Pachybrachis ashfork, 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 : 744-748

13. PACHYBRACHIS ASHfoRk Barney , new species zoobank.org/ urn:lsid:zoobank.org:act:FA53D961-2F60-45B1-A515-DF4CA6543758 ( Figs. 13 , 14B )

Holotype. Male labeled “Ashfork/18-6 [hand-inked] Ar [printed, white paper]//Barber&/ SchwarzColl [printed, white paper]// cylindricus Bowd. [hand-inked, white paper]/ Fall 1915 Revis. [printed, white paper]//[circular blue disc signifying dissection by RJB]// HOLOTYPE / Pachybrachis / ashfork Barney /R. J. Barney 2021 [printed, red paper]”. Deposited in MCZ. The specimen is point-mounted with the genitalia affixed to a second the point. It is in excellent condition with all appendages intact.

Paratypes. Two specimens were labeled “ PARATYPE / Pachybrachis / ashfork Barney /R. J. Barney 2021 [printed, yellow paper]” .

Description. Male. Large, yellow with brown maculae ( Fig. 13 ); L = 3.64 mm (n = 1); W = 1.94 mm (n = 1); L/W = 1.87 (n = 1). Head: Not wider than thoracic apex, HW = 1.37 mm (n = 1); eyes widely separated, without ocular lines, IOD = 0.38 mm (n = 1); IOD/HW = 0.28 (n = 1); face yellow with brown 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 reduced M-shaped brown macula, densely punctate, less so at margins and median line, strongly narrowed apically; PL = 1.30 mm (n = 1); PW = 1.75 mm (n = 1); PL/PW = 0.74 (n = 1). Elytra: Yellow with prominent brown maculae on each elytron prior to declivity, thus appearing as a trans-elytral stripe, densely punctate in baso-sutural area, striae irregular. Pygidium: Brown with 2 oval conjoined yellow spots. Venter: Brown with yellow side and apical margins. Legs: Yellow with brown spots, front claws of male greatly enlarged. Genitalia: Median lobe in en-face view shows large, round OS, with a projecting, grooved terminus, bounded on each side with large wisps at the ALM. The lateral view reveals that apical third of the median lobe is flexed backwards at a 45 ° angle at the wisps insertion at the ALA.A large, rounded keel, projecting from the base to the initiation of the wisps.A sub view of the median lobe shows that the keel has a fissura or split at the most extended point. Two males from two USA states were dissected.

Female. As in male, except L = 4.32 mm (n = 1); W = 2.24 mm (n = 1); L/W = 1.93 (n = 1); HW = 1.67 mm (n = 1); IOD = 0.68 mm (n = 1); IOD/HW = 0.40 (n = 1).

Etymology. This species is named for Ash Fork, Arizona, which is a significant location in the history of Pachybrachis species due to the early collecting by Barber and Schwarz.

Remarks. Externally, P. cylindricus , P. huachuca , and P. ashfork are nearly identical; however, their aedeagal median lobes are readily separable. Pachybrachis ashfork has a very similar median lobe to P. huachuca but the keel has a fissura or split at the most extended point in P. ashfork . This holotype was actually labeled as P. cylindricus by Fall.

Distribution. Specimens were found in Arizona and New Mexico ( Fig. 14B ).

Specimens Examined. Holotype + 2 paratypes. USA: ARIZONA: Yavapai Co., Ash Fork, 18.vi, Barber and Schwarz [1♂ (HOLOTYPE) 1♀, cylindricus Fall 1915 Rev., USNM ]. NEW MEXICO: Grant Co. , 8 mi E Silver City, 15.vii.1971, blacklight, J. R. McClellan [1♂, BYUC].

Figures

Fig. 13. Pachybrachis ashfork, new species, Yavapai Co., Arizona, 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).