Stenocerus, Schoenherr, 1826

Lopes, Marcela Paes De A. M. & Mermudes, José Ricardo M., 2018, Four new species and new synonymy in Stenocerus Schoenherr, 1826 (Coleoptera, Anthribidae, Anthribinae, Stenocerini), Zootaxa 4472 (3), pp. 471-488 : 487

Key to Stenocerus species

1. Intercoxal process of mesosternum spatulate, amply impressed, not swollen at apical and lateral margins ( Figs. 22 , 50 )..... 2

- Intercoxal process of mesosternum not spatulate, with groove or tubercle ( Figs. 8 , 36 , 60, 61 )......................... 6

2. (1). Disc of pronotum evenly convex, lacking grooves or impressions, with dark hexagonal spot, wider at base, delimited by yellowish scales. Elytra with a large dark rounded spot................................. S. sigillatus Jordan, 1906 ( Brazil)

- Disc of pronotum with medial depression or grooved ( Fig. 20 ). Elytra lacking large dark rounded spot ( Fig. 23 )........... 3

3. (2). Elytra with checkered pattern on interstriae 1, alternate black spots at median third arranged obliquely on interstriae 3, 4, 5 and 7, almost forming a stripe ( Figs 15 , 23 )................................................ S. fratris sp. nov. ( Brazil)

- Elytra vestiture not as above, and lacking transverse post-median stripe........................................... 4

4. (3). Intercoxal process of mesosternum impressed at apex, anterior margin concave, lacking latero-apical expansion, sides sinuous and feebly convergent, and posterior margin subrounded ( Fig. 50 ).................... S. mesosternalius sp. nov. ( Brazil)

- Intercoxal process of mesosternum very feebly impressed at apex, lacking latero-apical expansion, sides strongly convergent, and posterior margin broadly rounded..................................................................... 5

5. (4). Antennae with elongate, fine and erect setae only at apex of antennomere III. Ventrites I–IV (in males) with medial tuft................................................... S. varipes Fahraeus, 1839 ( Costa Rica, Ecuador, Brazil and Bolivia)

- Antennae with elongate, fine and erect setae, throughout antennomeres III-XI. Ventrites I –IV (in males) lacking medial tuft.......................................... S. angulicollis Jekel, 1855 (Mexico, Central America, Colombia and Brazil)

6. (1). Head with red vertex. Disc of pronotum with two longitudinal deep grooves lined with pale yellowish pubescence......................................................... S. frontalis Gyllenhal, 1833 ( Costa Rica, French Guiana and Brazil)

- Head with brown to black vertex. Disc of pronotum with weak medial impressions, concolorous with sides (without longitudinal groove or stripe)................................................................................... 7

7. (6). Intercoxal process of prosternum lacking impression or grooves................................................. 8

- Intercoxal process of prosternum impressed or grooved...................................................... 10

8. (7). Dorsal vestiture of pronotal disc with minute circular central spot formed by dark scales. Intercoxal process of mesosternum with apical margin biconvex. Tarsomeres I and II yellowish............ S. fulvitarsis (Germar, 1824) ( Brazil and Paraguay)

- Dorsal vestiture of pronotal disc entirely black, either with or lack a large gray or yellow triangle. Intercoxal process of mesosternum with apical margin convex. Tarsomeres I and II yellowish or darkened..................................... 9

9. (8). Elytral vestiture with dense yellowish scales, at middle and apex with black scales giving an hourglass appearance, interstriae 1 and 3 with subrounded black spots (or the yellowish vestiture more restricted, not forming transverse stripe at apical declivity)................ S. nigrotessellatus Blanchard, 1847 ( Costa Rica, Panama, Ecuador, Bolivia, Peru, Guyana and Brazil)

- Elytral vestiture darkened, with distinct transverse yellowish stripe at beginning of apical declivity ( Fig. 29 )............................................................................................... S. similis sp. nov. ( Peru)

10. (7). Intercoxal process of mesosternum with apical margin concave and bituberculate..................................................................... S. longulus Jekel, 1855 ( United States (Texas), Mexico, Central and South America)

- Intercoxal process of mesosternum with apical margin not tuberculate. ( Fig 8 )................ S. christus sp. nov. (Brazil)

Figures

FIGURES 17–28. Stenocerus fratris sp. nov., holotype male: 17, head, dorsal view; 18, head, lateral view; 19, antenna; 20, pronotum; 21, prothorax, lateral; 22, mesosternal process; 23, elytra, dorsal; 24, abdomen, ventral; 25, pygidium, dorsal; 26, tergite and sternite VIII, ventral; 27, tegmen, dorsal and lateral; 28, penis, dorsal and lateral.

FIGURES 45–56. Stenocerus mesosternalius sp. nov., holotype male: 45, head, dorsal view; 46, head, lateral view; 47, antennae; 48, pronotum; 49, prothorax, lateral; 50, mesosternal process; 51, elytra, dorsal; 52, abdomen, ventral; 53, pygidium, dorsal; 54, segment VIII (tergite and sternite) ventral; 55, tegmen dorsal and lateral; 56, penis dorsal and lateral.

FIGURES 3–14. Stenocerus christus sp. nov., holotype male: 3, head, dorsal view; 4, head, lateral view; 5, antenna; 6, pronotum; 7, prothorax lateral; 8, mesosternal process; 9, elytra dorsal; 10, abdomen, ventral; 11, pygidium dorsal; 12, tergite and sternite VIII ventral; 13, tegmen dorsal and lateral; 14, penis dorsal and lateral.

FIGURES 31–42. Stenocerus similis sp. nov., holotype male: 31, head, dorsal view; 32, head, lateral view; 33, antenna; 34, pronotum; 35, prothorax, lateral; 36, mesosternal process; 37, elytra dorsal; 38, abdomen, ventral; 39–42, paratype male: 39, pygidium, dorsal; 40, tergite and sternite VIII, ventral; 41, tegmen, dorsal and lateral 42, penis dorsal and lateral.

FIGURES 60–62. Stenocerus fulvitarsis: 60–61, mesosternal process, with variations of anterior margin; 62, head, dorsal view (longitudinal carinae indicate by: 1, median carina; 2, lateral carina small; 3, without lateral carina evident). Sample of the possibility of specimens without lateral carina.

FIGURES 15–16. Stenocerus fratris sp. nov., holotype male from Santa Maria de Jetibá (Espírito Santo): 15, dorsal; 16, lateral.

FIGURES 29–30. Stenocerus similis sp. nov., holotype male from Mariscau, Juanjuí (Peru): 29, dorsal; 30, lateral.