A new species and a new record of Zoicinae Lehtinen & Hippa, 1979 (Araneae: Lycosidae) from Sumatra Island, with notes on miniaturization in wolf spiders

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  A new species and a new record of Zoicinae Lehtinen & Hippa, 1979 (Araneae: Lycosidae) from Sumatra Island, with notes on miniaturization in wolf spiders Abstract A new species of wolf spider, Zoica veloxilla sp. nov., from Sumatra (Indonesia) is described based on both sexes. Lysania pygmaea Thorell, 1890 is recorded from Sumatra for the first time, and its male is illustrated and redescribed. A distribution map for Zoica and Lysania is provided. The problem of miniaturization in wolf spiders is briefly discussed. Based on an analysis of the literature, 32 minute species of wolf spiders in four subfamilies and eleven genera have been reported. The smallest wolf spider known worldwide seems to be Zoica minuta (McKay, 1979) from Australia. Omelko, M.M. & Fomichev, A.A. (2026) A new species and a new record of Zoicinae Lehtinen & Hippa, 1979 (Araneae: Lycosidae) from Sumatra Island, with notes on miniaturization in wolf spiders. Zootaxa, 5869 (2), 339–350. https://doi.o...

Batesian Mimicry Converges Towards Inaccuracy in Myrmecomorphic Spiders

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Batesian Mimicry Converges Towards Inaccuracy in Myrmecomorphic Spiders

Abstract

Batesian mimicry is an impressive example of convergent evolution driven by predation. However, the observation that many mimics only superficially resemble their models despite strong selective pressures is an apparent paradox. Here, we tested the ‘perfecting hypothesis’, that posits that inaccurate mimicry may represent a transitional stage at the macro-evolutionary scale by performing the hereto largest phylogenetic analysis (in terms of the number of taxa and genetic data) of ant-mimicking spiders across two speciose but independent clades, the jumping spider tribe Myrmarachnini (Salticidae) and the sac spider sub-family Castianeirinae (Corinnidae). We found that accurate ant mimicry evolved in a gradual process in both clades, by an integration of compound traits contributing to the ant-like habitus with each trait evolving at different speeds. Accurate states were highly unstable at the macro-evolutionary scale likely because strong expression of some of these traits comes with high fitness costs. Instead, the inferred global optimum of mimicry expression was at an inaccurate state. This result reverses the onus of explanation from inaccurate mimicry to explaining the exceptional evolution and maintenance of accurate mimicry and highlights that the evolution of Batesian mimicry is ruled by multiple conflicting selective pressures.

Kelly, M. B., Derkarabetian, S., McLean, D. J., Shofner, R., Grismado, C. J., Haddad, C. R., Cassis, G., Giribet, G., Herberstein, M. E., & Wolff, J. O. Batesian Mimicry Converges Towards Inaccuracy in Myrmecomorphic Spiders. Systematic Biology. https://doi.org/10.1093/sysbio/syaf037