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1. Feeding behaviour of generalist and specialist predators is determined by a variety of trophic adaptations. Specialised prey‐capture adaptations allow specialists to catch relatively large prey on a regular basis. As a result, specialists might be adapted to exploit each item of prey more thoroughly than do generalists. 2. It was expected that obligatory specialist cursorial spiders would feed less frequently than generalists but for a longer time and, thus, that their foraging pause would be longer. First, the feeding frequencies of three generalist spider species (Cybaeodamus taim, Harpactea hombergi, Hersiliola sternbergsi) were compared with those three phylogenetically related specialist species: myrmecophagous Zodarion rubidum, and araneophagous Nops aff. variabilis and Palpimanus orientalis. 3. Generalists captured more prey, exploited each item of prey for a significantly shorter time, and had a shorter foraging pause than was the case for specialists. Generalists also gained significantly less relative amount of prey mass than did specialists. 4. Second, the study compared the prey DNA degradation rate in the gut of generalists and specialists by means of PCR. The degradation rate was not significantly different between specialists and generalists: the detectability half‐life was estimated to exist for 14.3 days after feeding. 5. This study shows that the feeding strategies of cursorial generalist and obligatory specialist spiders are different. Obligatory specialists have evolved a feeding strategy that is based on thorough exploitation of a few large prey, whereas generalists have evolved a strategy that is based on short exploitation of multiple small items of prey. The feeding frequency and prey consumption of specialist and generalist spiders were compared.This study shows that the feeding strategies of cursorial generalist and obligatory specialist spiders are different.Specialists thoroughly exploited a few large prey, whereas generalists have evolved a strategy that is based on short exploitation of multiple small items of prey. [ABSTRACT FROM AUTHOR]

Populations of many taxa are polymorphic as a result of interactions between different evolutionary processes. One such taxon is the salticid spider genus Myrmarachne, which is under strong selection for myrmecomorphy resulting in an accurate mimetic resemblance to various ant species. In revising eastern Australian Myrmarachne, we provide descriptions of four new species (Myrmarachne helensmithae sp. nov., Myrmarachne macaulayi sp. nov., Myrmarachne milledgei sp. nov., and Myrmarachne zabkai sp. nov.) and redescriptions of seven species [Myrmarachne bicolor (L. Koch, 1879), Myrmarachne erythrocephala (L. Koch, 1879), Myrmarachne luctuosa (L. Koch, 1879), Myrmarachne lupata (L. Koch, 1879), Myrmarachne macleayana (Bradley, 1876), Myrmarachne smaragdina Ceccarelli, 2010, and Myrmarachne striatipes (L. Koch, 1879)]. Myrmarachne jugularis Simon, 1900 is a junior synonym of M. macleayana; Myrmarachne cognata (L. Koch, 1879) and Myrmarachne simoni (L. Koch, 1879) are synonyms of M. luctuosa; Myrmarachne rubra Ceccarelli, 2010 is a junior synonym of M. bicolor; and Myrmarachne cuprea (Hogg, 1896) is considered nomen dubium. In a few species (M. erythrocephala, M. luctuosa, M. macleayana, M. milledgei sp. nov., and M. striatipes) we recognized at least two (discrete) forms that differ only in colour pattern. Our phylogenetic analysis supports the existence of species groups and forms, but contradicts the designation of some species. At present we find the eastern Australian fauna is thus composed of 11 Myrmarachne species, five of which have forms. [ABSTRACT FROM AUTHOR]