Stenus aenescens LYNCH ARRIBALZAGA
Creators: name: Puthz, V.
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Stenus
Stenus aenescens

description: Key to the species of the group of Stenus aenescens LYNCH ARRIBALZAGA   
(DN = depth of apical emargination of sternite 8; LS = length of sternite)  
 1 Forebody densely reticulate.: Unknown. 4.0-4.2mm (FB 2.0-2.1mm). Argentina..................................................................................................................... S. aeneomicans PUTHZ   
- Forebody without reticulation.............................................................................................2  
2 Frons concave with or without a slightly elevated median portion, median portion (mostly) below the level of medial eye margins.................................................................3  
- Frons not concave, elevated median portion extending about to or over the level of medial eye margins...........................................................................................................16  
3 Head broader than elytra or nearly as broad as (HW: EW 0.95).......................................4  
- Head less broad (HW: EW 0,95).....................................................................................11  
4 Median portion on frons complete flat................................................................................5  
- Median portion of frons slightly elevated...........................................................................7  
 5 Interstices of tergite 7 reticulate. 4.5-5.6mm (FB 2.4-2.6mm).: E (fig. 163). Brazil......................................................................................................................... S. teres ERICHSON   
- Interstices of tergite 7 smooth.............................................................................................6  
 6 Head distinctly broader than elytra (HW: EW 1.05). Larger: 4.5-5.0mm (FB 2.3- 2.4mm).: E (fig. 165). Bolivia.......................................................... S. rufipes L. BENICK   
 - Head slightly less broad (HW: EW 0.95). Smaller: 4.0-5.0mm (FB 2.2mm).: E (fig. 164). Brazil........................................................................................... S. riguus L. BENICK   
7 Head distinctly broader than elytra, abdomen distinctly reticulate.....................................8  
 - Head distinctly less broad than elytra (HW: EW 0.94), abdomen without reticulation. 4.3-4.7mm (FB 2.1-1.3mm).: E fig. 167). Brazil............................. S. sodalis L. BENICK   
8 Tergite 10 spadous, posteriorly pointed (figs 148, 150)......................................................9  
 - Tergite ± 10 rounded at posterior margin. 4.2-5.3mm (FB 2.2-2.4mm). Brazil........................................................................................................................ S. curtipennis BERNHAUER   
9 Sternum 9 with a short apicolateral tooth (fig. 156)..........................................................10  
 - Sternum 9 with a longer, acute apicolateral tooth (fig. 149). Brazil. see #8.............................................................................................................................. S. curtipennis BERNHAUER   
 10: E (fig. 166), median lobe acute apically. 3.9-4.7mm (FB 2.1-2.2mm). Brazil........................................................................................................................... S. mantiqueira PUTHZ   
 -: E (fig. 162). median lobe split apically. 4.0-4.8mm (FB 2.1mm). Brazil................................................................................................................................ S. artipennis L. BENICK   
11 Tergite 8 reticulate............................................................................................................12  
 - Tergite 8 not reticulate. 4.0-4.7mm (FB 2.1-2.2mm).: Segment 1 of metatarsi much broader than segment 2, metatibiae compressed medially. Apical notch of sternite 8 deeper (LS: DN=1.9), E (about as in fig. 111, but median lobe longer than parameres). Brazil......................................................................................................... S. cerritus SHARP   
 12 Head broader, HW: EW 0.96. Abdomen shallowly reticulate. 3.6mm (FB 1.8mm).: E (figs. 106, 114). Bolivia.................................................................... S. holmgreni nov.sp.   
- Head less broad, HW: EW 0.90. Anterior tergites not reticulate....................................13  
 13 Tergite 10 slightly concave at apical margin (fig. x).: Metafemur (fig. 131). E (fig. 95). 3.8-4.8mm (FB 2.2-2.3mm). Bolivia........................................... S. femoridens nov.sp.   
- Tergite 10 otherwise..........................................................................................................14  
 14 Tergite 10 evenly rounded at posterior margin (fig. 125).: Metafemur simple. E (fig. 168). 3.6-4.3mm (FB 1.9-2.0mm). Bolivia..................................... S. corticivagans nov.sp.   
 - Tergite 10 very shallowly emarginate at posterior margin................................................15   
 15 Tergite 7 with faint, tergite 8 with distinct reticulation.: E (fig. 112). 3.2-4.1mm (FB 1.9-2.0mm). Peru.............................................................................................. S. inti PUTHZ - Tergites 7 and 8 without reticulation. 3.2-3.8mm (FB 1.8-1.9mm).: Segment 1 of metatarsi simple as are the metatibiae. Apical notch of sternite 8 less deep (SL: DN= 2.4). E (fig. x). Peru............................................................................... S. cerritulus PUTHZ   
16 Tergite 10 with an acute median tip (figs 136, 140, 142)..................................................17  
- Tergite 10 otherwise..........................................................................................................20  
17 Apicomedian tip of tergite 10 minute (fig. 136, 142)........................................................18  
- Apical tip of tergite 10 longer (fig. 140)...........................................................................19  
 18 Tergite 7 densely reticulate, anterior tergites shallowly reticulate.: Unknown. Argentina..................................................................................... S. argentinus BERNHAUER   
 - Tergite 7 not reticulate (at most with traces of reticulation posteriorly).: E (fig. 115). 4.0-4.6mm (FB 2.1-2.2mm). Argentina................................................... S. spicatus nov.sp.   
 19 Larger, head slightly broader than elytra (HW: WÉ =1.01).: Unknown. 4.5-4.8mm (FB 2.2-2.3mm). Paraguay....................................................... S. paraguyanus BERNHAUER   
- Smaller, 3.7-4.3mm. Head slightly narrower than elytra (HW: EW <0.97)......................19  
 20 Tergite 10 (fig. 113). Shoulders rectangular.: E (fig. 136). 3.9-4.3mm (FB 1.7- 1.8mm). Brazil, Paraguay, Argentina............................................ S. plaumannianus PUTHZ   
 - Tergite 10 (fig. 142). Shoulders slightly oblique.: E (fig. 169). 3.7-4.3mm (FB 2.0- 2.1mm)............................................................................................ S. spinuliventris nov.sp.   
21 Tergite 10 distinctly concave at posterior margin (figs 118, 119, 133, 134).....................22  
- Tergite 10 not or shallowly concave at posterior margin (figs 143, 144)..........................25  
 22 Head distinctly narrower than elytra (HW: EW 1.15). Tergite 10 (figs 118, 119).: E (fig. 157): 3.7-4.2mm (FB 2.2.1mm). Argentina, Paraguay, Bolivia, Uruguay.......................................................................................................... S. aenescens LYNCH ARRIBALZÁGA   
- Head less narrower than elytra (HW: EW <1.13).............................................................23  
 23 Abdomen completely, distinctly reticulate.: Sternite 9 (fig. 145), E (fig. 159). 4.0- 4.7mm) FB 2.3-2.4mm). Peru, Bolivia........................................ S. titicacanus BERNHAUER   
- Anterior tergites not (or very shallowly) indistinctly reticulate........................................24  
 24: Apical notch of sternite 8 deeper (LS: DN  5). E (fig. 160). 3.8-4.8mm (FB 1.9- 2.2mm). Chile....................................................................................... S. hogansoni PUTHZ   
 -: Apical notch of sternite 8 less deep (LS: DN =3.9). E (fig. 158). 3.2-3.6mm (FB 2.0mm). Bolivia........................................................................... S. corticihabitans nov.sp.   
 25 Smaller, tergite 8 without reticulation; tergite 10 rounded at posterior margin (fig. 129).: Unknown. 3.0-3.8mm (FB 1.7-1.9mm). Argentina........... S. densepilosus nov.sp.   
- Larger, tergite 8 with distinct reticulation, tergite 10 rounded or slightly emarginate at posterior margin (figs 120, 128, 138)................................................................................26  
 26 Tergite 10 rounded at posterior margin (fig. 120). E (fig. 168). 4.3-5.0mm (FB 2.2- 2.3mm). Argentina................................................................................ S. daguerrei nov.sp.   
- Tergite 10 emarginate at posterior margin........................................................................27  
 27 Punctation and reticulation of tergite 8 deeper and denser (fig. 104), tergite 10 (fig. 128).: E (fig. 116). 3.8-4.2mm (FB 2.0-2.1mm). Argentina, Brazil......................................................................................................................................... S. crassipes BERNHAUER   
 - Punctation and reticulation of tergite 8 less coarse and less deep (fig. 105),: E (fig. 138). 4.0-5.2mm (FB 2.2-2.4mm). Brazil.................................................. S. scissus PUTHZ
description: Published as part of Puthz, V., 2014, Neue und alte neotropische Stenus-Arten (Coleoptera, Staphylinidae) 339. Beitrag zur Kenntnis der Steninen, pp. 1671-1736 in Linzer biologische Beiträge 46 (2) on pages 1720-1721, DOI: 10.5281/zenodo.5311846