Amaurobius

Abstract: A new species, Amaurobius koponeni sp. n., is described from Himachal Pradesh on the basis of a male specimen. A key to all five genera of Amaurobiidae that occur in Asia is provided. Four species from India and Nepal incorrectly assigned to Amaurobius are transferred to three genera of Titanoecidae: Anuvinda milloti (Hubert, 1973), comb. n., Pandava andhraca (Patel & Reddy, 1990), comb. n., Pandava nathabhaii (Patel & Patel, 1975), comb. n., and Titanoeca sharmai (Bastawade, 2008), comb. n.

Abstract: This group of spiders, here designated as the bennetti group of Amaurobius , comprises those North American species which group around Amaurobius bennetti (Blackwall). In these species, the epigynum has a pair of large lateral lobes which converge posteriorly around a small ovoid median lobe. The male has three distinct spurs on the tibia of the palpus, at the distal end above. The more detailed characteristics of this group are as follows:

Abstract: Brood caring behavior was observed in Amaurobius ferox (Araneae, Amaurobiidae), a semelparous subsocial spider, from cocoon construction until the emergence of spiderlings from the cocoon. Unlike most spiders, which emerge from cocoon by their own means, A. ferox mothers intervene in the process of the emergence of their young. I manipulated broods by removing the mother prior to emergence to determine the effects of maternal behavior on the emergence of spiderlings. My results showed that maternal intervention making the cocoon expansion and its exit, is not absolutely necessary for the emergence of A. ferox spiderlings from the cocoon. Nine clutches out of ten were able to get out of the cocoon by their own means without their mother`s help. There was no difference between control groups (`with mother`) and experimental groups (`without mother`) in the number of spiderlings that emerged ( vs. , respectfully) and in the time from the beginning to the end of emergence ( vs. hours). Time from eclosion until the emergence of the first individual in a clutch, however, was greater in the mother-absent group (3.5 days) than in the control group (2.0 days). The construction of the cocoon by the mother required always occurred in the same area within the retreat, and took approximately 6 hours, and the mother guarded the eggs during the incubation period. The emergence of the spiderlings followed a sigmoidal pattern. After emergence, the spiderlings formed a very compact group on the cocoon, which may be important in securing maternal care. The absence of cribellum and calamistrum, structures likely involved in their survival, observed in individuals of the first instar suggests that in the first stage of life, the spiderlings are dependent on their mother.

Abstract: A collection of amaurobiid spiders from the Western Mediterranean region is analysed. Callobius theoblickisp. n. is newly described from north Portugal. Amaurobius barbarus Simon, 1911, from Algeria and Spain, and A. cerberusFage, 1931, from the south of Spain, are redescribed or newly illustrated. Amaurobius erberi is recorded for the first time in Algeria. Amaurobius minorcaBarrientos & Febrer, 2018, until now only known from Menorca, is cited also in Majorca and in continental Spain.