Notes on spiders of the family Salticida^. Ir^.1 o J. . *jj ^ 2 6nAS.i7o7 . 1 he genera bpart aeus, Mintonia and; Taraxi F. R. Wanless Department of Zoology, British Museum (Natural History), "X^ ^ffAl Hl^> ' &^ I Synopsis The genus Taraxella is redefined to include those spartaeines in which the embolus of the male palp is largely obscured by tegular apophyses. The male of Spartaeus thailandica Wanless and the female of Mintonia melinauensis Wanless are described for the first time. One new species of Spartaeus, two new species of Mintonia and four new species of Taraxella are described from the Oriental Region. Diagnoses and figures are provided. The presence of mytiliform organs on the legs and filamentous metatarsal leg fringes are described for the first time. They are illustrated, together with femoral organs, muscle attachment sites and apophyses by scanning electron micrographs. Introduction The purpose of the present paper is to describe seven new species and the previously unknown male and female of two described species belonging in the subfamily Spartaeinae. The subfamily is of particular interest because some species spin large webs that are used to capture prey. Typical salticids are cursorial hunters with good vision that do not spin webs to capture prey, although they will spin silk nests in which to lay eggs, moult and sometimes mate, and generally rest at night or during other periods of inactivity (Jackson, 1979). The first reports of web-spinning in jumping spiders (Coleman, 1978, 1980; Murphy, in Wanless, 19786) were followed by several important studies (Jackson & Blest, 1982; Jackson, 1982; Jackson & Hallas, in press a) that confirmed the phenomenon and provided a rare insight into the biology of a small group of tropical salticids. These spiders all belonged in the old world genus, Portia Karsch, that is presently classified along with 12 other genera in the subfamily Spartaeinae. In addition to building large prey-capture webs, Portia species will leave their web and stalk prey as cursorial hunters i.e. in the same manner as other salticids. Furthermore, they may invade the webs of other spiders and feed on trapped insects (kleptoparasitism), the resident spider, or even its eggs (oophagy). In life they resemble tatty mouldy leaves or detritus, their ornate hair tufts and fringes (Fig. 3) providing a form of camouflage that enables them to stalk prey without being noticed, an important guise since they show a marked preference for other spiders, including salticids. Portia species are also 'aggressive vibratory mimics' for when they invade other spider webs they pluck the threads and deceive the owner into accepting Portia as potential prey only to be attacked themselves on approaching within jumping distance. Occurrence of the unusual behaviour patterns of Portia species correlate to some degree in this and related spartaeines by the presence of morphological structures that are not known to occur in other spiders. These include femoral organs (Figs 5E; 14A) and pore-bearing apophyses (Figs 9E arrowed; 20 A, B) both of which are especially evident in some of the species described below. Also present on the legs of one species (Spartaeus wildtrackii sp. n.) are mytiliform organs (Fig. 15A-C; 16A, B), structures that have hitherto only been found grouped together as a discrete patch on the dorsal surface of the abdomen (Fig. 20C) of species ofCyrba Simon, Portia, Gelotia Thorell, and Mintonia Wanless. The function of these structures is unknown but previous studies (Wanless, 1984a, b; 1985) have suggested that they may be associated with pheromone dispersal. Jackson & Hallas (in press b} have demonstrated that sex pheromones are involved in mate recognition in some Portia, Brettus Thorell and Cyrba, thus supporting earlier work by Legendre and Llinares, Bull. Br. Mus. not. Hist. (Zool.) 52(3): 107-137 Issued 26 March 1987 107
BioStor
