Theridion zonulatum Thorell 1890, a senior synonym of Theridion zebrinusum Zhu 1998

Abstract

Abstract — Examination of the type material and description of Theridion zonulatum Thorell 1890 shows that this name is a senior synonym of Theridion zebrinusum Zhu 1998.Key words — Araneae, spiders, Theridion , nomenclature Introduction During a visit to Khao Sok National Park, Thailand (8° 55fa, 98°35,E), on 12 November 2013 one of us [RE] ob­served a couple of strikingly colored theridiid spiders, with a strong sexual size dimorphism. The specimens, which were found in their web on a leaf in low shrubbery along a rainforest trail, were photographed (Fig. 1), but not col­lected. Nonetheless, the unique color pattern on the female abdomen, consisting of a series of 7 narrow black stripes on a white background, allowed initial identification as Theridion zebrinusum. This was confirmed by examining the epigyne of a second female collected on 22 March the following year at the same location (Fig. 2). T. zebrinusum was first described by Zhu (1998:165) based on a single fe­male collected on 11 November 1979 in Menglun, Mangla County, Yunnan, Southern China, close to the border to Myanmar and Laos (21°55fa, 101°15,E [21°25fa, 100°36' E, according to the original publication]), but is widely dis­tributed in Southeast Asia, with records from Brunei, Singapore, peninsular Malaysia and Thailand (Koh & Ming 2014).Another specimen was photographed by one of us [GA] in riverine forest in the Mulu National Park, below 250 m a.s.l., Sarawak, Borneo, East Malaysia (4°8fa, 114°55,E; Fig. 3) on 14 February 2008.The fact that the species is widespread, apparently quite common and visually striking caused the suspicion that it might have been reported earlier from the region. A search of the classical literature describing spiders from Southeast Asia, in particular the works of Tord Tamerlan Teodor Thorell, quickly revealed a strong candidate: