Neoichnology of tarantulas (Araneae: Theraphosidae): Criteria for recognizing spider burrows in the fossil record

Palaeontologia Electronica

Daniel I. Hembree¹ 

[1] Hembree. Department of Geological Sciences, Ohio University, 316 Clippinger Laboratories, Athens, Ohio 45701, USA.

关键词: ichnofossils;    trace fossils;    continental;    arthropod;    arachnid;    paleoecology;   

学科分类：地质学

来源: Palaeontologia Electronica

【 摘 要 】

The Mygalomorphae, a suborder of heavy bodied spiders that includes tarantulas, first appears in the Triassic. While burrowing is common among extant mygalomorphs, fossil burrows attributable to this group are not well-documented. The goal of this study is to describe the morphology of tarantula burrows and to compare them to the burrows of other large, terrestrial animals with the purpose of improving the interpretation of continental ichnofossils and ancient soil ecosystems. This project involved the study of the burrowing behaviors and burrow morphologies of Hysterocrates gigas, Pelinobius muticus, and Aphonopelma chalcodes (Araneae: Theraphosidae), which inhabit tropical to subtropical forests, scrublands and grasslands, and semi-arid deserts, respectively. Individual tarantulas were placed in sediment-filled terrariums under controlled temperature and moisture conditions according to their environmental preferences. The tarantulas were observed for three to 12 months after which they were removed, and the open burrows were cast with plaster, excavated, and described. Each species constructed burrows by excavating sediment using their chelicerae and pedipalps. Burrow openings were circular to elliptical and lined with thin layers of silk. The tarantulas produced burrows with distinct morphologies: 1) H. gigas: vertical shafts with elongate ovoid chambers near the sediment surface and at depth, 2) P. muticus: subvertical sinuous shafts with and without branches, and 3) A. chalcodes: straight to curved, subhorizontal tunnels. Tarantula burrows as a group were also distinct from burrows of trapdoor spiders, scorpions, salamanders, and skinks. Data collected from these neoichnological studies can be applied to continental ichnofossil assemblages in order to better interpret the paleoecology of ancient soil ecosystems.

【 授权许可】

CC BY