 |
| Douglassarachne acanthopoda Selden & Dunlop, 2024 DOI: 10.1017/jpa.2024.13 |
Abstract
A new genus and species of arachnid (Chelicerata: Arachnida), Douglassarachne acanthopoda n. gen. n. sp., is described from the late Carboniferous (Moscovian) Coal Measures of the Mazon Creek Lagerstätte, Illinois, USA. This is a unique animal with distinctive large spines on the legs. It has a subovate body, a segmented opisthosoma, and a terminal anal tubercle. The legs are robust and appear to have been similar in construction throughout the limb series, with heavy spination of the preserved proximal podomeres. The mouthparts and coxo-sternal region are equivocal. The preserved character combination does not permit easy referral to any known arachnid order, living or extinct, thus the new fossil in placed as Arachnida/Pantetrapulmonata incertae sedis. It contributes to an emerging pattern of disparate body plans among late Carboniferous arachnids, ranging from anatomically modern members of living orders through to extinct taxa, such as the present fossil, whose phylogenetic position remains unresolved.
 |
| Douglassarachne acanthopoda n. gen. n. sp., holotype and only known specimen FMNH PE 91366. (1) Photograph of part; (2) explanatory drawing of part; (3) photograph of counterpart; (4) explanatory drawing of counterpart; 1–4 = leg numbers; a t = anal tubercle; e t = eye tubercle; fe = femur; t = tergite. Scale bars = 5 mm. |
 |
| Douglassarachne acanthopoda n. gen. n. sp., reconstruction of the possible appearance of the animal in life. |
Systematic paleontology
Class Arachnida Lamarck, Reference Lamarck, 1801
Pantetrapulmonata incertae sedis
Genus Douglassarachne new genus
Type species: Douglassarachne acanthopoda new species, by monotypy.
The genus is named for the Douglass family who kindly donated the specimen to the Field Museum for study.
Douglassarachne acanthopoda new species
Diagnosis: Relatively large arachnid (body length >15 mm) with median dorsal ocular tubercle on carapace, abdominal tergites, anal tubercle, legs bearing many long, curved macrospines.
Etymology: From the Greek αγκάθι, a thorn or prickle, and πόδι, leg, with reference to the very spiny legs of this animal.
Paul A. Selden and Jason A. Dunlop. 2024. A remarkable Spiny Arachnid from the Pennsylvanian Mazon Creek Lagerstätte, Illinois. Journal of Paleontology. DOI: doi.org/10.1017/jpa.2024.13
Non-technical Summary: The forests of the late Carboniferous period (about 300–320 million years ago) harbored a great variety of arachnids. In addition to the familiar spiders, harvestmen, and scorpions, there were other, stranger kinds of spider-like animals. Here, we describe a large spider-like arachnid with very spiny legs (presumably to deter predators), from the world-famous Mazon Creek fossil localities of Illinois, USA.
