Mastinocerinae

Uchima-Taborda, Diego, Hortúa, Andrés Lugo De La, Vega-Badillo, Viridiana, Fernández, Fernando & Zaragoza-Caballero, Santiago, 2025, Platysognathus gen. nov. a new genus of railroad-worm beetle (Coleoptera: Phengodidae, Mastinocerinae) from Colombian Amazonía, Zootaxa 5636 (3), pp. 577-586 : 583

Key for the identification of the Mastinocerinae genera with 11-segmented antenna

Adapted from Vega-Badillo et al. 2023 and Zaragoza-Caballero & Pérez-Hernández 2014.

4 Antennae 11 segmented................................................................................ 5

5 Interantennal distance longer than scape length............................................................. 6

5’ Interantennal distance subequal to or less than scape length.................................................. 6b

6 Antennal flabellae cylindrical, ventral tarsal combs present on first and second protarsomeres and first mesotarsomere....................................................................... Microphrixothrix Roza & Mermudes 2019

6’ Antennal flabellae lanceolated, ventral tarsal combs present only on first pro– and mesotarsomere.................... 6a

6a Mandible simple, without any tooth. Antennal flabellae of antennomeres IV–X fully developed..... Euryopa Gorham, 1881

6a’ Mandible with a conspicuous tooth on its inner border, antennal flabellae variable................................ 6*

6* Mandibular tooth rhomboid, antennal flabellae on antennomeres IX–X fused to its correspondent antennomere, which gives to these antennomeres the appearance of being inflated and without rami.................... Euryognathus Wittmer, 1976

6*’ Mandibular tooth irregularly rhomboid with a medial acute projection ( Fig. 2A ), flabellae on antennomeres IX–X fully developed....................................................................... Platysognathus gen. nov.

6b All tarsomeres without ventral combs................................................ Steneuryopa Wittmer, 1986

6b’ Tarsal combs present only in the first protarsomere.......................................................... 7

7 Mandibles projected and not crossed, pointed forward obliquely from head............ Cleidella Roza & Mermudes 2020

7’ Mandibles not projected forward and crossed.................................... Halffterus Vega-Badillo et.al. 2023

Figures

FIGURE 2. Platysognathus amazonicus gen. et sp. nov. A–D, F–J Holotype, E Paratype. A. Right mandible dorsal view; B. Maxillary and labial palps ventral view; C. Protarsus; D. Mesotarsus; E. Elytra in dorsal view; F. Posterior wing; G. Aedeagus dorsal view; H. Aedeagus right lateral view; I. Aedeagus left lateral view; J. Apex of genital flagellum.