Evolution of nuptial-gift-related male prosomal structures: taxonomic revision and cladistic analysis of the genus Oedothorax (Araneae: Linyphiidae: Erigoninae) Author Lin, Shou-Wang Author Lopardo, Lara Author Uhl, Gabriele text Zoological Journal of the Linnean Society 2022 2021-11-20 195 417 584 journal article 115951 10.1093/zoolinnean/zlab033 75b10efe-a17d-4d10-b46e-094c6a7ebf01 0024-4082 6967774 BE2B3859-8F6A-4543-8A69-91840F82377B MITRAGER VAN HELSDINGEN, 1985 Type species: Mitrager noordami van Helsdingen, 1985 . Diagnosis: Mitrager is similar to other taxa on Clade 13 in palpal and somatic features, but is characterized and can be distinguished by the following unique combination of features: 1. Paracymbium: medium- to large-sized (small in Oedothorax ); base not visible from dorsal view of male pedipalp (visible in Oedothorax ); distal setae-bearing area not prominently laterally elevated (prominently laterally elevated in some Callitrichia ); distal clasp with striae in many species (no striae in other taxa in Clade 13). 2. Copulatory bulb: embolus base protuberance absent (present in Oedothorax ); embolus retrolaterally spiral (prolaterally spiral in Oedothorax ), covered dorsally by lateral extension of radix ( LER ) in most species, except M . elongata and M. tholusa , in which it is retrolateral to the embolus (LER absent in most other species in Clade 13 except Ca. convector ); tegular papillae absent (present in many Oedothorax and Ca. macrophthalma ). 3. Palpal tibia: prolateral apophysis varies from small or absent to prominent in some species, but never elevated vertically except M. noordami (vertically elevated in many Callitrichia ); scaly prolateral spike present except M. noordami , retrolaterally directed in most species (absent in other species in Clade 13); retrolateral apophysis short, retrolaterally curved in many species (absent in Oedothorax and Callitrichia except Ca. convector ). 4. The general structure of the epigyne in Mitrager is extremely similar across species, and also similar to that of Callitrichia , Holmelgonia , Oedothorax and other related taxa. It can be distinguished from Callitrichia and Holmelgonia by the position of the entrance of copulatory ducts into the spermathecae, more mesal to the exits of the fertilization ducts. For a general description of epigynal conformation, see shared features defining Clade 13 above. Monophyly: This genus is supported by the following unambiguous character transformations: the retrolateral bending of palpal tibia prolateral spike (Ch 53, synapomorphic; lost in M. noordami ) and the wavy prolateral margin of the embolus (Ch 14, homoplastic). Description: The genus includes medium-sized erigonines mostly with a variegated opisthosoma. Male prosoma varies in degree of modification, ranging from unnoticeable ( M. unicolor and M. hirsuta ) to prominent post-PME humps, post-PME grooves, PME lobe, inter- AME-PME lobe, clypeal hump, cheliceral apophysis, pre-PME groove and modified setae. Chelicerae without mastidia. Clypeus with one sub-AME seta. For palpal and epigynal feature see diagnosis. Species included: This genus comprises 25 species (re-described below), among which 24 species are transferred from Oedothorax . Distribution: Nepal , India , Indonesia ( Java ). Natural history: Most species have been collected from broad-leaved or coniferous forest litter.