Nicrophorus orbicollis Say, 1825

Mullins, Patricia L., Riley, Edward G. & Oswald, John D., 2013, Identification, distribution, and adult phenology of the carrion beetles (Coleoptera: Silphidae) of Texas, Zootaxa 3666 (2), pp. 221-251 : 234-235

Nicrophorus orbicollis Say, 1825

Figs. 15 , 29 , 41 , 54

Necrophorus orbicollis Say, 1825: 177 (see Sikes et al. (2002) for synonymy).

Diagnosis. Body length 13–24 mm, entirely black except for anterior and posterior elytral maculae red-orange; epipleuron entirely black, anteriorly glabrous; anterior and posterior elytral maculae not joined laterally; anterior elytral maculae transverse with borders incised, reaching epipleural ridge, not reaching elytral suture; posterior elytral macula weakly transverse to almost round with borders not incised, not reaching epipleuron or suture. Antennal club orange with basal segment black. Pronotum orbicular with transverse anterior impression, disc glabrous, lateral margins broad. Dorsal surface of elytron with long conspicuous hairs, especially laterally. Epipleural ridge obliterated well before point below humerus. Lateral portion of metasternum sparsely covered with brownish hairs. Posterior lobe of metepimeron glabrous or nearly so. Tarsal empodium bisetose.

Range. Nova Scotia south to Florida, west to Saskatchewan, Nebraska, and Texas (Anderson & Peck 1985, Peck & Kaulbars 1987).

Texas distribution. See Fig. 54 . This species is confined to the Texan and Austroriparian biotic provinces of Texas. It occurs in the following Texas vegetational areas: pineywoods, gulf coast prairies and marshes, post oak savannah and blackland prairies. Confirmed counties (16): Anderson, Angelina, Fannin, Harris, Harrison, Houston, Jasper, Lamar, Madison, Montgomery, Nacogdoches, Polk, Sabine , San Jacinto, Tyler, Walker. Collections: BRC, EGRC, PLM, SFAC, SHSU, TAMU, UTIC.

Seasonality in Texas. See Fig. 41 . The adult seasonality profile of this species (based on 87 occurrence records: Appendix I) is unimodal, with collection records beginning in spring and trailing off in the fall with a large peak in summer.

Biological notes. Anderson and Peck (1985) report that adults of this species are nocturnal and found in open, though more commonly, in forested habitats. In Kansas, this species is found equally in wooded areas and sandy areas (Lingafelter 1995).

Data from examined labels. Collecting methods: black light trap, 15 W black light, black light/ultraviolet light trap, hanging carrion trap, carrion trap, bait trap, pit-fall trap, Malaise trap, flight intercept trap, chicken feather trap, ground-level flight intercept trap. Habitat records: beech–magnolia [Malaise], pine forest [Malaise and flight intercept trap], Osmunda bog [Malaise trap and flight intercept trap], Equisetum bog [Malaise trap], sandy meadow [pit-fall trap]. Carrion records: snake [hanging carrion trap], squirrel [hanging carrion trap], on dead chicken. Miscellaneous: on firing range [black light/UV light trap]. Most specimens from Texas were collected using passive collecting methods, such as malaise traps and flight intercept traps. A few of the Texas specimens were collected at night by light traps. This species is confined to the eastern forested vegetational areas of Texas. Wilson and Fudge (1984) and Trumbo (1991, 1992) published on the reproductive behavior of this species. Trumbo (1990a) published on the ecology of this species in the southeastern United States. Milne and Milne (1944) studied the behavior of this species in the field. Anderson (1982) discussed the natural history of this species.

Figures

FIGURES 12 – 17. Details of Texas Silphidae. 12. Nicrophorus tomentosus, tarsal empodium bisetose; 13. Nicrophorus marginatus, yellow pubescence of posterior lobe of metepimeron, no hairs on dorsal surface of elytra; 14. Nicrophorus marginatus, pronotum. 15. Nicrophorus orbicollis, posterior lobe of metepimeron glabrous, long hairs on dorsal surface of elytra; 16. Nicrophorus pustulatus, pronotum; 17. Nicrophorus mexicanus, pronotum.

FIGURES 24 – 30. Habitus of Texas Nicrophorus. 24, N. americanus; 25, N. carolinus; 26, N. marginatus; 27, N. mexicanus; 28, N. pustulatus; 29, N. orbicollis; 30, N. tomentosus. All scale bars = 10 mm.

FIGURES 37 – 42. Adult seasonality profiles based on occurrence records for Texas Silphidae, Nicrophorinae (part). 37, Nicrophorus americanus; 38, N. carolinus; 39, N. marginatus; 40, N. mexicanus; 41, N. orbicollis; 42, N. pustulatus. For an explanation of occurrence record calculations, see Methods.

FIGURES 50 – 55. Distribution maps for Texas Silphidae, Nicrophorinae (part). 50, Nicrophorus americanus; 51, N. carolinus; 52, N. marginatu s; 53, N. mexicanus; 54, N. orbicollis; 55, N. pustulatus.