Key to males of Solenopsidini genera

Key to genera of Solenopsidini (subfamily Myrmicinae) based on males.

This key was developed by Chung et al. (2025), with reference to Kempf (1974), DuBois (1986), Bolton (1987), Kugler (1994), Heterick (2001), Fernández (2003b), Cover & Deyrup (2007), Feitosa et al. (2008), Bahktiar et al. (2009), Silva et al. (2009), Ito & Yamane (2014), Pitts et al. (2018), Yamane & Jaitrong (2019) and Ramamonjisoa et al. (2023), as well as specimens available on AntWeb. The classification of forewing venation follows that of Cantone (2017).

1

• Forewing venation of Typology IV, with submarginal cell (SMC) absent (Fig. 12A) => Adelomyrmex
• Forewing venation of Typology I - III, with submarginal cell(s) present (Fig. 12AA) => 2

• 

  Chung et al. (2025), Fig. 12: Identification key of males, couplet 1. A: Typology IV, forewing of Adelomyrmex sp., illustration drawn from the image (CASENT0160764) of AntWeb (2023); AA: Typology I, forewing of Stegomyrmex connectens, illustration drawn from the image (CASENT0905914) of AntWeb (2023); AA: Typology II, forewing of Unicumyrmex, illustration newly drawn in this study; AA: Typology III, forewing of Monomorium chinense, illustration newly drawn in this study. Abbreviations: SMC submarginal cell.

2

return to couplet #1

• Frontal lobes developed, covering antennal insertions (Fig. 13A). Mandible with 7 teeth (Fig. 13B). Forewing venation of Typology I, with two submarginal cells (SMC) (Fig. 13C) => Stegomyrmex
• Frontal lobe undeveloped, the antennal insertions were only partially covered or exposed (Fig. 13AA). Mandible less than 7 teeth (Fig.13BB). Forewing venation of Typology II or III, with one submarginal cell (Fig. 13CC) => 3

• 

  Chung et al. (2025), Fig. 13: Identification key of males, couplet 2. A, B, head of Stegomyrmex connectens, illustration drawn from the image (CASENT0905914) of AntWeb (2023); C: Typology I, forewing of Stegomyrmex connectens, illustration drawn from the image (CASENT0905914) of AntWeb (2023); AA, BB, head of Rogeria sp., illustration drawn from the image (UFV-LABE-COL-007310) of AntWeb (2023); CC: Typology II, forewing of Unicumyrmex, illustration newly drawn in this study; CC: Typology III, forewing of Monomorium chinense, illustration newly drawn in this study. Abbreviations: SMC submarginal cell.

3

return to couplet #2

• Forewing venation of Typology II, with discal cell 1 (DC1) present (Fig. 14A) => 4
• Forewing venation of Typology III, with discal cell 1 absent (Fig. 14AA) => 14

• 

  Chung et al. (2025), Fig. 14: Identification key of males, couplet 3. A: Typology II, forewing of Unicumyrmex, illustration newly drawn in this study; AA: Typology III, forewing of Monomorium chinense, illustration newly drawn in this study. Abbreviations: DC1 discal cell 1.

4

return to couplet #3

• “Formica type” of forewing venation: Medial (M) and Radial sector (Rs) veins with an intersection point, which connects a short 2rs-m vein or 2r-rs vein if 2rs-m absent (Fig. 15A) => 5
• “Solenopsis type” of forewing venation: Medial and Radial sector veins separated by a long and distinct 2rs-m vein and therefore without an intersection point (Fig. 15AA) => 7

• 

  Chung et al. (2025), Fig. 15: Identification key of males, couplet 4. A forewing of Erromyrma latinodis, illustration drawn from the image (CASENT0788835) of Ramamonjisoa & al. (2023); AA forewing of Solenopsis geminata, illustration newly drawn in this study. Abbreviations: M medial vein; Rs radial sector vein; 2r-rs second radial-radial sector cross-vein; 2rs-m second radial sector-medial cross-vein.

5

return to couplet #4

• Mandible without teeth (Fig. 16A). Petiole and postpetiole both clavate in lateral view, long and without distinct node-shape, postpetiole longer than high (Fig. 16B) => Myrmicaria
• Mandible with 3 - 4 teeth (Fig. 16AA). Petiole and postpetiole not clavate in lateral view, petiole with distinct peduncle and node structure, postpetiole as long as high (Fig. 16BB) => 6

• 

  Chung et al. (2025), Fig. 16: Identification key of males, couplet 5. A, head of Myrmicaria arachnoides latinoda, illustration drawn from the image (FOCOL1598) of AntWeb (2023); B, petiole and postpetiole in lateral view of Myrmicaria arachnoides latinoda, illustration drawn from the image (FOCOL1598) of AntWeb (2023); AA, head of Epelysidris brocha, illustration drawn from the image of Ito & Yamane (2014); BB, petiole and postpetiole in lateral view of Epelysidris brocha, illustration drawn from the image of Ito & Yamane (2014).

6

return to couplet #5

• Head triangular (Fig. 17A), smooth and shiny. Antennal pedicel subglobular and enlarged, twice the width of other segments (Fig. 17B). Mandible with 4 teeth (Fig. 17C) => Erromyrma
• Head rounded (Fig. 17AA), covered with dense sculpture. Antennal pedicel more cylindrical, the same width as other segments (Fig. 17BB). Mandible with 3 teeth (Fig. 17CC) => Epelysidris

• 

  Chung et al. (2025), Fig. 17: Identification key of males, couplet 6. A, B, C, head of Erromyrma latinodis, illustration drawn from the image (CASENT0788835) of Ramamonjisoa & al. (2023); AA, BB, CC, head of Epelysidris brocha, illustration drawn from the image of Ito & Yamane (2014).

7

return to couplet #4

• Antennal scape long, exceeding lateral margin of compound eyes (Fig. 18A) => 8
• Antennal scape short, not exceeding lateral margin of compound eyes (Fig. 18AA) => 9

• 

  Chung et al. (2025), Fig. 18: Identification key of males, couplet 7. A, head of Dolopomyrmex pilatus, illustration drawn from the image (CASENT0178566) of AntWeb (2023); AA, head of Solenopsis geminata, illustration newly drawn in this study.

8

return to couplet #7

• Antenna with 11 segments. Petiole and postpetiole with lateral spine (Fig. 19A) => Dolopomyrmex
• Antenna with 13 segments. Petiole and postpetiole without lateral spine (Fig. 19AA) => Rogeria

• 

  Chung et al. (2025), Fig. 19: Identification key of males, couplet 8. A, petiole and postpetiole in dorsal view of Dolopomyrmex pilatus', illustration redrawn from the original publication (Cover & Deyrup 2007); AA, petiole and postpetiole in dorsal view of Rogeria sp., illustration drawn from the image (UFV-LABECOL-007310) of AntWeb (2023).

9

return to couplet #7

• Head triangular in full-face view => 10
• Head rectangular or rounded in full-face view => 11

10

return to couplet #9

• Antenna with 12 segments. Antennal insertion adjacent to each other (Fig. 20A). Mandible with 1 - 2 teeth (Fig. 20B). Palp formula 2,2 (Fig. 20C) => Unicumyrmex
• Antenna with 12 or 13 segments. Antennal insertion apart from each other (Fig. 20AA). Mandible with 1 - 4 teeth (Fig. 20BB). Palp formula 1,2 (Fig. 20CC) => Solenopsis

• 

  Chung et al. (2025), Fig. 20: Identification key of males, couplet 10. A, B, head of Unicumyrmex, illustration newly drawn in this study; C, maxilla and labium of Unicumyrmex, illustration newly drawn in this study; AA, BB, head of Solenopsis molesta, illustration drawn from the image (CASENT0007774) of AntWeb (2023); CC, maxilla and labium of Solenopsis, illustration drawn according to Pitts & al. (2018). Abbreviations: Lip labial palp; Mxp maxillary palp.

11

return to couplet #9

• Head rectangular. Mandible elongate-triangular (Fig. 21A). Propodeum slope rounded (Fig. 21B) => 12
• Head rounded. Mandible triangular (Fig. 21AA). Propodeum bluntly angulate (Fig. 21BB) => 13

• 

  Chung et al. (2025), Fig. 21: Identification key of males, couplet 11. A, head of Anillomyrma decamera (Emery, 1901), illustration newly drawn in this study, specimen from S. Yamane (TH18-SKY-262); B, mesosoma in lateral view of Anillomyrma decamera, illustration newly drawn in this study, specimen from S. Yamane (TH18-SKY-262); AA, head of Chelaner antarcticus, illustration drawn from the image (CASENT0172352) of AntWeb (2023); BB, mesosoma in lateral view of Chelaner antarcticus, illustration drawn from the image (CASENT0172352) of AntWeb (2023).

12

return to couplet #11

• Palp formula 4,3 (Fig. 22A). Antenna with 13 segments => Anillomyrma
• Palp formula 2,2 (Fig. 22AA). Antenna with 12 or 13 segments => Bondroitia

• 

  Chung et al. (2025), Fig. 22: Identification key of males, couplet 12. A, maxilla and labium of Anillomyrma decamera, illustration drawn according to Yamane & Jaitrong (2019); AA, maxilla and labium of Bondroitia, illustration drawn according to Bolton (1987). Abbreviations: Lip labial palp; Mxp maxillary palp.

13

return to couplet #11

• Mesoscutum parapsidal line present and distinct (Fig. 23A) => Chelaner
• Mesoscutum parapsidal line present but very faint (Fig. 23AA) => Oxyepoecus

• 

  Chung et al. (2025), Fig. 23: Identification key of males, couplet 13. A, mesosoma in dorsal view of Chelaner antarcticus, illustration drawn from the image (CASENT0172352) of AntWeb (2023); AA, mesosoma in dorsal view of Oxyepoecus, illustration drawn according to Kempf (1974).

14

return to couplet #3

• Mandible with 3 - 4 teeth (Fig. 24A). Palp formula 1,1 or 2,2. Subpetiolar process present (Fig. 24B) => Monomorium (in part)
• Mandible with a single apical tooth (Fig. 24AA). Palp formula 1,2. Subpetiolar process absent (Fig. 24BB) => Tropidomyrmex

• 

  Chung et al. (2025), Fig. 24: Identification key of males, couplet 14. A, head of Monomorium chinense, illustration newly drawn in this study; B, petiole and postpetiole in lateral view of Monomorium chinense, illustration newly drawn in this study; AA, head of Tropidomyrmex elianae, illustration drawn from the image (CASENT0189192) of AntWeb (2023); BB, petiole and postpetiole in lateral view of Tropidomyrmex elianae, illustration drawn from the image (CASENT0189192) of AntWeb (2023).

References

• Chung, F.-Y., Hsu, P.-W., Hsu, F.-C., Lin, C.-C. 2025. A new genus in a hyperdiverse ant lineage (Hymenoptera: Formicidae: Myrmicinae) revealed by integration of morphological and molecular evidence. Myrmecological News 35: 29-60 (doi:10.25849/MYRMECOL.NEWS_035:029).