Eodromyia rovnoensis Shamshev, 2025

Shamshev, Igor V., Perkovsky, Evgeny E. & Legalov, Andrei A., 2025, A new species of hybotid dance fly of the genus Eodromyia (Diptera: Hybotidae, Tachydromiinae) from the late Eocene Rovno amber, Ecologica Montenegrina 81, pp. 14-21 : 15-21

Eodromyia rovnoensis Shamshev , sp. nov.

https://zoobank.org/ urn:lsid:zoobank.org:act:F5FECB43-9A7E-42A2-BABD-FA1D655F115B

( Figs 1 , 2 )

Type material. Holotype, female, SIZK UA- 27924, Rovno amber, Ukraine, late Eocene. The holotype is in a subrectangular light yellow stone (6x5x 2 mm); with a syninclusion: Palaeosystenus succinorum (Meunier, 1907) ( Diptera : Dolichopodidae ) ( Fig. 1A ). The specimen is complete, in good condition but its lower portion is covered with a dense, milky coating.

Diagnosis. Minute fly, body length about 1 mm; wing lacking cell bm (crossvein bm-m absent), vein R 4+5 straight; scutellum with 4 setae.

Description. Female ( Figs 1B, C ). Body length 1.2, wing length 1.1 mm. Head. Frons ( Fig. 1D ) broadly V-shaped, narrow above antennae, widened towards ocellar tubercle, greyish pruinose. Face linear, very narrow. Eyes rather narrow (lateral view), ommatidia uniformly large, with scattered ommatrichia. One pair of rather long, strong, lateroclinate, posterior ocellar setae inserted anterior to posterior ocelli; two lateroclinate setulae just behind ocellar triangle; two inclinate upper orbital setae present, nearly as long as ocellars (inserted slightly anterior to anterior ocellus). Two vertical setae, inclinate, nearly as long as ocellar setae. Occiput pruinose, with row of short postocular setae. Antenna with scape bearing mostly subequally short setulae, 1 seta beneath longer (nearly as long as length of pedicel); postpedicel about as long as pedicel, rather subglobular, somewhat asymmetrical, with small dorsoapical extension, probably bearing a sensory pit on inner face; stylus dorsoapical, arista-like, very long, nearly 6X longer than postpedicel, short pubescent. Gena, proboscis and palpi obscured; probably proboscis somewhat elongate, palpus small and bearing at least 1 subapical seta. Thorax ( Figs 1D , 2A ) Faintly tomentose; 1 moderately long, strong postpronotal seta (accompanied by some short setae anteriorly); prothoracic episterna with 1 setula just above fore coxa and 1 short upturned seta on upper part. Mesonotal setae: scutum covered with well differentiated, relatively sparse setae arranged in more or less distinct irregular rows (5–6 setae per row); acrostichal setae slightly shorter than dorsocentrals and barely separated from them; dorsocentral setae 2–3-serial, 1 longer prescutellar seta; 2 supra-alars, 3 notopleurals (2 setae longer), 1 postalar; scutellum broadly rounded, with 4 setae (apical pair long, lateral pair very short). Legs. Relatively slender but fore femur and tibia distinctly stouter; setulose, almost lacking prominent setae, mid femur with 1 moderately long, anterior subapical seta. Wing ( Fig. 2B ). Normally developed; membrane hyaline, covered with distinct microtrichia. Basal costal seta present, short. Costal index (proportions of distances between humeral crossvein and R 1 / R 1 and R 2+3 / R 2+3 and R 4+5, respectively): 1.5/1/2. R 1 meeting costa before midpoint of wing; Rs originating at about proximal 1/4 between humeral crossvein and apex of vein R 1, long, 4X longer than basal portion of R 4+5; R 2+3 meeting costa beyond midpoint of wing, nearly straight, gently curved meeting costa; R 4+5 and M 1 divergent towards wing margin, both straight. Crossvein r-m distinct, very short. Cell bm absent (crossvein bm-m absent). Cell cua absent, no trace of vein CuA+CuP. Anal lobe weakly prominent. Halter with dark knob contrasting with pale stem. Abdomen. Tergites rather well sclerotised ( Fig. 2C ), without visible setae or modifications; cercus short.

Male. Unknown.

Etymology. The epithet refers to the type locality of the new species.

Differential diagnosis. The new species differs from Eodromyia pumilio primarily by the wing venation. In E. rovnoensis sp. nov., vein R 1 is longer, meeting costa beyond apex of cell br ( Fig. 2B ). In E. pumilio , R 1 meets the costa before the apex of cell br ( Myskowiak et al., 2018: fig. 2A). In addition, E. rovnoensis sp. nov. has four scutellar setae (versus two in E. pumilio ).

Remarks. Palaeosystenus succinorum (Meunier, 1907) ( Diptera : Dolichopodidae ) is reported from Rovno amber for the first time (I.Ya. Grichanov, pers. comm.).

Discussion

The tribe Drapetidini includes fossil representatives of six genera (14 species) ( Solórzano Kraemer et al. 2005; Myskowiak et al. 2018; Greenwalt et al. 2019). However, Eodromyia is the only extinct genus of this group. In addition, Eodromyia is the oldest representative of the tribe because E. pumilio was described from the Lower Eocene Oise amber in France (Sparnacian, lower Ypresian, 53 Ma) ( Brasero et al., 2009; Myskowiak et al. 2018). Our record of the second species of Eodromyia from the upper Eocene Rovno amber suggests that this genus existed at least over the entire Eocene period and it had a relatively broad distribution.

The relationships of Eodromyia within Drapetidini are presently not evident. Eodromyia could probably be associated with the primitive genera Chaetodromia Chillcott and Austrodromia Collin because of the presence of the postpronotal lobe on the thorax (plesiomorphic state) ( Chillcott & Teskey 1983). In addition, like Austrodromia , both species of Eodromyia possess a pair of upper orbital setae. Austrodromia and Chaetodromia are known from the Neotropical Realm ( Chillcott & Teskey 1983; Cumming & Sinclair, 2009). Extant species (with one exception) of both genera are known from the mountains of Mexico and South America or south from Argentina and Chile, i.e. from the regions with mesothermal and microthermal climate ( Chillcott & Teskey 1983). One species of Chaetodromia was described from Mexican amber ( Solórzano Kraemer et al. 2005).

The climate of the Oise amber forest was paratropical ( Colombo et al. 2020), whereas the climate of the Rovno amber was equable (characterised by reduced thermal seasonity when compared with modern extra-tropical regions with similar MAT, see Archibald & Farrell 2003). Thus, we could conclude that the species of Eodromyia were cryophobic ( Archibald et al. 2023; Jenkins Shaw et al. 2024). The absence of this genus in Baltic amber may indicate that the climate of the Baltic amber forest was not warm enough for this group.

Eodromyia is the first plant or animal genus known only from Rovno and Oise ambers. However, this group is probably one of a number of cryophobic taxa of Rovno amber which are absent or poorly represented in Baltic amber (e.g., Baranov et al. 2016; Matalin et al. 2021; Anisyutkin et al. 2023; Belokobylskij et al. 2023; Nabozhenko & Perkovsky 2023; Chemyreva et al. 2024a, 2024b; Mamontov et al. 2024). They may be evidence of a warmer climate in the Rovno amber forest compared to the Baltic, along with physical and chemical data ( Mänd et al. 2018). Such taxa (depending on the group) are the main or very significant faunistic element that determines the differences between the Rovno and Baltic amber biotas ( Colombo et al. 2021; Melnitsky et al. 2024a, 2024b).

Acknowledgements

We are very grateful to Dmitry Vorontsov (Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia) for his help in preparation of the inclusion and photos. Igor Grichanov (All-Russian Institute of Plant Protection, St. Petersburg – Pushkin) kindly identified a syninclusion of Dolichopodidae . The study of Igor Shamshev was performed within the frames of the Russian State Research Project no. 122031100272-3 of the Ministry of Science and Higher Education of the Russian Federation. Patrick Grootaert (Royal Belgian Institute of Natural Sciences, Brussels, Belgium) and an anonymous reviewer kindly provided constructive comments and suggestions on an earlier draft of the manuscript.

References

Anisyutkin, L.N., Legalov, A.A. & Perkovsky, E.E. (2024) New species and new record of embiids (Insecta: Embiodea) from upper Eocene of Europa. Ecologica Montenegrina, 79, 16–28.

https://doi.org/10.37828/em.2024.79.3

Archibald, S.B. & Farrell, B.D. (2003) Wheeler’s dilemma. Acta Zoologica Cracoviensia, 46 (Supplement—Fossil Insects), 17–23.

Archibald, S.B., Mathewes, R.W. & Aase, A. (2023) Eocene giant ants, Arctic intercontinental dispersal, and hyperthermals revisited: discovery of fossil Titanomyrma (Hymenoptera: Formicidae: Formiciinae) in the cool uplands of British Columbia, Canada. The Canadian Entomologist, 155, e6. https://doi.org/10.4039/tce.2022.49

Baranov, V.A., Kvifte, G.M. & Perkovsky, E.E. (2016) Two new species of fossil Corethrella Coquillett from Late Eocene Rovno amber, with a species-level phylogeny for the family based on morphological traits (Diptera: Corethrellidae). Systematic Entomology, 41 (2), 531–540.

https://doi.org/10.1111/syen.12172

Belokobylskij, S.A., Simutnik, S.A., Vasilenko, D.V. & Perkovsky, E.E. (2023) First record of the parasitoid subfamily Doryctinae (Hymenoptera, Braconidae) in Rovno amber: description of a new genus and species with stigma-like enlargement on the hind wing of the male. Journal of Hymenoptera Research, 95, 59–72. https://doi.org/10.3897/jhr.95.96784

Brasero, N., Nel, A. & Michez, D. 2009. Insects from the Early Eocene amber of Oise (France): Diversity and palaeontological significance. Denisia, 26, 41–52.

Chemyreva, V.G., Legalov, A.A. & Perkovsky, E.E. (2024 a) A new genus of Ambositrinae (Hymenoptera, Diapriidae) from Rovno amber and remarks on the Eocene distribution of the subfamily. Ecologica Montenegrina, 79, 104–112. https://doi.org/10.37828/em.2024.79.9

Chemyreva, V.G., Vasilenko, D.V. & Perkovsky, E.E. (2024 b) ‘ Where there are many cattle’ in the Eocene of Ukraine: Review of Ambositra Masner (Hymenoptera, Diapriidae, Ambositrinae) from Rovno amber, with the description of three new species. Zootaxa, 5446 (4), 499–516.

https://doi.org/10.11646/zootaxa.5446.4.3

Chillcott, J.G. & Teskey, H.J. (1983) A revision of the New World genera allied to Megagrapha Melander (Diptera: Empididae). The Canadian Entomologist, 115, 1291–1328.

https://doi.org/10.4039/Ent1151291-10

Colombo, W.D., Perkovsky, E.E. & Azevedo, C.O. (2020) Phylogenetic overview of flat wasps (Hymenoptera, Bethylidae) reveals Elektroepyrinae, a new fossil subfamily. Palaeoentomology, 3 (3), 269–283. https://doi.org/10.11646/palaeoentomology.3.3.8

Colombo, W.D., Gobbi, F.T., Perkovsky, E.E. & Azevedo, C.O. (2021) Synopsis of the fossil Pristocerinae (Hymenoptera, Bethylidae), with description of two new genera and six species from Burmese, Taimyr, Baltic and Rovno ambers. Historical Biology, 33 (9), 1736–1752.

https://doi.org/10.1080/08912963.2020.1733551

Cumming, J.M. & Sinclair, B.J. (2009) Empididae (dance flies, balloon flies, predaceous flies). In: Brown, B.V., Borkent, A., Cumming, J.M., Wood, D.M., Woodley, N.E. & Zumbado, M.A. (Eds.), Manual of Central American Diptera. Volume 1. NRC Research Press, Ottawa, Ontario, Canada, pp. 653–670. http://dx.doi.org/10.4289/0013-8797-112.3.478

Cumming, J.M. & Wood, D.M. (2017) [Chapter] 3. Adult morphology and terminology. In: Kirk-Spriggs, A.H. & Sinclair, B.J. (Eds.), Manual of Afrotropical Diptera. Volume 1. Introductory chapters and keys to Diptera families. Suricata 4. South African National Biodiversity Institute, Pretoria, pp. 89–133.

Evenhuis, N.L. (2013) New microbombyliids (Diptera: Mythicomyiidae) from Eocene Baltic and Rovno ambers, with notes on previously described amber species, Zootaxa, 3731 (3), 371–380.

Greenwalt, D.E., Bickel, D.J., Kerr, P.H., Curler, G.R., Brown, B.V., de Jong, H., Fitzgerald, S.J., Dikow, T., Tkoč, M., Kehlmaier, C. & Amorim, D.S. (2019) Diptera of the middle Eocene Kishenehn Formation. I. Documentation of diversity at the family level. Palaeontologia Electronica, 22.2.50A, 1–56. https://doi.org/10.26879/891

Grichanov, I.Ya. (2000) Notes on Dolichopodidae (Diptera) from Ukrainian and Baltic amber. International Journal of Diptera Research, 11, 129–131.

https://doi.org/10.11646/zootaxa.5150.3.6

Grimaldi, D. & Cumming, J. (1999) Brachyceran Diptera in Cretaceous ambers and Mesozoic diversification of the Eremoneura. Bulletin of the American Museum of Natural History, 239, 1–124.

Grootaert, P. & Shamshev, I.V. (2012) The fast-running flies (Diptera, Hybotidae, Tachydromiinae) of Singapore and adjacent regions. European Journal of Taxonomy, 5, 1–162.

https://doi.org/10.5852/ejt.2012.5

Ivanov, V.D., Melnitsky, S.I. & Perkovsky, E.E. (2016) Caddisflies from Cenozoic resins of Europe. Paleontological Journal, 50 (5), 485–493. https://doi.org/10.1134/S0031030116050063

Jenkins Shaw, J., Perkovsky, E.E., Ślipiński, A., Escalona, H. & Solodovnikov, A. (2024) An extralimital fossil of the genus Diagrypnodes (Coleoptera: Salpingidae: Inopeplinae). Historical Biology, 36 (7), 1196–1203. https://doi.org/10.1080/08912963.2023.2206858

Mänd, K., Muehlenbachs, K., McKellar, R.C., Wolfe, A.P. & Konhauser, K. (2018) Distinct origins for Rovno and Baltic ambers: evidence from carbon and hydrogen stable isotopes. Palaeogeography, Palaeoclimatology, Palaeoecology, 505, 265–283.

https://doi.org/10.1016/j.palaeo.2018.06.004

Mamontov, Yu.S., Ignatov, M.S., Vasilenko, D.V. & Perkovsky, E.E. (2024) Hepatics from Rovno amber (Ukraine): Leptoscyphus davidii sp. nov. The Bryologist, 127 (1), 88–94.

https://doi.org/10.1639/0007-2745-127.1.088

Matalin, A.V., Perkovsky, E.E. & Vasilenko, D.V. (2021) First record of tiger beetles (Coleoptera, Cicindelidae) from Rovno amber with the description of a new genus and species. Zootaxa, 5027 (2), 290–296. https://doi.org/10.11646/zootaxa.5027.2.9

Melnitsky, S.I., Ivanov, V.D., Legalov, A.A. & Perkovsky, E.E. (2024 a) Palaeohelicopsyche netnetdaida sp. n., a first species of Helicopsychidae (Insecta: Trichoptera) from Eocene Rovno amber. Ecologica Montenegrina, 79, 118–124. https://doi.org/10.37828/em.2024.79.11

Melnitsky, S.I., Ivanov, V.D., Legalov, A.A., Vasilenko, D.V. & Perkovsky, E. E. (2024 b) The new species of Holocentropus, Plectrocnemia and Phryganea (Insecta: Trichoptera) from Eocene Rovno amber. Ecologica Montenegrina, 80, 1–12. https://doi.org/10.37828/em.2024.80.1

Myskowiak, J., Garrouste, R. & Nel, A. (2018) Eodromyia pumilio gen. et sp. nov., a new empidoid fly from the Earliest Eocene amber of France (Diptera: Hybotidae: Tachydromiinae). Zootaxa, 4379 (2), 279–286. https://doi.org/10.11646/zootaxa.4379.2.8

Nabozhenko, M.V. & Perkovsky, E.E. (2023) Oracula campbelli sp. n. – the first fossil darkling beetle (Coleoptera: Tenebrionidae: Alleculinae) from the late Eocene Rovno amber (Ukraine). Zootaxa, 5230 (2), 245–250. https://doi.org/10.11646/zootaxa.5230.2.8

Perkovskу, E.E., Mostovski, M.B. & Henderickx, H. (2015) New records of the dipteran genera Triphleba (Phoridae) and Prosphyracephala (Diopsidae) in Rovno and Baltic ambers. Vestnik zoologii, 49 (3), 245–250. https://doi.org/10.1515/vzoo-2015-0025

Perkovsky, E.E., Rasnitsyn, A.P., Vlaskin, A.P. & Taraschuk, M.V. (2007) A comparative analysis of Baltic and Rovno amber arthropod faunas: representative samples. African Invertebrates, 48 (1), 229–245.

Plant, A.R., Shamshev, I. & Perkovsky, E.E. (2012) A new species of Hemerodromia Meigen (Diptera: Empididae: Hemerodromiinae) from Late Eocene Rovno Amber. Studia dipterologica, 18 (2011), 79–84.

Shamshev, I.V. & Perkovsky, E.E. (2022) A review of fossil taxa of Microphorinae (Diptera, Dolichopodidae sensu lato), with redescription of the Eocene genus Meghyperiella Meunier. Zootaxa, 5150 (3), 411–427. https://doi.org/10.11646/zootaxa.5150.3.6

Shamshev, I.V., Vasilenko, D.V. & Perkovsky, E.E. (2025) A new genus of hybotid dance fly (Diptera: Hybotidae, Tachydromiinae) from the Eocene Sakhalinian amber. Zootaxa, in press.

Sinclair, B.J. & Cumming, J.M. (2017) Hybotidae (hybotid dance flies). In: Kirk-Spriggs, A.H. & Sinclair, B.J. (Eds.), Manual of Afrotropical Diptera. Vol. 2. Nematocerous Diptera and lower Brachycera. Suricata 5. SANBI Graphics & Editing, Pretoria, pp. 1237–1250.

Solórzano Kraemer, M.M., Sinclair, B.J. & Cumming, J.M. (2005) Five new species of Tachydromiinae (Diptera: Empididae s.l.) from New World Tertiary ambers. Zootaxa, 1010 (1), 37–52.

https://doi.org/10.11646/zootaxa.1010.1.4

Figures

Figure 1. Eodromyia rovnoensis sp. nov., female, holotype. A. Position of syninclusions in amber nodule. B. Habitus, dorsal view. C – same, lateral view. D – head and thorax, dorsal view. Abbreviations: a oc – anterior ocellus, ar styl – arista-like stylus, oc s – ocellar seta, p oc – posterior ocellus, ped – pedicel, pped – postpedicel, pprn lb – postpronotal lobe, u orb s – upper orbital seta, vrt s – vertical seta.

Figure 2. Eodromyia rovnoensis sp. nov., female, holotype. A. Head and thorax, lateral view. B. Wing, outline. C. Apical part of abdomen, lateral view. Abbreviations: br – basal radial cell; C – costal vein; cerc – cercus; M1 – first branch of media; M4 – fourth branch of media; R1 – anterior branch of radius; R2+3 – second branch of radius; R4+5 – third branch of radius; r-m – radial-medial crossvein; Rs – radial sector. Scale bar refers to A, B and C.