A comparative morphology of trichobothrial bases in araneoid spiders and its significance for the phylogeny and system of the superfamily Araneoidea (Arachnida, Araneae).

Bothrial morphology was studied by SEM in 137 araneoid genera representing all 22 currently recognized extant families and all 42 conventional subfamilies of the Araneoidea. The ancestral type in the superfamily Araneoidea is a 'hooded' bothrium with a single well-developed transverse ridge, dividing its proximal and distal plates ('-type'); the advanced type is a solid dome-like bothrium without vestiges of the ridge ('-type'); there are several intermediate types reflecting various pathways and stages of the ridge reduction (united here as '-type'). The parallel trends in bothrial evolution, recognized as continuous series from the ancestral type up to the advanced one through some intermediate stages, are distinguished in each of the seven main phylogenetic lineages of the superfamily: 'tetragnathoids', 'araneoids', 'cyatholipoids', and 'theridioids' possess a complete set of the three types, while 'malkariods', 'symphytognathoids'.

A new monotypic genus of cobweb spiders from the Russian Far East (Araneae, Theridiidae).

A new theridiid spider, , is described from the Kuril Islands (Kunashir). The new genus belongs to the ' clade (clade 24)' of Agnarsson (2004). A pair of raised, fused setal sockets on the cheliceral promargin adjacent to the fang base was found to be another synapomorphy of all the 'distal theridiids' (the 'elongated central claw clade (clade 33)': argyrodins, ' clade' and theridiins).

Glebych minutissimus gen. et sp. nov., the smallest cobweb spider (Araneae: Theridiidae).

Glebych minutissimus gen. et sp. n.