Palaeothele montceauensis

Overview

Palaeothele montceauensis is a Late Carboniferous spider studied for visible segmentation of its abdomen. The front body and abdomen connect through a narrow junction. Ancient, different features can be found within the familiar broad divisions of a spider’s body.^[1]

Key facts

The type specimen preserves the front body, narrow junction, abdomen, and connections of appendages near the body. Researchers also compared abdominal tergites in an additional specimen regarded as probably belonging to the same species. Different fossils reveal different body regions.^[1]

Time and place

It was described in a 1996 study addressing Late Carboniferous fossils. The Carboniferous as a whole was roughly 360–300 million years ago. Its name then was Eothele montceauensis, using a different genus from the currently registered name.^[1][2]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

A narrow junction lies between the front body and abdomen, and segmentation is visible on the abdomen. An additional specimen compared on the assumption of belonging to the same species is described as having an oval carapace and at least eight abdominal tergites. Major body divisions can be examined alongside small repeating structures.^[1]

Palaeothele montceauensis preserves fossil spinnerets with basal diameters of 0.2–0.6mm. These structures, much smaller than the whole body, show that spiders already possessed silk-handling organs in the Carboniferous.^[3]

Habitat and reproduction

Comparisons of spider bodies examine the front body, abdomen, and the junction between them separately. The segmented abdomen of Palaeothele invites consideration of varied constructions among ancient spiders. This research moves beyond a single familiar appearance to compare features in each region.^[1]

Fossil discovery

Selden described this fossil under the name Eothele in 1996. The type specimen and additional specimen were used together in comparisons because different regions were visible in each. Following the history of names and the roles of specimens connects research on the same organism.^[1]

References

1. Selden (1996) — The first described fossil mesothelean spider
2. International Commission on Stratigraphy (2024) — Geological time chart
3. Garwood et al. (2016) — Almost a spider: a 305-million-year-old fossil arachnid and spider origins
4. Study — Microtomography of Eophrynus

Research questions

How can we judge whether different fossil fragments belong to the same species? This study compared preserved structures and explained the additional specimen under an assumption of conspecific assignment. We can examine which connections were proposed in the process of bringing complementary evidence together.^[1]

Observation

Move your gaze from the front body through the narrow junction to the large abdomen. Examining abdominal segments separately from appendage positions close to the body makes each region’s construction clearer.^[1]