Pachybrachis peninsularis, Fall, 1915

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 : 739-742

10. PACHYBRACHIS peNINSULARIS Fall, 1915 ( Figs. 10 , 14B )

Pachybrachys peninsularis Fall 1915: 368 .

Type. Fall’s (1915) type male, hereby designated lectotype, labeled “San Felipe/Low, Cal. [printed, white paper]//TYPE [printed]/ peninsula / ris [hand-inked, white paper]//M.C.Z./Type [printed]/24963 [hand-inked, red paper]//H.C. FALL /COLLECTION [printed, white paper]//[circular blue disc signifying dissection by RJB]// LECTOTYPE / Pachybrachys / peninsularis Fall /R. J. Barney 2021 [printed, red paper]”, was examined, dissected, and photographed ( Fig. 10 ).

Redescription. Male. Large, yellow and brown maculate ( Fig. 10 ); L = 3.61 mm (n = 1); W = 1.99 mm (n = 1); L/W = 1.82 (n = 1). Head: Not wider than thoracic apex, HW = 1.27 mm (n = 1); eyes closely separated, without ocular lines, IOD = 0.25 mm (n = 1); IOD/HW = 0.19 (n = 1); face yellow with large, brown W-shaped macula connecting the vertex and bases of antennae and up to bases of upper lobes of eyes, punctation dense in dark areas, antennae progressing from yellow to brown, not reaching elytral declivity. Pronotum: Yellow with broad, diffuse M-shaped brown macula, densely punctate, less so at margins and median line, strongly narrowed apically; PL = 1.29 mm (n = 1); PW = 1.84 mm (n = 1); PL/PW = 0.70 (n = 1). Elytra: Yellow with standard brown maculae, densely punctate in baso-sutural area, striae irregular. Pygidium: Dark brown with 2 oval conjoined yellow spots. Venter: Dark 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, oval OS, with a wide projecting triangular terminus, bounded on each side with large wisps at the ALM. The lateral view reveals a small keel, projecting from the base to the initiation of the wisps.A sub view of the median lobe shows that the keel ridge is very sharp. One male from Baja California, Mexico was dissected.

Remarks. Fall (1915) described P. peninsularis as “nearly identical” to P. turgidicollis . This is true externally, but the median lobes are easily separable. The only specimen of P. peninsularis known to me is the lectotype, which is from Mexico. This species was not listed by Riley et al. (2003).

Distribution. The only confirmed specimen I have seen is the lectotype from Baja California, Mexico ( Fig. 14B ).

Specimens Examined. Lectotype. MEXICO: Lower Baja California: San Felipe [1♂, LECTOTYPE, MCZ-FALL].

Figures

Fig. 10. Pachybrachis peninsularis, Baja California, Mexico, 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).