There and back again: More on the taxonomy of the crab spiders genus Epicadus (Thomisidae: Stephanopinae)

Abstract

The Neotropical crab spider genera Tobias Simon, 1895 and Epicadus Simon, 1895 comprise species with remarkable somatic morphology and confounding taxonomic history. The results of our recent cladistic analysis corroborate and extend preceding taxonomic assumptions in showing that Tobias is a junior synonym of Epicadus. In the present paper the six species recently transferred from Tobias to Epicadus are redescribed. Two new species are described based on both males and females: Epicadus dimidiaster sp. nov. and Epicadus tigrinus sp. nov.; the male of Epicadus granulatus Banks, 1909 is described for the first time. The diagnosis of the genus is revised, an identification key is provided, and information on geographical distribution is updated. Epicadus now comprises eleven species.

First record of Epicadus trituberculatus (Taczanowski, 1872) (Araneae, Thomisidae, Stephanopinae) in the Brazilian Northeast

“…Identification. According to the diagnosis of Machado et al (2018), females of E. trituberculatus have a somewhat similar morphology with E. camelinus. However, they can be distinguished by the coloration pattern, as E. trituberculatus presents the anterior tibiae and femora of the first and second pair of legs entirely yellow while E. camelinus has large brown stains on the first and second pair of legs.…”

“…Of the six specimens observed we collected manually only three to preserve as voucher material. The identification of the individuals was made based on the identification key of Machado et al (2018). Individuals were photographed on the field using the camera Canon 6D.…”

“…The family Thomisidae is the seventh largest family of spiders, currently comprising 170 genera and 2163 species (World Spider Catalog 2019). They present worldwide distribution with most of their species occurring in tropical or subtropical regions (Machado et al 2018;World Spider Catalog 2019). These spiders are diurnal sit-and-wait predators that are often found in vegetation, mainly on flowers or leaves.…”

“…These spiders are diurnal sit-and-wait predators that are often found in vegetation, mainly on flowers or leaves. Some species are cryptically colored and are able to change their coloration to camouflage themselves in their environment, such as (Machado et al 2017(Machado et al , 2018. Epicadus species can be recognized by their globose opisthosoma with a set of conical projections and a median spire on the fovea region; for more details, see Silva-Moreira and Machado (2016) and Machado et al (2018).…”

“…Some species are cryptically colored and are able to change their coloration to camouflage themselves in their environment, such as (Machado et al 2017(Machado et al , 2018. Epicadus species can be recognized by their globose opisthosoma with a set of conical projections and a median spire on the fovea region; for more details, see Silva-Moreira and Machado (2016) and Machado et al (2018). Epicadus individuals reflect light in the ultraviolet (UV) wavelength range of the spectrum and manipulate the UV signals of flowers, which these spiders to attract and ambush pollinators (Vieira et al 2017).…”