Untangling the phylogenetic webs of orb‐weaving spiders

Study treating 90 per cent of named species in the family produces a globally representative revision of Araneid phylogeny

GBIF-mediated data resources used : 66,479 species occurrences
Macracantha arcuata
Macracantha arcuata observed in Gunung Mulu National Park, Malaysia. Photo 2019 Kal Squires via iNaturalist under (CC BY-NC 4.0)

The third-most speciose family of spiders, Araneidae (the orb-weaving spiders) has been widely studied from within various branches of research including behavioral science, ecology, material science, genomics and pharmacology. Modern phylogenetic revisions of the family, however, have been geographically limited.

Continuing previous work on Araneid evolution and diversification, the authors of this study present a new phylogeny, based on genetic samples from 158 taxa. Using GBIF-mediated occurrences they generate a map of the global distribution of Araneid species and add many understudied species from the southern hemisphere to get a true global representation of the family. Surprisingly, many clades named in the new phylogeny cannot be corroborated by current knowledge from morphological or behavioral studies.

Based on the phylogeny, the authors also analysed the evolution of sexual size dimorphism and web architecture. While genera exhibiting the former did not form a distinct clade, several patterns were discovered for web architecture including a monophyletic group of spanning thread web spiders.

Original article

Scharff N, Coddington JA, Blackledge TA, Agnarsson I, Framenau VW, Szűts T, Hayashi CY and Dimitrov D (2019) Phylogeny of the orb‐weaving spider family Araneidae (Araneae: Araneoidea). Cladistics. Wiley 36(1): 1–21. Available at: https://doi.org/10.1111/cla.12382