Epimetopidae

Fikáček, Martin, Matsumoto, Keita, Perkins, Philip, Prokin, Alexander, Sazhnev, Alexey, Litovkin, Stanislav & Jäch, Manfred A., 2021, The family Epimetopidae (Coleoptera: Hydrophiloidea): review of current knowledge, genus-level phylogeny, and taxonomic revision of Eupotemus, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 61 (1), pp. 1-34 : 16

Key to genera of Epimetopidae

1. Elytra with scutellary stria, odd intervals with series of elevated tubercles, never with keels ( Fig. 15 ). Pronotum without longitudinal keels ( Fig. 14 ). Aedeagus with very long curved conical phallobase and complex multilobate parameres ( Figs 6V–Z ). Male sternite IX O-shaped ( Fig. 6U ). Asia. ..................................... .............................. Eumetopus Balfour-Browne, 1949

– Elytra without scutellary stria, odd intervals with longitudinal keels which may be interrupted here and there ( Figs 9 , 10 , 12 , 16 ). Pronotum with longitudinal keels ( Figs 9 , 10 , 12 , 16 ). Aedeagus with simple flat open phallobase and simple parameres ( Figs 6D–H, L–R ). Male sternite IX U- or V-shaped ( Figs 6C, K ). Africa and America. .................................................... 2

2. Procoxal cavities open posteriorly ( Fig. 3A ). Male sternite IX V-shaped ( Fig. 6C ). Median lobe with a single ventral projection which is simple or bifid at apex ( Figs 6G–H ). Africa. .............................................. ........................................... Eupotemus Ji & Jäch, 1998

– Procoxal cavities closed posteriorly ( Figs 3G, I ). Male sternite IX U-shaped ( Fig. 6K ). Median lobe either without any projections, or with a pair of projections ( Figs 6L–R ). America. .................................................... ...................................... Epimetopus Lacordaire, 1854

Figures

Fig. 15. Elytral sculpture and male genitalia of Eumetopus Balfour-Browne, 1949. A–H – elytral sculpture, same specimens as in Fig. 14: A – E. acutimontis Ji & Jäch, 1998; B – E. asperatus (Champion, 1919); C – E. bullatus (Sharp, 1875); D – E. flavidulus (Sharp, 1890); E – E. maindroni (Régimbart, 1903); F – E. schuelkei Jäch, 2002; G – E. tibialis Ji & Jäch, 1998; H – E. weigeli Skale & Jäch, 2003. I–L – male genitalia of examined specimens, large basal portion of the phallobase omitted (dorsal and lateral view): I – E. acutimontis from Vietnam; J – E. flavidulus from India: Andhra Pradesh; K – E. maindroni from India: Gujarat; L – E. weigeli from India: Uttarakhand.

Fig. 14. Habitus photographs of the known species of Eumetopus Balfour-Browne, 1949. A – E. acutimontis Ji & Jäch, 1998, paratype from China: Hainan (NHMW); B – E. asperatus (Champion, 1919), specimen from Nepal: Koshi Valley (NMPC); C – E. bullatus (Sharp, 1875), specimen from India: Maharashtra, Sawantwadi (NMPC); D – E. flavidulus (Sharp, 1890), specimen from India: Meghalaya, Bagmara (NHMW); E – E. maindroni (Régimbart, 1903), specimen from India: Maharashtra, Sawantwadi (NHMW); F – E. schuelkei Jäch, 2002, paratype from central Laos; G – E. tibialis Ji & Jäch, 1998 from Thailand, Ban Na env. (NMPC); H – E. weigeli Skale & Jäch, 2003, holotype from Nepal (NHMW). Scale bars: 1 mm.

Fig. 6. Male genitalia and associated structures of Epimetopidae. A–H – Eupotemus Ji & Jäch, 1998 (A–F – E. smithi sp. nov.; G – E. cameroonensis sp. nov.; H – E. carinaticollis (Basilewsky, 1956)). I–R – Epimetopus Lacordaire, 1854 (I–N – E. mendeli Fikáček et al., 2011; O – E. cf. burruyacu Oliva, 1986; P – E. multiporus Perkins, 2012; Q – E. clandestinus Perkins, 2012; R – E. thermarum Schwarz & Barber, 1917). S–Z – Eumetopus Balfour-Browne, 1949 (S–Y – E. acutimontis Ji & Jäch, 1998; Z – E. bullatus (Sharp, 1875)).A, I, S – sternite VIII; B, J, T – tergite VIII; C, K, U – sternite IX; D, L, V – aedeagus dorsally; E, M, W – aedeagus laterally; F, N, X – aedeagus ventrally (basal part omitted in X); Y – sperm pump. Color coding: green – ventral projections of the median lobe; red – median lobe; blue – paramere (pale blue – dorsal lobe; dark blue – ventral lobe). Not to scale.

Fig. 9. Habitus photographs of the species of the Eupotemus limicola species group, holotypes: A–C – E. bilobatus sp. nov.; D–F – E. cameroonensis sp. nov.; G–I – E. limicola (Delève, 1967).

Fig. 10. Habitus photographs of the species of the Eupotemus limicola species group, holotypes (A–F) and differences between species groups in pronotal morphology (G–H). A–C – E. smithi sp. nov.; D–F – E. ophioglossus sp. nov.; G–I – pronotal sculpture: G – E. carinaticollis species group; H – E. limicola species group.

Fig. 12. Habitus photographs of the species of the Eupotemus carinaticollis species group, holotypes: A–C – E. carinaticollis (Basilewsky, 1956); D–F – E. uluguru sp. nov.; G–I – E. taianus sp. nov.

Fig. 16. Photographs of Epimetopus species, including two specimens of questionable provenance (E–G).A – E. flavicaptus Fikáček, Barclay & Perkins, 2011; B – E. deceptus Perkins, 2012; C – E. tridens Perkins, 2012; D – E. hintoni Balfour-Browne, 1949; E – Epimetopus sp. (ʻZambiaʼ); F–G – E. cf. burruyacu Oliva, 1986 (ʻSaudi Arabiaʼ) (F – dorsal view; G – aedeagus). Scale bars for A–F = 0.5 mm. A–D adopted from Pൾ*©κංඇඌ (2012).

Fig. 3. Thoracic morphology of the genera of Epimetopidae. A–B, J, Q – Eupotemus smithi sp. nov.; C–D, L–O – Eumetopus schuelkei Jäch, 2002; E–F – Epimetopus mendeli Fikáček, Barclay & Perkins, 2012; G–I, P – Epimetopus costaricensis Perkins, 1979. A–I – prothorax in ventral view (B, D, F, H – detail of ventral sculpture of the pronotal hood; I – detail of closed procoxal cavity. J–L – meso- and metathorax in ventral view. M–N – elytron in ventral view (M – general view; N – detail of the ventral ridge, notice the spiny surface on inner face of the ridge (in) and on the elytral plectrum posteriorly of it (pl)). O – mesotrochanter. P–Q – details of pretarsus with the leaf-like empodial seta. Not to scale.