap, 01-14 Apr 1987, D. L. Gustanfson col (2, MTEC); as previous but dates 14-26 Apr 1987 (3, ANSP; 3, INHS; 3, CASC; 1, CESC; 4, MTEC); as previous but dates 26 Apr—10 May 1987 (5, CASC; 1, CESC; 2, ANSP; 2, INHS; 5, MTEC); as previous but dates 19 May—7 June 1987 (2, CASC; 3, MTEC); as previous but dates 7-20 June 1987 (2, CASC; 2, MTEC); as previous but dates 20-30 June 1987 (3, CASC; 1, CESC; 3, MTEC); as previous but dates 1-28 July 1987 (1, MTEC), as previous but date July 1987 (1, MTEC); Gallatin Co., Bozeman UV light, 25 Jul 1987, D. L. Gustafson col. (1, MTEC); Gallatin Co., Gallatin R. 4700’, 12 Mar 1987, D. L. Gustafson col. (1, MTEC); Gallatin Co., Gallatin R., West Bozeman, 05 May 1987, D. L. Gustafson col. (4, MTEC); Gallatin Co., Gallatin R. 4700’, 05 May 1987, D. L. Gustafson col. (3, MTEC); as previous but date 15 July 1987 (1, MTEC); as previous but date Aug 1987, pitfall trap (1, MTEC); Gallatin Co., Gallatin R., Bozeman, 03 May 1988, D. L. Gustafson col., (2, MTEC); as previous but date 19 June 1987 (1, MTEC); Gallatin Co., Logan, 8.vii.1990, T. K. Phillips (1, BWPC); Lake Co., Lion Cr. Trail, 26 June 1989, D. L. Gustafson col. (2, MTEC); Missoula Co., Missoula, 20-vii-1988, P. Skelley, blacklight trap (1, MTEC). Nevada: Elko Co., Marys R. Orange Br., 41.5796°N, 115.3578°W, 14 Jul 2004, 1889m, D. L. Gustafson A0088 (1, MTEC). Utah: Sevier Co., Fish Lake, July 5-7, 2006, S,E,M,K. Wells (9, BWPC); Uintah Co., Uinta R. ne Roosevelt, May 13, 1989, S. Wells (1, BWPC); Wasatch Co., Provo R. abv Midway, June 3, 1989, S. Wells (6, BWPC). Wyoming: Yellowstone N. P., 44°55’N, 110°24’W, Lamar Valley, 1993 ungulate carcass study, D. S. Sikes colr./ E. side Yellowst. Riv, NE. of Bridge nr. Tower Jctn. 6080’ (49.74.001N, 5.47.002E)/ Site 5, control, N pitfall trap, 15-22 Jun 1993 (1, MTEC).

Other specimens examined, 2: USA: Washington: Asotin Co., Menatchee Cr trib Grand Ronde R., July 9, 1986 / B. Baumann, S. A. Wells (1, BWPC); Okanogan Co., Lost River above Mazama, July 13, 1988 (1, BWPC) .

Etymology: The specific name is derived from Gallatin County, Montana, where the majority of specimens were collected. Gallatin County, the Gallatin Mountains and the Gallatin River are named after Albert Gallatin, the United States Secretary of Treasury during the Lewis and Clark expedition.

Discussion: The majority of specimens (47) were collected at a single locality over the course of late spring to mid-summer. Based on the specimens above, peak activity is likely in mid-April to Mid-May, before tapering off by the end of July in Montana. There is also a strong association with rivers and creeks, lending support to the hypothesis that Paradonus is a riparian genus.

I have left the two Washington state specimens off of the paratype series, as they co-occur with piceous specimens of P. pectoralis . As these specimens remain undissected, I choose to include them here as specimens seen in case future examinations reveal more about their relationship to the piceous P. pectoralis .

FIG. 18. Paradonus pectoralis , male genitalia, Montana, dorsal view. FIG. 19. P. gallatinensis male genitalia, holotype, dorsal view. FIG. 20. P. gustafsoni male genitalia, paratype, same locality as holotype, dorsal view. FIG. 21. P. stibicki male genitalia, holotype, dorsal view.