Working group
Dunlop
The evolution of fossil arachnids and other chelicerates
Research
Our research focuses on fossil arachnids and their relatives. The main focus is on the evolutionary history of this group of animals. We analyse when and where groups such as spiders, scorpions, harvestmen and ticks first appeared, and how they are related to one another.
To this end, we examine fossils, including those from the collection of the Museum für Naturkunde Berlin, and compare them with living species. Extinct arachnids provide additional information on the distribution and evolutionary success of this group.
Key areas
The origins of spiders
With more than 50,000 living species, spiders are among the most successful groups of animals. Fossils date back over 300 million years to the Carboniferous period.
We are investigating early spider-like forms that provide clues to the group’s origins. One example is Chimerarachne, a fossilised spider with a tail that was discovered in Burmese amber dating back around 100 million years. Such finds enable us to reconstruct early branches in the spider family tree.
The oldest ticks
Ticks are important parasites that feed on the blood of vertebrates and can transmit numerous diseases. Fossil ticks are rare, but finds from Burmese amber provide new insights into their early evolution.
The amber contains both extinct and extant genera, including the oldest known representatives of Amblyomma and Haemaphysalis. The fossil species Khimaira fossus combines characteristics of hard-shelled and soft-shelled ticks and could represent a link between the two main groups.
Orthoptera in amber
Orthoptera are highly diverse today, but rarely occur as fossils. Many aspects of their evolution and distribution are therefore still poorly understood.
We are studying fossil harvestmen from various amber deposits, such as Baltic, Bitterfeld and Burmese amber. Using micro-CT, we analyse their morphology and describe new species. The results allow us to draw conclusions about their phylogenetic history and their former distribution across the continents.
People
Dr Jason Dunlop
PI
Email: Jason.Dunlop@mfn.berlin
Publications
Dunlop, J.A., Erdek, M., Bartel, C. (2023). A new species of camel spider (Arachnida: Solifugae) in Baltic amber. Arachnology, 19(4), 772-776. DOI: https://doi.org/10.13156/arac.2023.19.4.772
Dunlop, J., Bartel, C. (2025). A new species of fossil Phrynus Lamarck, 1801, from Dominican Republic amber (Amblypygi: Phrynidae). Zootaxa, 5563(1), 64-72. DOI: https://doi.org/10.11646/zootaxa.5563.1.7
Dunlop, J.A., Garwood, R.J. (2023). The status of two fossils assigned to the scorpion genus Palaeophonus and its interpretation as a senior synonym of Allopalaeophonus. Arachnology, 19(6), 940-943. DOI: https://doi.org/10.13156/arac.2023.19.6.940
Dunlop, J.A., Wellman, C.H., Prendini, L., Shear, W.A. (2023). A pectinal tooth with peg sensilla from an Early Devonian scorpion. The Journal of Arachnology, 51(3). DOI: https://doi.org/10.1636/JoA-S-22-024
æ Bisong, P.T., Dunlop, J., Madruga, C. (2023). Mammalian type material from Cameroon in the Museum für Naturkunde Berlin. Zoosystematics and Evolution, 99(2), 503-517. DOI: https://doi.org/10.3897/zse.99.110878
æ Dunlop, J.A. (2023). The first Palaeozoic spider (Arachnida: Araneae) from Germany. PalZ, 97(3), 497-504. DOI: https://doi.org/10.1007/s12542-023-00657-7
æ Dunlop, J.A., Dernov, V.S. (2023). The first trigonotarbid arachnid from Ukraine. Acta Geologica Polonica, 181-187. DOI: https://doi.org/10.24425/agp.2022.143600
æ Dunlop, J.A., Garwood, R.J. (2024). A review of fossil scorpion higher systematics. PeerJ, 12, e18557. DOI: https://doi.org/10.7717/peerj.18557
æ Bartel, C., Dunlop, J.A., Wedmann, S. (2024). Iridescent harvestmen (Arachnida: Opiliones: Sclerosomatidae) from the Eocene of Messel, Germany. Palaeobiodiversity and Palaeoenvironments, 104(4), 963-975. DOI: https://doi.org/10.1007/s12549-024-00607-4
æ Chitimia-Dobler, L., Handschuh, S., Dunlop, J.A., Pienaar, R., Mans, B.J. (2024). Nuttalliellidae in Burmese amber: implications for tick evolution. Parasitology, 151(9), 891-907. DOI: https://doi.org/10.1017/S0031182024000477
æ Cianferoni, F., Dunlop, J.A., Ceccolini, F. (2023). Atypus affinis Eichwald, 1830 in Tuscany. Quaderno di Studi e Notizie di Storia Naturale della Romagna, 57, 145-150. URL: http://www.ssnr.it/57-7.pdf
æ Garwood, R.J., Dunlop, J.A. (2023). Consensus and conflict in studies of chelicerate fossils and phylogeny. Arachnologische Mitteilungen: Arachnology Letters, 66(1). DOI: https://doi.org/10.30963/aramit6602
æ Garwood, R.J., Dunlop, J.A. (2023). X-ray microtomography of the late Carboniferous whip scorpions (Arachnida, Thelyphonida) Geralinura britannica and Proschizomus petrunkevitchi. Journal of Systematic Palaeontology, 21(1), 2180450. DOI: https://doi.org/10.1080/14772019.2023.2180450
æ Knecht, R.J., Benner, J.S., Swain, A., Azevedo-Schmidt, L., Cleal, C.J., Labandeira, C.C., Engel, M.S., Dunlop, J.A., Selden, P.A., Eble, C.F., Renczkowski, M.D., Wheeler, D.A., Funderburk, M.M., Emma, S.L., Knoll, A.H., Pierce, N.E. (2024). Early Pennsylvanian Lagerstätte reveals a diverse ecosystem on a subhumid, alluvial fan. Nature Communications, 15(1), 7876. DOI: https://doi.org/10.1038/s41467-024-52181-0
æ Santos, A.A., Dunlop, J.A., Hernández-Orúe, A., Selden, P.A., Diez, J.B., McLoughlin, S. (2025). Trigonotarbids (Arachnida) hidden in plant debris from a Late Pennsylvanian tropical forest at El Bierzo, Castilla y León, Spain. PalZ, 99(4), 567-580. DOI: https://doi.org/10.1007/s12542-025-00745-w
æ Selden, P.A., Dunlop, J.A. (2024). A remarkable spiny arachnid from the Pennsylvanian Mazon Creek Lagerstätte, Illinois. Journal of Paleontology, 98(3), 395-401. DOI: https://doi.org/10.1017/jpa.2024.13
æ Siyam, M., Dunlop, J.A., Kovařík, F., Mohammad, A. (2023). Additions to the distribution of Sudanese scorpions. Zoosystematics and Evolution, 99(1), 45-53. DOI: https://doi.org/10.3897/zse.99.90875
æ Šlapeta, J., Halliday, B., Dunlop, J.A., Nachum-Biala, Y., Salant, H., Ghodrati, S., Modrý, D., Harrus, S. (2023). The “southeastern Europe” lineage of the brown dog tick Rhipicephalus sanguineus (sensu lato) identified as Rhipicephalus rutilus Koch, 1844: Comparison with holotype and generation of mitogenome reference from Israel. Current Research in Parasitology & Vector-Borne Diseases, 3, 100118. DOI: https://doi.org/10.1016/j.crpvbd.2023.100118
æ Wu, Z., Dunlop, J., Klimov, P., Mai, H., Peng, A., Liu, Y. (2025). A new whip scorpion (Arachnida: Thelyphonida) with a phoretic mite (Acariformes: Trochometridiidae) from Mid-Cretaceous Kachin amber. BMC Ecology and Evolution, 25. DOI: https://doi.org/10.1186/s12862-025-02392-w
Bartel, C., Dunlop, J.A. (2023). First eupnoid harvestmen (Arachnida: Opiliones: Eupnoi) from mid-Cretaceous Kachin amber, with notes on sexual dimorphism in Halitherses grimaldii (Arachnida: Opiliones: Dyspnoi). Palaeoentomology, 6(3). DOI: https://doi.org/10.11646/palaeoentomology.6.3.11
Bartel, C., Dunlop, J.A., Giribet, G. (2023). An unexpected diversity of Cyphophthalmi (Arachnida: Opiliones) in Upper Cretaceous Burmese amber. Zootaxa, 5296(3), 421-445. DOI: https://doi.org/10.11646/zootaxa.5296.3.6
Bartel, C., Dunlop, J.A., Sharma, P.P., Selden, P.A., Tarasov, P.E., Ren, D., Shih, C. (2023). Four new Laniatorean harvestmen (Arachnida: Opiliones) from mid-Cretaceous Burmese amber. Palaeoworld, 32(1), 124-135. DOI: https://doi.org/10.1016/j.palwor.2022.06.006
Bicknell, R.D.C., Dunlop, J., Young, A., Lauer, B., Lauer, R., McCoy, V.E. (2025). Unique, dimple-like exoskeletal structures suggest syn-vivo infestations in Late Carboniferous horseshoe crabs. Biology Letters, 21(12), 20250565. DOI: https://doi.org/10.1098/rsbl.2025.0565
Chitimia-Dobler, L., Pfeffer, T., Würzinger, F., Handschuh, S., Dunlop, J.A. (2023). New larval records of the extinct hard tick Compluriscutula vetulum (Arachnida: Ixodida) from Burmese amber, with notes on its morphology. Palaeoworld, 33(5), 1327-1335. DOI: https://doi.org/10.1016/j.palwor.2023.10.002
Knecht, R.J., Benner, J.S., Dunlop, J.A., Renczkowski, M.D. (2023). The largest Palaeozoic whip scorpion and the smallest (Arachnida: Uropygi: Thelyphonida); a new species and a new ichnospecies from the Carboniferous of New England, USA. Zoological Journal of the Linnean Society, 200(3), 690-704. DOI: https://doi.org/10.1093/zoolinnean/zlad088
Sherwood, D., Cobo, S.A., Dunlop, J.A., Tsavalas, A.T., Geci, D., Lucas, S.M., Brescovit, A.D. (2025). Reidentification of historical specimens assigned to Cupiennius oculifer (Karsch, 1879) (Araneae: Trechaleidae). Zootaxa, 5723(1), 138-142. DOI: https://doi.org/10.11646/zootaxa.5723.1.8
Sherwood, D., Dunlop, J., Sharp, A. (2024). On the identity of Opopaea euphorbicola Strand, 1909 and first records of three other non-native goblin spiders from Ascension Island (Araneae: Oonopidae). Zootaxa, 5437(1), 125-130. DOI: https://doi.org/10.11646/zootaxa.5437.1.9
Wang, H., Lei, X.J., Luo, C.H., Dunlop, J.A. (2023). First jumping spider (Araneae: Salticidae) from mid-Miocene Zhangpu amber. Palaeoworld, 32(4), 716-720. DOI: https://doi.org/10.1016/j.palwor.2022.06.002
