Pachybrachis morosus Haldeman, 1949

Barney, Robert J., 2019, Definition and Revision of the Pubescens Species-Group of North American Pachybrachis Chevrolat (Coleoptera: Chrysomelidae: Cryptocephalinae), Including Descriptions of Three New Species, The Coleopterists Bulletin 73 (4), pp. 1017-1048 : 1028-1029

6. Pachybrachis morosus Haldeman, 1949 ( Figs. 6 , 13C, D ; Map 1B)

Pachybrachys pubescens: sensu Olivier 1808 , not Fabricius 1777. Jacoby 1889: 136 (taxonomy); Fall 1915: 326 (taxonomy).

Pachybrachis morosus Haldeman 1849: 260 . Melsheimer 1853: 126 (catalogue);

LeConte 1880: 205 (taxonomy); Blatchley 1910: 1127 (taxonomy); Riley et al. 2003: 156 (catalogue).

Pachybrachys haematodes Suffrian 1852: 150 . New synonymy.

Jacoby 1889: 64 (taxonomy); Fall 1915: 326 (taxonomy).

Pachybrachis haematodes: Riley et al. 2003: 156 (catalogue).

Types. Haldeman’ s female type of P. morosus in the LeConte Collection (MCZ-LEC), labeled “[circular orange disc] // TYPE [printed] / 8403 [handinked, red paper] // P. morosus Hald. / pubescens ≠ Oliv. [hand-inked, white paper] // LECTOTYPE / Pachybrachis / morosus Haldeman 1849 / design. R. J. Barney 2019 [printed, red paper]”, was examined and photographed and is hereby designated lectotype to stabilize the epithet ( Fig. 13C ). LeConte’ s orange disc is thought to represent the “Southern states”. LeConte’ s Collection also holds six (2♂♂ 4♀♀) beetles, of which two females had some orange-red coloring, labeled “Tex. // PARALECTOTYPE / Pachybrachis / morosus Haldeman 1849 / design. R. J. Barney 2019 [printed, yellow paper]”.

A male P. haematodes in the Bowditch Collection ( MCZ-BOW), labeled “Jalapa, / Mexico. / Hoege. // 1 st Jacoby / Coll. [printed, white paper] // MCZ- ENT / barcode / 00739478 // [circular blue disc signifying dissection by RJB]”, was examined, dissected, and photographed ( Fig. 13D ). Additionally, two females in the Bowditch Collection were labeled “Misc [?] // Jacoby 2 nd / Coll. // MCZ- ENT / barcode / 00739479” and “ Durango [handinked, white paper] // 164 [hand-inked, white paper] // Miscique [?][hand-inked, white paper] // 449 [printed] // Jacoby 2 nd / Coll. // MCZ-ENT / barcode / 00739480” .

Redescription. Male. Large, black, dense and uniformly punctured, often with orange-red markings on all body parts, sparsely covered in white pubescence; L = 2.61–3.29 mm (mean = 3.05 mm, n = 24); W = 1.46–1.94 mm (mean = 1.70 mm, n = 24); L/W = 1.64–1.86 (mean = 1.73, n = 24). Head: Not distinctly wider than thoracic apex, HW = 0.94–1.18 mm (mean = 1.06 mm, n = 24); eyes widely separated,IOD = 0.40–0.58 mm (mean = 0.47 mm, n = 24); IOD/HW = 0.35–0.52 (mean = 0.43, n = 24); face primarily black with dense, white, recumbent pubescence; antennae black, not reaching elytral declivity. Pronotum: Black, often with orange-red markings, sparsely covered with white, recumbent pubescence, widest at base; PL = 0.90–1.18 mm (mean = 1.02 mm, n = 24); PW = 1.34–1.75 mm (mean = 1.55 mm, n = 24); PL/PW = 0.59–0.73 (mean = 0.63, n = 24). Elytra: Black, often with orange-red markings, sparsely covered with white, recumbent pubescence. Pygidium: Black with white pubescence. Venter: Black with white pubescence. Legs: Black with white pubescence; front claws not enlarged. Genitalia. Median lobe in en-face view with large OS, parallel sides rounding to nodule with visible setae on each side; base to nodule very straight in lateral view. Nineteen males from 17 USA states and two Mexican states were dissected.

Female. As in male, except L = 2.89–3.88 mm (mean = 3.40 mm, n = 28); W = 1.65–2.32 mm (mean = 2.00 mm, n = 28); L/W = 1.58–1.87 (mean = 1.71, n = 28); HW = 1.06–1.29 mm (mean = 1.19 mm, n = 28); IOD = 0.46–0.70 mm (mean = 0.60 mm, n = 28); IOD/HW = 0.42–0.59 (mean = 0.50, n = 28).

Remarks. Suffrian (1852) described P. haematodes as differing from P. pubescens (= P. morosus ) only in the appearance of “blood-red spots on almost all parts of the body”. Suffrian mentions seeing males and females from Oaxaca, Mexico, without designating a type. Fall (1915) had P. pubescens and P. haematodes numbered as his first two species. He remarked that he was not sure of “their specific distinctness” and noted that P. pubescens is the equivalent of P. morosus . Fall made no mention of seeing any types of either species.

Distribution. Pachybrachis morosus is found from the eastern seaboard of the USA to southern Mexico (Map 1B). The localities of examined specimens were plotted to illustrate the distribution of the two color forms, entirely black vs. orange-red marked, of the species.

Biological Notes. Quercus is undoubtedly a host plant of P. morosus . All-black specimens were collected on Q. falcata and Q. marilandica in Kentucky and Quercus sp. in Florida. Clark et al. (2004) reported P. morosus in association with Q. buckleyi , Q. fusiformis , and Q. incana in Texas and Quercus sp. in Wisconsin.

Specimens with orange-red markings were found on Q. undulata and Q. gambelii in New Mexico and on A. rigidula in Texas. Clark et al. (2004) reported P. haematodes in association with A. rigidula , Q. fusiformis , and Q. mohriana in Texas.

Specimens Examined. See Appendix 6.

Figures

Fig. 6. Pachybrachis morosus, Logan Co., Kentucky. A–B) Dorsal and lateral habitus, respectively, C) Face, D) Pygidium, E–F) Median lobe of aedeagus, lateral and en-face views, respectively.

Fig. 13. Pachybrachis species, type specimens. A) P. connexus (female), B) P. integratus (female), C) P. morosus (female), D) P. haematodes (male), E) P. analis (female), F) P. marmoratus (female), G) P. desertus (male), H) P. brunneus (male), I) P. uteanus (male).