Stenus metallicus

Puthz, Volker, 2016, Übersicht über die neotropischen Arten der Gattung Stenus LATREILLE mit seitlich gerandetem Abdomen und ungelappten Tarsen (Coleoptera, Staphylinidae) 350. Beitrag zur Kenntnis der Steninen, Linzer biologische Beiträge 48 (2), pp. 1551-1634 : 1555

Key to the species of the S. metallicus - group

(S= sternum; T= tergum)

1 Brachypterous .....................................................................................................................2

- Macropterous ......................................................................................................................6

2 Brownish .............................................................................................................................3

- Black, elytra with reddish spots...........................................................................................4

3 Punctation of elytra distinctly defined (fig. 306). 6: E (fig. 310). ♀: S8 (fig. 313.). 3.6- 5.0mm (FB 1.9-2.1mm). Costa Rica......................................................... S. electrus PUTHZ

- Punctation of elytra rugose/confluent (fig. 307). 6: E (fig. 308). ♀: S8 (fig. 322). 3.5- 4.2mm (FB 1.9-2.1mm). Costa Rica............................................ S. cerromuertanus PUTHZ

4 Punctation of elytra strongly confluent (fig. 38). EW: EL<1,1mm). 6: E (figs 312). ♀: S8 (about as in fig. 294). 4.0-5.2mm (FB 2.3-2.4mm). Bolivia............................................. .......................................................................................................... S. vermiculifer nov.sp.

- Punctation of elytra distinctly defined.................................................................................5

5 Elytra shorter: EW: EL  1.41, punctation of frons denser, interstices on lateral portions smaller than diameter of punctures. Elytral spot shorter, less long than antennal segments 9-11 combined. 6: E (fig 186, 192). ♀: S8 (fig. 278). 3.8-5.0mm (FB 1.0- 2.0mm). Ecuador.............................................................................. S. clunispicatus PUTHZ

- Elytra longer: EW: EL <1.20, punctation of frons less dense, interstices on lateral portions often larger than diameter of punctures. Elytral spot longer, at least as long as antennal segments 9-10 combined. 6: unknown. ♀: S8 (fig. 298). 4.5-4.5mm (FB 2.3mm). Colombia.......................................................................... S. simpliciclunis PUTHZ

6 Brownish. 6: E (fig. 309). ♀: S8 (fig. 323). 4.0-5.0mm (FB 2.0-2.2mm). Costa Rica ; Panama..................................................................................................... S. fuscatus PUTHZ

- Black, elytra with OR without elytra spots..........................................................................7

7 Elytra uniformely black.......................................................................................................8

- Elytra with reddish/orange spots. (In the following species the elytral spot may become more or less obsolete: S. clavalipenis nov.sp., S. cibdelos nov.sp., S.multispinus nov.sp.)..............................................................................................................................19

8 Larger, FB ≥2.4mm.............................................................................................................9

- Smaller, FB <2.3mm .........................................................................................................13

9 Abdominal punctation coarse and extremely dense, interstices on T7 smaller than half diameter of punctures (e. g. fig. 129) ................................................................................10

- Abdominal punctation less coarse and less dense, interstices on T7 larger than half diameter of punctures (fig. 119) ........................................................................................11

10 6: Metasternum (fig. 155), S8 (figs 140, 141), E (fig. 225). ♀: S8 (fig. 297). 5.0- 5.5mm (FB 2.6-2.7mm). Panama ; Costa Rica................................... S. punctiventris SHARP

- 6: Metasternum (fig. 156), E (fig. 226). ♀: S8 (as in fig. 297). 5.0-6.0mm (FB 2.8mm). Guatemala ; Mexico; Honduras................................................... S. repletus SHARP

11 Black with aeneous lustre, metatibiae bicolorous. 6: E (fig. 210). ♀: S8 (fig. 288). 4.7- 5.7mm (FB 2.5-2.6mm). Mexico...................................................... S. metallicoides PUTHZ

- Black without metallic lustre, metatibiae unicolourous.....................................................12

12 Legs reddish brown. 6: E (figs 184, 193). ♀: S8 (fig. 280). 4.7-5.5mm (FB 2.5- 2.6mm). Panama ; Costa Rica.................................................................. S. corrosus SHARP

- Legs black. 6: Unknown. ♀: S8 (fig. 290). 4.8-5.3mm (FB 2.6mm). Guatemala................ ............................................................................................................. S. nigrivestis nov.sp.

13 Punctation of elytra very dense but mostly distinctly definined........................................14

- Punctation of elytra confluent/rugose................................................................................16 14 Punctation of posterior tergites finer and sparser, interstices on T7 larger, twice and more as large as punctures (fig. 104). 6: E (figs 175, 176, 190). ♀: Unknown. 3.8- 4.3mm (FB 2.2mm). Costa Rica......................................................... S. bierigianus nov.sp. - Punctation of posterior tergites less fine and less sparse, interstices on T7 distinctly less large (figs 119, 124) ..........................................................................................................15 15 Abdominal punctation denser, interstices on lateral half of tergite 5 smaller than half diameter of punctures; T7 (fig. 119). 6: E (figs 205, 211). ♀: S8 (fig. 314). 4.0-4.7mm (FB 2.1-2.3mm). Venezuela; Panama.............................................. S. metallicus ERICHSON - Abdominal punctation less dense, interstices on lateral portion of tergite 5 about as large as punctures, T7 (fig. 124). 6: E (figs 215, 216). ♀: S8 (fig. 292). 3.3-3.7mm (FB 2.1mm). Ecuador..................................................................... S. paucidentatus nov.sp. 16 Smaller, FB ≤2.2mm. Median portion of frons impunctate or sparsely punctate. Sculpture of elytra very coarse and irregular (figs 61, 62) ................................................17 - Larger, FB 2.2mm. Median portion of frons densely punctate. Elytra (fig. 304). E (figs 187, 196, 197). ♀: Unknown. 4.3-5.0mm. Guatemala......................... S. illevigatus nov.sp. 17 Punctation of frons coarser, punctures about as large as median cross section of antennal segment 2. Sculpture of elytra coarser (figs 61, 62). 6: Apical notch of S8 deeper, occupying about posterior half, E (figs 235-237, 248-251). ♀: S8 (fig. 302). 3.5-4.5mm (FB 2.0-2.2mm). Costa Rica; Panama................................ S. trifidus L. BENICK - Punctation of frons less coarse, punctures smaller than median cross section of antennal segment 2. Sculpture of elytra less coarse. 6: Apical notch of S8 less deep.....................18 18 Punctation of forebody less coarse, denser (figs 56, 70). 6: E (figs 206, 212), median lobe with few larger denticles. ♀: S8 (fig. 289). 3.0-4.0mm (FB 1.7-1.8mm). Panama; Costa Rica........................................................................................... S. mucronatus SHARP - Punctation of forebody coarser and less dense (figs 49, 69). 6: E (fig. 199), median lobe without larger denticles. ♀: S8 (about as in fig. 300). 3.5-4.0mm (FB 2.0-2.1mm). Peru.................................................................................................................... inka PUTHZ 19 Each elytron with two spots (the lateral spot extending to epipleurae) OR with one large spot extending laterally to epipleurae................................................................................20 Each elytron with only one elytral spot dorsally ...............................................................31 20 Larger: FB>3.2mm ..........................................................................................................21 - Smaller, FB <2.7mm .........................................................................................................22 21 Dorsal elytral spot larger, sculpture distinctly confluent (fig. 28). 6: Trochanter (fig. 99), E (fig. 221), apical portion of median lobe asymmetrical. S8 (fig. 293). 6.5-7.5mm (FB 3.5mm). Peru; Bolivia; Ecuador; Colombia; Venezuela............. S. perpulcher SOLSKY - Dorsal elytral spot less large, sculpture scarcely confluent (fig. 21). 6: Trochanter (fig. 103), E (fig. 194), median lobe bilateral symmetrical. 5.3-6.8mm (FB 3.3-3.4mm). Colombia; Ecuador................................................................................. S. falcatipes PUTHZ 22 Head broader: HW: EW 0.80-085 .....................................................................................23 - Head less broad: HW: EW ≥0.90 ......................................................................................25 23 Punctation of T7 coarser and denser (fig. 138), elytral spot larger (fig. 38). 6: E (fig. 243, 312). ♀: S8 (about as in fig. 294). 4.0-5.2mm (FB 2.3-2.4mm). Bolivia...................... .......................................................................................................... S. vermiculifer nov.sp. - Punctation of T7 less coarse and less dense (fig. 127), elytral spot less large (e. g. fig. 52) .....................................................................................................................................24 24 Elytra broader: EW: EL  1.06 (fig. 52). 6: E (figs 222, 233). ♀: S8 (fig. 294). 4.3- 5.3mm (FB 2.4-2.5mm). Colombia.................................................. S. perscabratus nov.sp. - Elytra less broad: EW: EL  1.11 (fig. 19). 6: Unknown. ♀: S8 (fig. 279). 4.0-4.8mm