Pachybrachis ephedra, Barney, 2021

Barney, Robert J., 2021, Definition and Revision of the cylindricus Species-Group of North American Pachybrachis Chevrolat (Coleoptera: Chrysomelidae: Cryptocephalinae), Including Descriptions of Six New Species, The Coleopterists Bulletin 75 (4), pp. 723-748 : 737-739

8. PACHYBRACHIS epHeDRA Barney , new species zoobank.org/ urn:lsid:zoobank.org:act:09221B9C-7B99-46B2-B6C6-983A0451B38B ( Figs. 8 , 14B )

Holotype. Male labeled “ UTAH: Washington Co./ 4.7 km SE Hurricane / 37.1442°N, 113.2540° W / 17.v.2015, S. M. Clark & E. G. Riley [printed, white paper]// HOLOTYPE / Pachybrachis / ephedra Barney /R. J. Barney 2021 [printed, red paper]”. Deposited in BYUC. The specimen is point-mounted with the genitalia affixed to a second point. It is in excellent condition with all appendages intact.

Paratypes. Three specimens (2♂♂ 1♀), including two (1♂ 1♀) from the holotype series, are labeled “ PARATYPE / Pachybrachis / ephedra Barney / R. J. Barney 2021 [printed, yellow paper]”.

Description. Male. Large, whitish yellow with black maculae and black pronotal M ( Fig. 8 ); L = 3.77–3.94 mm (mean = 3.85 mm, n = 3); W = 1.99–2.17 mm (mean = 2.10 mm, n = 3); L/W = 1.78–1.91 (mean = 1.84, n = 3). Head: Not wider than thoracic apex, HW = 1.30–1.38 mm (mean = 1.36 mm, n = 3); eyes moderately separated, without ocular lines, IOD = 0.31–0.36 mm (mean = 0.33 mm, n = 3); IOD/HW = 0.22–0.26 (mean = 0.24, n = 3); face yellow with large black macula descending from the vertex and between the upper lobes of eyes, punctation dense in dark areas, antennae progressing from yellow to brown, not reaching elytral declivity. Pronotum: Yellow with large M-shaped black macula, densely punctate, less so at margins and median line, strongly narrowed apically; PL = 1.18–1.37 mm (mean = 1.34 mm, n = 3); PW = 1.77–1.96 mm (mean = 1.90 mm, n = 3); PL/PW = 0.67–0.72 (mean = 0.70, n = 3). Elytra: Whitish yellow with prominent black maculae on each elytron prior to declivity, thus appearing as a trans-elytral stripe, densely punctate in baso-sutural area, striae irregular. Pygidium: Black with 2 oval conjoined yellow spots. Venter: Black with yellow side and apical margins. Legs: Yellow with brown/black spots, front claws of male greatly enlarged. Genitalia: Median lobe in en-face view shows a large, oval OS, with a wide projecting terminus, bounded on each side with wisps at the ALM. The lateral view reveals a large, darkened, sharp-edged keel, projecting from near the base to the T. A sub view of the median lobe shows that the keel ridge is not grooved or split. Three males from two USA states were dissected.

Etymology. This species is named for the presumed host plant, Ephedra torreyana.

Remarks. The P. ephedra specimens were part of a series of four (3♂♂ 1♀) beetles collected from E. torreyana in Utah. I initially assumed these were all the same species, but dissection of the males revealed two distinct median lobes. The median lobe of P. ephedra has a distinct sharp-edged keel, while the median lobe of P. hurricane is smooth and rounded. The singleton female cannot be assigned to either species at this time, but measurements are here provided: L = 4.12 mm (n = 1); W = 2.22 mm (n = 1); L/W = 1.85 (n = 1); HW = 1.51 mm (n = 1); IOD = 0.54 mm (n = 1); IOD/HW = 0.36 (n = 1).

Distribution. This species was found in California and Utah ( Fig. 14B ).

Biological Notes. This species was collected on Ephedra torreyana in Utah.

Specimens Examined. Holotype + 2 paratypes. USA: CALIFORNIA: San Bernardino Co., Morongo Valley , 28.v.1941, D. J. and J. N. Knull [1♂, OSUC]. UTAH: Washington Co., 4.7 km SE Hurricane, 37.1442°N 113.2540°W, 17.v.2015, S. M. Clark and E. G. Riley [1♂, HOLOTYPE, BYUC]; same data, except ex. Ephedra torreyana, R. J. Barney [1♂, RJBC].

Figures

Fig. 8. Pachybrachis ephedra, new species, Washington Co., Utah, holotype.A) Dorsal habitus, B) Lateral habitus, C) Face, D) Pygidium, E) Median lobe of aedeagus, lateral view, F) Median lobe of aedeagus, en-face view, G) Median lobe of aedeagus, sub view.

Fig. 14. Distribution of Pachybrachis species, based only upon specimens examined in this study. A) P. hybridus (black), P. turgidicollis (red), P. texasensis, new species (green), P. chaoticus (blue), P. pinguescens (orange), P. crassus (purple), B) P. saguaro, new species (black), P. peninsularis (purple), P. cylindricus (red), P. huachuca, new species (orange), P. hurricane, new species (gray), P. ephedra, new species (blue), and P. ashfork, new species (green).