Araneusbonali sp. n., a novel lichen-patterned species found on oak trunks (Araneae, Araneidae)

Zookeys. 2018 Aug 7:(779):119-145. doi: 10.3897/zookeys.779.26944. eCollection 2018.

Abstract

The new species Araneusbonali Morano, sp. n. (Araneae, Araneidae) collected in central and western Spain is described and illustrated. Its novel status is confirmed after a thorough revision of the literature and museum material from the Mediterranean Basin. The taxonomy of Araneus is complicated, but both morphological and molecular data supported the genus membership of Araneusbonali Morano, sp. n. Additionally, the species uniqueness was confirmed by sequencing the barcode gene cytochrome oxidase I from the new species and comparing it with the barcodes available for species of Araneus. A molecular phylogeny, based on nuclear and mitochondrial genes, retrieved a clade with a moderate support that grouped Araneusdiadematus Clerck, 1757 with another eleven species, but neither included Araneusbonali sp. n. nor Araneusangulatus Clerck, 1757, although definitive conclusions about the relationships among Araneus species need more markers examined and a broader taxonomic coverage. The new species was collected on isolated holm oaks and forest patches within agricultural landscapes. Adults were mostly trapped on tree trunks, where their lichen-like colours favour mimicry, while juveniles were collected on tree branches. Specimens were never found either in ground traps or grass samples. This species overwinters as egg, juveniles appear in early spring, but reproduction does not take place until late summer-early autumn. Araneusbonali Morano, sp. n. was found in the same locality from where another new spider species was described. Nature management policies should thus preserve isolated trees as key refuges for forest arthropods in agricultural landscapes, as they may be hosting more unnoticed new species. After including Araneusbonali Morano, sp. n. and removing doubtful records and synonymies, the list of Araneus species in the Iberian Peninsula numbers eight.

Keywords: Quercus ilex; DNA barcoding; Iberian Peninsula; isolated trees; mimicry; molecular phylogeny.