Anelosimus studiosus

Agnarsson, Ingi, 2006, A revision of the New World eximius lineage of Anelosimus (Araneae, Theridiidae) and a phylogenetic analysis using worldwide exemplars, Zoological Journal of the Linnean Society 146 (4), pp. 453-593: 471

publication ID 10.1111/j.1096-3642.2006.00213.x

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Anelosimus studiosus



F. O. P.- Cambridge (1902) described a variable and widespread A. studiosus   , but commented that the variation could indicate several similar species (see quote at beginning of this chapter). Levi (1956) agreed with F. O. P.- Cambridge’s (1902) previously suggested synonymies, and added Enoplognatha dubia   and A. fraternus   . The species thus became even more variable and widespread, from Argentina to northeastern United States (e.g. Washington, DC), and from a wide range of altitudes (0–4000 m) and habitats (e.g. tropical forest, temperate scrub). In a section called ‘subspecies’ Levi (1956: 419) commented on, and illustrated, the considerable geographical variation in size and genitalic, especially palpal, morphology of his A. studiosus   . Given the complexity of Anelosimus   taxonomy, and virtual absence of behavioural data, Levi understandably preferred to treat all these taxa as one species. However, in addition to differences in morphology, recent studies indicate differences in behaviour (including different levels of sociality) and barriers to breeding (failed breeding experiments) between several geographically separated populations ( Brach, 1977; Furey, 1998; Jones & Parker, 2002; L. Avilés, pers. comm.). With access to much more material, and armed with new behavioural observations, it seems now that Levi’s (1956) A. studiosus   is rather a species complex, including at least eight species. The studiosus   group (see Fig. 59 View Figure 59 , clade 5) is here supported by two unambiguous synapomorphies: closely arranged sclerotized copulatory ducts (10 -1, Fig. 44D View Figure 44 ), and a snout-like Eb (75 -1, Figs 44A, F View Figure 44 , 49B, H, K, L View Figure 49 ).