Pachybrachis americanus Barney, 2020

1. Pachybrachis americanus Barney , new species

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( Fig. 1 View Fig , Map 1 View Map 1 )

Holotype. Male, labeled “ NEVADA, Clark Co. / 2.9 mi. E. Whitney Pockets , / 36.5337°N, 114.0908°W, / 1280 m, 11-VI-2014, / S.M. Clark & R.L. Johnson [printed, white paper] // HOLOTYPE / Pachybrachis / americanus Barney / R. J. Barney 2020 [printed, red paper]”. Deposited in BYUC. The specimen is point-mounted with genitalia affixed to a second point. It is in excellent condition with all appendages intact. GoogleMaps

Paratypes. Twelve specimens ( 9♂♂ 3♀♀) are labeled “PARATYPE / Pachybrachis / americanus Barney / R. J. Barney 2020 [printed, yellow paper]” GoogleMaps .

Description. Male. Small, pale yellow, very coarsely, diffusely punctate, feebly and obscurely maculate with brown ( Fig. 1 View Fig ); L = 1.85–2.02 mm (mean = 1.96 mm, n = 10); W = 1.00– 1.10 mm (mean = 1.06 mm, n = 10); L/W = 1.82–1.88 (mean = 1.85, n = 10). Head: Distinctly wider than prothoracic apex, HW = 0.73–0.84 mm (mean = 0.79 mm, n = 10); eyes moderately separated, with ocular lines restricted to upper portion of eyes, IOD = 0.22–0.30 mm (mean = 0.25 mm, n = 10); IOD/HW = 0.29–0.36 (mean = 0.31, n = 10); face pale yellow, moderately punctate, median line descending from vertex to middle of eyes; antennae progressing from yellow to brown to black apically, not reaching elytral declivity. Pronotum: Pale yellow, densely punctate, less so at margins, with feeble and obscure M-shaped brown macula; PL = 0.56–0.64 mm (mean = 0.61 mm, n = 10); PW = 0.83–0.93 mm (mean = 0.89 mm, n = 10); PL/ PW = 0.65–0.74 (mean = 0.68, n = 10). Elytra: Pale yellow, densely punctate, striation wanting, feebly and obscurely maculate with brown. Pygidium: Black with 2 oval conjoined yellow spots. Venter: Black with yellow side and apical margins. Legs: Yellow with brown spots, front claws of male not enlarged. Genitalia: Median lobe in en-face view reveals a pronounced extension of the postorificial length (POL), with the apicolateral margins (ALM) protruding beyond the parallel sides of the lobe into wing-like projections or alatates on either side of an extended terminus (T), thus creating a very distinctive distal en-face outline (DEO) ( Fig. 1 View Fig ). The median lobe is relatively narrow in lateral view, with the extended T shown to be a different angle than the alatates. Three males from three USA states were dissected.

Female. As in male, except L = 2.21–2.30 mm (mean = 2.27 mm, n = 3); W = 1.21–1.32 mm (mean = 1.27 mm, n = 3); L/W = 1.73–1.90 (mean = 1.79, n = 3); HW = 0.92–0.96 mm (mean = 0.94 mm, n = 3); IOD = 0.32–0.38 mm (mean = 0.36 mm, n = 3); IOD/HW = 0.34–0.41 ( n = 3).

Etymology. Pachybrachis americanus is named to celebrate, commemorate, and venerate the United States of America, the land of the free and home of the brave, where all people are created equal, each with the right to life, liberty, and the pursuit of happiness.

Remarks. While appearing superficially like several other yellow, densely punctate species, the aedeagal median lobe of P. americanus is very distinctive. Pachybrachis americanus is undoubtedly very closely related to P. densus ; however, P. americanus is significantly larger, with prominent alatates on both sides of the extended aedeagal terminus and without the ridge-like keel of P. densus .

Distribution. This species is known from four western states: Arizona, California, Nevada, and Utah ( Map 1 View Map 1 ).

Biological Notes. A large series of P. americanus was collected on Salicornia sp. (Amaranthaceae) in California.

Specimens Examined. Holotype + 12 paratypes. USA: ARIZONA: Pima Co., Sabino Canyon, 10.viii.1981, A. J. Gilbert & N. J. Smith [ 1♀, AJGC]. CALIFORNIA: Inyo Co.   GoogleMaps , Westgard Pass Tollhouse Area   GoogleMaps , 25.vi.1980, sweeping Salicornia sp. , A. J. Gilbert & R. Gill [ 8♂♂ 1♀, AJGC]; San Diego Co.   GoogleMaps , Jacumba   GoogleMaps , 26.v.1960, D. J. & J. N. Knull [ 1♀, BYUC]. NEVADA: Clark Co.   GoogleMaps , 2.9 mi E Whitney Pockets, 36.5337 o N, 114.0908 o W, 1,280 m, 11.iv.2014, S. M. Clark & R. L. Johnson [ 1♂, HOLOTYPE, BYUC]. UTAH: Washington Co., 6.v.1967, D. R. Harris [ 1♂, AJGC].