Monday, March 23, 2026

[Paleontology • 2026] Balticolasma wunderlichi • 3D analyses of the First ortholasmatine Harvestmen (Opiliones: Nemastomatidae) from European Eocene Ambers

 

Balticolasma wunderlichi 
Bartel, Mitov, Dunlop & Hammel, 2026

Artistic reconstruction by Joshua Knüppe  x.com/JoschuaKnuppe




The first fossil representatives of the harvestman subfamily Ortholasmatinae (Opiliones, Dyspnoi, Nemastomatidae) are described as Balticolasma wunderlichi gen. et sp. nov. One male is preserved in Eocene Baltic amber and a presumably conspecific female in Eocene Rovno amber (northwest Ukraine). Ortholasmatines are typically highly ornate arachnids, and for the first time with an amber harvestman we applied computed tomography using synchrotron radiation to investigate its three-dimensional morphology and surface structure in considerable detail. Some of its morphological characters, appear to be closer to extant Asian genera. In a wider biogeographic context, our amber record is a significant find for the Paleogene of Europe given that (i) it is another species apparently found in both Baltic and Rovno amber and (ii) all modern ortholasmatines are restricted to East Asia and North and Central America.

Key words: Nemastomatidae, Ortholasmatinae, Baltic amber, Rovno amber, micro-CT, Priabonian, Eocene

Ortholasmatine harvestman Balticolasma wunderlichi gen. et sp. nov. paratype (female) MB.A.4455 from Rovno amber, 33.90–37.71 Ma, Priabonian.
A1, dorsal view of the body A2, close-up of the ocular process in dorsal view, eye lenses arrowed.
Abbreviations: cp, carapace process; ey, eye lens; oc, ocular process; legs numbered I–IV. Scale bars 1 mm (A1) and 0.5 mm (A2).

Artistic reconstruction of the Eocene ortholasmatine harvestman Balticolasma wunderlichi gen. et sp. nov. (male) by Joshua Knüppe (Ibbenbüren, Germany).

Systematic palaeontology 
Order Opiliones Sundevall, 1833 
Suborder Dyspnoi Hansen & Sørensen, 1904 
Family Nemastomatidae Simon, 1872 
Subfamily Ortholasmatinae Shear & Gruber, 1983 
Genus Balticolasma nov.

Balticolasma wunderlichi gen. et sp. nov. 

Etymology: From the Baltic region where the amber hosting one of the specimens originates from and the suffix lasma applied to a few possibly closely related modern ortholasmatine genera.



Christian Bartel, Plamen G. Mitov, Jason A. Dunlop, and Jörg U. Hammel. 2026. 3D analyses of the First ortholasmatine Harvestmen from European Eocene Ambers. Acta Palaeontologica Polonica. 71(1): 95-107. DOI: doi.org/10.4202/app.01283.2025