Oiceoptoma, Leach, 1815

Sommer, David, Růžička, Jan, Nishikawa, Masaaki & Schneider, Jan, 2021, Oiceoptoma tangi (Coleoptera: Silphidae: Silphinae), a new species of carrion beetle from eastern China, Zootaxa 4949 (3), pp. 445-472 : 470-471

Modified key to Palaearctic Oiceoptoma (modified from Růžička et al. 2004)

The following couplets are modified to accommodate the newly described species.

5. Pronotum with diffuse median spots (usually composed of several scattered darker spots or almost indistinct, Figs. 4B, E ). Scutellum more distinctly punctured medially than laterally ( Fig. 6B ). Elytra brown to black, subapical surface with rugosities ( Figs. 2A, D , 9C ). Male genital segment with ventrite 9 anteriorly distinctly longer than tergum 9 in ventral view ( Fig. 12E ).— Proventrite with dense punctation laterally; medially dark brown to black, laterally only narrowly orange in ventral view ( Fig. 5B ). Median lobe of aedeagus subapically distinctly sinuous laterally, tapering to a widely rounded apex ( Figs. 11C–D ). Basal portion oval, robust, not exceeding the width of aedeagus ( Figs. 11C–D ). Female tergum 7 posteriorly with wide, only weakly expressed emargination ( Fig. 16A ). Female tergum 8 truncate posteriorly ( Fig. 13C ). (Central and north-eastern China, Far East of Russia, Korean Peninsula to Japan)..................................................... O. subrufum (Lewis)

– Pronotum with four black distinct spots, arranged in a trapezoidal pattern ( Figs. 4A, C ). Scutellum with homogeneous punctation ( Figs. 6A, C ). Elytra subapically with simple surface ( Figs. 1A, D , 2E , 3A , 9A–B, D ). Male genital segment with ventrite 9 anteriorly as long as tergum 9 in ventral view ( Figs. 12D, F ).................................................. 6

6. Spots on pronotum distinctly delimited, smooth and glossy, only with sparsely distributed, minute punctures with very short setae ( Figs. 4C, F ). Proventrite with only minute, superficial punctation laterally; completely dark brown to black in ventral view ( Fig. 5C ). Elytra black ( Figs. 2E , 3A , 6F , 9D ). Apex of elytron short and rounded in female ( Figs. 2E ). Surface of scutellum and elytra with very weak, superficial punctation ( Figs. 6C, F , 9D ). Median lobe of aedeagus gradually tapered to a slender, sharp apex ( Fig. 11E ). Basal portion oval, less robust, not exceeding the width of aedeagus ( Fig. 11E ). Female tergum 7 posteriorly simple, without emargination ( Fig. 16C ). Female tergum 8 broadly truncate posteriorly ( Fig. 14A ). Female ventrites 5 and 6 longer medially, posteriorly exposing only a shorter area of brick-wall pattern ( Figs. 14B , 15E ). ( Japan)............................................................................................... O. nigropunctatum (Lewis)

– Spots on pronotum vaguely delimited, regularly covered with fine, distinct punctures, covered by long, orange setation ( Figs. 4A, D ). Proventrite with dense punctation laterally; medially dark brown to black, laterally widely orange in ventral view ( Fig. 5A ). Elytra light to dark brown ( Figs. 1A, D , 6D , 9A–B ). Apex of elytron elongated to blunt tip in female ( Figs. 1D , 8A , 9B ). Surface of scutellum and elytra with distinct, deep punctation ( Figs. 6A, D , 9A–B ), Median lobe of aedeagus gradually tapered to widely rounded, triangular apex ( Figs. 11A–B ). Basal portion widely oval, very narrow, markedly exceeding the width of aedeagus ( Figs. 11A–B ). Female tergum 7 posteriorly with narrow, deep emargination ( Fig. 17A ). Female tergum 8 regularly rounded posteriorly ( Figs. 13A , 17A ). Female ventrites 5 and 6 very short medially, posteriorly with long area of brick-wall pattern ( Figs. 15A–B, F ) ( China: Zhejiang Province). .... O. tangi Sommer, Růžička, Nishikawa & Schneider , new species

Figures

FIGURE 1. A–F. Habitus of Oiceoptoma tangi Sommer, Růžička, Nishikawa & Schneider, new species: A–C holotype male, D–F paratype female, Pinxi Creek; A, D—dorsal view, B, E—ventral view, C, F—lateral view. Scale 2 mm.

FIGURE 2. A–D. Habitus of Oiceoptoma subrufum (Lewis, 1888): A–C male, D—female. E. Habitus of O. nigropunctatum (Lewis, 1888), female. A, D, E—dorsal view, B—ventral view, C—lateral view. Scale 2 mm.

FIGURE 3. A–C. Habitus of Oiceoptoma nigropunctatum (Lewis, 1888), male. A—dorsal view, B—ventral view, C—lateral view. Scale 2 mm. D–F. Details of O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, male paratype, Pinxi Creek. D—head dorsally, E—head ventrally, F—humerus of elytra in dorsal view.

FIGURE 4. A–C. Pronotum of Oiceoptoma in dorsal view. D–F. Detail of pronotal disc of Oiceoptoma in dorsal view.A, D—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, Pinxi Creek, B, E—O. subrufum (Lewis, 1888), C, F—O. nigropunctatum (Lewis, 1888).

FIGURE 5. A–C. Proventrite of Oiceoptoma in ventral view. D–F. Detail of pronotal margin of Oiceoptoma in dorsal view. A, D—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, Pinxi Creek, B, E—O. subrufum (Lewis, 1888), C, F—O. nigropunctatum (Lewis, 1888).

FIGURE 6. A–C. Scutellum of Oiceoptoma in dorsal view. D–F. Detail of right elytron of Oiceoptoma in dorsal view.A, D—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, Pinxi Creek, B, E—O. subrufum (Lewis, 1888), C, F—O. nigropunctatum (Lewis, 1888).

FIGURE 8. A, B. Left elytron of Oiceoptoma in ventral view. C. Detail of punctation on elytron of Oiceoptoma in ventral view. D. Head of Oiceoptoma in dorsal view. A, C, D—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, female paratype, Pinxi Creek. B—O. subrufum (Lewis, 1888). D—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, male holotype.

FIGURE 9. A–D. Right elytron of Oiceoptoma in dorsal view. A—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, male paratype, Pinxi Creek, B—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, female paratype, Pinxi Creek, C—O. subrufum (Lewis, 1888), male, D—O. nigropunctatum (Lewis, 1888), male.

FIGURE 11. A–E. Aedeagus of Oiceoptoma. A, B—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, paratype, Pinxi Creek, ventral and dorsal view. C, D—O. subrufum (Lewis, 1888), ventral and dorsal view. E—O. nigropunctatum (Lewis, 1888), ventral view.

FIGURE 12. A–E. Male tergum 9 and 10 of Oiceoptoma. A, D—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, paratype, Pinxi Creek. B, E—O. subrufum (Lewis, 1888). C, F—O. nigropunctatum (Lewis, 1888).A–C—dorsal view, D–E—ventral view. sg—spiculum gastrale, t9—tergum 9, t10—tergum 10, v9—ventrite 9.

FIGURE 13. A–E. Female genitalia of Oiceoptoma. A, B—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, paratype, Pinxi Creek. C, D—O. subrufum (Lewis, 1888).A, C—dorsal view, B, D—ventral view. c—coxite, s—stylus, t8—ter- gum 8, t9—tergum 9, t10—tergum 10, v8—ventrite 8, v9—ventrite 9.

FIGURE 14. A–B. Female genitalia of Oiceoptoma. A, B—O. nigropunctatum (Lewis, 1888). A—dorsal view, B—ventral view. C–H. Protarsus of Oiceoptoma. C–E—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, holotype in dorsal view, paratypes (Pinxi Creek) in ventral view. F—O. nigropunctatum (Lewis, 1888). G, H—O. subrufum (Lewis, 1888). C, F, G –male, dorsal view. D—male, ventral view. E, H—female, ventral view. t8–10—tergum 8–10, v6–9—ventrite 6–9.

FIGURE 15. A–E. Female abdomen of Oiceoptoma, ventral view. A, B, F—O. tangi Sommer, Růžička, Nishikawa & Schnei- der, new species, paratype, Pinxi Creek. C, D—O. subrufum (Lewis, 1888). E—O. nigropunctatum (Lewis, 1888). bwp—brickwall pattern, v4–v7—ventrite 4–7.

FIGURE 16. A–E. Female segments 7 and 8 of Oiceoptoma. A, B—O. subrufum (Lewis, 1888). C, D—O. nigropunctatum (Lewis, 1888). A, C—dorsal view, B, D—ventral view. t7—tergum 7, t8—tergum 8, v7—ventrite 7, v8—ventrite 8.

FIGURE 17. A–B. Female abdomen of Oiceoptoma, dorsal and ventral views. C. Head of Oiceoptoma, lateral view. A, B—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, female paratypes, Pinxi Creek. C—O. tangi Sommer, Růžička, Nishikawa & Schneider, new species, male holotype. ant—antenna, c—coxite, ce—compound eye, cr—crest, s—stylus, t7–9— tergum 7–9, v5–8—ventrite 5–9.