Thanatophilus truncatus (Say, 1823)

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 : 229-230

Thanatophilus truncatus (Say, 1823)

Figs. 23 , 36 , 49

Silpha truncata Say, 1823: 193 (see Peck and Miller (1993) for synonymy).

Diagnosis. Body length 12–16 mm, broadly subparallel, entirely dull black. Head with small eyes, without short row of long erect hairs behind each eye. Pronotum broadest at base, disc lacking pubescence. Elytral apices conjointly truncate to subtruncate; disc without costae, smooth, finely granulose; epipleuron oblique, wider at base than apex, coloration not differing from remainder of body. Hind femur of males unmodified.

Range. Nebraska south to Texas, west to southern New Mexico and Arizona (Peck & Kaulbars 1987), and south to central Mexico (Peck & Anderson 1985).

Texas distribution. See Fig. 49 . This species is almost entirely confined to the Kansan, Chihuahuan, and Navahonian biotic provinces of Texas, with a single record from the Balconian province (Sutton County in central Texas). It occurs in the following Texas vegetational areas: Edwards Plateau, rolling plains, high plains, and trans- Pecos. Confirmed counties (14): Brewster, Briscoe, Culberson, El Paso, Gray, Hemphill, Jeff Davis, Lubbock, Oldham, Presidio, Randall, Reeves, Sutton, Terrell. Collections: EGRC, LSAM, MWSU, PLM, SFAC, SRSU, TAMU, TTU, UTIC, WTAM.

Seasonality in Texas. See Fig. 36 . The adult seasonality profile of this species (based on 73 occurrence records: Appendix I) is unimodal, with a large peak in summer.

Biological Notes. This species occurs in arid and open habitats (Peck & Anderson 1985). In Kansas, this species was captured in largely open sandy prairies (Lingafelter 1995).

Data from examined labels. Collecting methods: pit-fall trap, baited pit-fall trap, dung trap, carrion trap, human feces pit-fall trap. Habitat records: pine-fir [carrion trap in Guadalupe National Park], oak–fir–ponderosa pine [dung trap in Big Bend National Park], maple forest [dung trap]. Carrion records: deer (dry and fresh), pig, turkey vulture, Sylvilganus auduboni carrion, Lepus californicus carrion, cow and bobcat. Miscellaneous: some specimens were also collected at night. This species is restricted to the arid regions of west Texas. Life history data for this species are lacking.

Figures

FIGURES 18 – 23. Habitus of Texas Silphidae. 18, Necrophila americana; 19, Necrodes surinamensis; 20, Oiceoptoma inaequale; 21, O. noveboracense; 22, O. rugulosum; 23, Thanatophilus truncatus. All scale bars = 10 mm.

FIGURES 31 – 36. Adult seasonality profiles based on occurrence records for Texas Silphidae, Silphinae. 31, Necrophila americana; 32, Necrodes surinamensis; 33, Oiceoptoma inaequale; 34, O. noveboracense; 35, O. rugulosum; 36, Thanatophilus truncatus. For an explanation of occurrence record calculations, see Methods.

FIGURES 44 – 49. Distribution maps for Texas Silphidae, Silphinae. 44, Necrophila americana; 45, Necrodes surinamensis; 46, Oiceoptoma inaequale; 47, O. noveboracense; 48, O. rugulosum; 49, Thanatophilus truncatus.