Abstract
The fossil record of true aquatic bugs (Heteroptera: Nepomorpha) in amber outcrops is scarce, hampering our knowledge of their diversification. Recently, numerous discoveries have been made in mid-Cretaceous Kachin amber, whereas there is only one taxon described in Cenozoic ambers (Popov & Heiss, 2014), despite the abundance of such specimens in lacustrine deposits. We report the first reliable fossil occurrence of Micronectidae, which is tentatively attributed to the extant genus Micronecta. The taxonomic affinities of the fossil are discussed, as well as the scarcity of Nepomorpha in Cenozoic amber deposits.
References
- Bachofen-Echt, A. (1949) Der Bernstein und seine Einschlüsse. Springer-Verlag, Wien, 204 pp.
- Bode, A. (1953) Die Insektenfauna des Ostniedersächsischen oberen Lias. Palaeontographica, (A), 103, 1–375.
- Boderau, M., Fu, Y., Jiang, H., Guan, S., Peng, A., Nel, A. & Jouault, C. (2025a) Bayesian modelling of the fossil record enlightens the evolutionary history of Hemiptera. Proceedings of the Royal Society B, 292, 20251133. https://doi.org/10.1098/rspb.2025.1133
- Boderau, M., Nel, A., Maksoud, S., Abi-Saad, P. & Azar, D. (2025b) The first aquatic insect fossil from the Cenomanian Konservat-Lagerstätte of Haqel (Lebanon) fills a gap in the fossil record of giant water bugs (Heteroptera: Belostomatidae). Zootaxa, 5562 (1), 11–22. https://doi.org/10.11646/zootaxa.5562.1.4
- Criscione, J. & Grimaldi, D. (2017) The oldest predaceous water bugs (Insecta, Heteroptera, Belostomatidae), with implications for paleolimnology of the Triassic Cow Branch Formation. Journal of Palaeontology, 91, 1166–1177. http:// doi.org/10.1017/jpa.2017.48
- Criscione-Vastano, J. & Grimaldi, D. (2025) New hemipteran insects (Hylicellidae, Ipsviciidae, Heteroptera) from the Triassic Cow Branch Formation of Virginia and North Carolina, US. Journal of Palaeontology, 98, 1024–1040. http:// doi.org/10.1017/jpa.2024.52
- Engel, M.S., Grimaldi, D.A. & Krishna, K. (2007) A synopsis of Baltic amber termites (Isoptera). Stuttgarter Beiträge zur Naturkunde, (B), 372, 1–20.
- Grimaldi, D.A. & Engel, M.S. (2005) Evolution of the insects. Cambridge University Press, xv + 755 pp.
- Hebsgaard, M.B., Andersen, N.M. & Damgaard, J. (2004) Phylogeny of the true bugs (Nepomorpha: Hemiptera-Heteroptera) based on 16S and 28S rDNA and morphology. Systematic Entomology, 29, 488–508. https://doi.org/10.1111/j.0307-6970.2004.00254.x
- Jaczewski, T.L. (1924) Revision of the Polish Corixidae. Annales Zoologici Musei Polonici Historiae Nationalis, 3, 1–98.
- Kirkaldy, G.W. (1897) Synonymic notes on aquatic Rhynchota. The Entomologist, 30, 258–260.
- Labandeira, C.C. & Sepkoski, J.J. (1993) Insect diversity in the fossil record. Science, 261, 310–315. https://doi.org/10.1126/science.11536548
- Labandeira, C.C. (2014) Amber. In: LaFlamme, M., Schiffbauer, J.D. & Darroch, S.A.F. (Eds), Reading and Writing of the Fossil Record: Preservational Pathways to Exceptional Fossilization. Paleontological Society Papers, 20, 163–215.
- Latreille, P.A. (1810) Histoire naturelle, générale et particulière des Crustacés et des Insectes. Ouvrage faisant suite aux œuvres de Leclerc de Buffon et partie du cours complet d’Histoire naturelle rédigé par C.S. Sonnini. T. 13, an XIII. Familles naturelles et genres. Paris, Dufart,432 pp.
- Leach, W.E. (1815) Entomology. In: Brewster, D. (Ed.), The Edinburgh Encyclopaedia, Edimburgh, Blackwood, 9, 57–172.
- Limaye, A. (2012) Drishti, a volume exploration and presentation tool. Proceedings Volume 8506, Developments in X-Ray Tomography VIII; 85060X. https://doi.org/10.1117/12.935640
- Linnaeus, C. von (1758) Systema Naturae per regna tria naturae secundum classes, ordines, genera, species cum characteribus, differentiis, synonymis, locis. Ed. decima reformata. Holmiae, Laur. Salvii, Typis Ioannis Thomae nob. De Trattnern, Vindobonae, 1, 823 pp.
- Maksoud, S., Azar, D., Granier, B. & Gèze, R. (2017) New data on the age of the Lower Cretaceous amber outcrops of Lebanon. Palaeoworld, 26, 331–338. https://doi.org/10.1016/j.palwor.2016.03.003
- Nel, A. & Paicheler, J.C. (1992) Les Heteroptera aquatiques fossiles, état actuel des connaissances (Heteroptera: Nepomorpha et Gerromorpha). Entomologica Gallica, 3, 159–182.
- Nieser, N. & Chen, P.P. (2006) Two new genera and a new subfamily of Micronectidae (Heteroptera, Nepomorpha) from Brazil. Denisia, 19, 523−534.
- Poinar, G.O.Jr. & Brown, A.E. (2016) Toad bugs (Hemiptera: Gelastocoridae) in Myanmar amber. Cretaceous Research, 63, 39–44. https://doi.org/10.1016/j.cretres.2016.02.013
- Popov, Y.A. (1971) Istoričeskoe razvitie polužestkokrylych infraotrjada Nepomorpha (Heteroptera) [Historical development of Hemiptera of the infraorder Nepomorpha (Heteroptera)]. Trudy Paleontologicheskogo Instituta Akademii nauk SSSR, 129, 3–227.
- Popov, Y.A. (1992) Jurassic bugs (Hemiptera, Heteroptera) from the Museum of Natural History in Vienna. Annales Naturhistorisches Museum Wien, (A), 94, 7–14.
- Popov, Y.A. & Heiss, E. (2014) Riegerochterus baehri gen. nov. and spec. nov., the first fossil velvety bug (Hemiptera: Heteroptera, Ochteridae) from Dominican Amber. Andrias, 20, 185–190
- Schachat, S. & Labandeira, C.C. (2021) Are insects heading toward their first mass extinction? Distinguishing turnover from crises in their fossil record. Annals of the Entomological Society of America, 114, 99–118. https://doi.org/10.1093/aesa/saaa042
- Schuh, R.T. & Weirauch, C. (2020) True bugs of the world (Hemiptera: Heteroptera): classification and natural history [Second Edition]. Siri Scientific Press, Manchester, 800 pp.
- Shcherbakov, D.E. (2010) The earliest true bugs and aphids from the Middle Triassic of France (Hemiptera). Russian Entomological Journal, 19, 179–182. http://doi.org/10.15298/rusentj.19.3.04
- Sinitshenkova, N.D. (2003) Main ecological events in aquatic insect history. Acta Zoologica Cracoviensia, 46 (suppl. – Fossil Insects), 381–392.
- Solórzano Kraemer, M.M. Delclòs, X., Clapham, M.E., Arillo, A. & Peris, D. (2018) Arthropods in modern resins reveal if amber accurately recorded forest arthropod communities. Proceedings of the National Academy of Sciences, 115, 6739–6744. https://doi.org/10.1073/pnas.1802138115
- Streito J.-C. & Germain, J-F. (2020) Chapitre 23: Ordre des Hemiptera (Hémiptères). In: Aberlenc, H.-P. (Ed.), Les insectes du monde: biodiversité, classification, clés de détermination des familles. Museo Editions, Editions Quae, pp. 481–574.
- Tinerella, P.P. (2008) Taxonomic revision and systematics of New Guinea and Oceania pygmy water boatmen (Hemiptera: Heteroptera: Corixoidea: Micronectidae). Zootaxa, 1797 (1), 1–66. http://doi.org/10.11646/zootaxa.1797.1.1
- Tinerella, P.P. (2013) Taxonomic revision and systematics of continental Australian pygmy water boatmen (Hemiptera: Heteroptera: Corixoidea: Micronectidae). Zootaxa, 3623 (1), 1–121. http://doi.org/10.11646/zootaxa.3623.1.1
- Wichard, W., Grohn, C. & Seredszus, F. (2009) Wasserinsekten im Baltischen Bernstein. Verlag Kessel, Remagen-Oberwinter, Germany, 335 pp.
- Wichard, W. & Weitschat, W. (1996) Wasserinsekten im Bernstein. Eine paläobiologische Studie. Entomologische Mitteilungen aus dem Löbbecke Museum + Aquazoo, 4, 1–122.
- Xian, C., Damgaard, J., Luo, J., Chen, P., Xie, J., Wu, Y., Xie, Q. & Wang, Y. (2025) Serial amber fossils unveiling the innovation process of mouthparts in water boatmen (Hemiptera: Corixoidea) in the phylogenetic context of total evidence. Insect Systematics and Diversity, 9 (5), ixaf040. https://doi.org/10.1093/isd/ixaf040
- Xie, B., Chen, P., Damgaard, J., Xie, J., Xie, Q. & Wang, Y. (2024) Paraphyly of the subgenus Micronecta (Micronecta) Kirkaldy, 1897 (Hemiptera: Heteroptera: Micronectidae) based on mitochondrial genomes and nuclear rDNAs. Arthropod Systematics & Phylogeny, 82, 77–87. https://doi.org/10.3897/asp.82.e108906
- Ye, Z., Damgaard, J., Yang, H., Hebsgaard, M.B., Weir, T. & Bu, W. (2020) Phylogeny and diversification of the true water bugs (Insecta: Hemiptera: Heteroptera: Nepomorpha). Cladistics, 36, 72–87.
- Ye, Z., Damgaard, J., Hädicke, C.W., Zhu, X., Mazzucconi, S.A., Hebsgaard, M.B., Xie, T., Yang, H. & Bu, W. (2023) Phylogeny and historical biogeography of the water boatmen (Insecta: Hemiptera: Heteroptera: Nepomorpha: Corixoidea). Molecular Phylogenetics and Evolution, 180, 1–12. https://doi.org/10.1016/j.ympev.2022.107698
- Zhang, M., Zhao, Z., Ren, D. & Yao, Y. (2022) Three new species of velvety shore bugs (Hemiptera: Heteroptera: Ochteroidea) From Mid-Cretaceous Kachin amber shed light on the evolution of rostrum length in Ochteroidea. Frontiers in Ecology and Evolution, 10, 892530. https://doi.org/10.3389/fevo.2022.892530
