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
CORNITIBIA
GEN. NOV.
Type
species:
Oedothorax simplicithorax
Tanasevitch, 1998
Derivatio nominis:
The genus name refers to the tusklike male palpal tibia apophysis of the
type
species. Genus gender feminine.
Diagnosis:
Males:
This genus is distinguished from all other erigonines by the distinct male palpal tibia, bearing one tusk-like, seta-free apophysis rising from the proximal half of tibia and pointing apically, and several long thorns from enlarged setal bases both retrolateral and prolateral to the apophysis, as well as by the unique morphology of the embolic division (as shown in
Fig. 69D
). The lack of a membranous connection between the radix and the embolus and the presence of radical lateral tooth clearly distinguish this species from all taxa on Clade 13.
Females:
Unknown.
Species included:
Cornitibia simplicithorax
(Tanasevitch, 1998)
comb. nov.
Phylogenetic justification:
In the original description of
Oedothorax simplicithorax
(Tanasevitch 1998)
, no account was given regarding the diagnostic characters used for assigning this species to
Oedothorax
, and the embolic division of this species was not clearly illustrated. Later (
Tanasevitch, 2015
), diagnostic characteristics of
Oedothorax
were described, including features related to the embolic division, which match most species on Clade 13. Examination of
Co. simplicithorax
revealed a greatly different embolic division configuration in this species, with an pale, ventro-prolaterally situated ‘anterior radical process’, different from that of other species examined in the present study. In the phylogeny (
Fig. 2
), this species is sister to a clade comprising the majority of our taxon sample (Clade 10), and not closely related to
Oedothorax
,
Callitrichia
,
Mitrager
or other taxa in Clade 13. After a comprehensive literature research of erigonine male palpal structures, no morphologically resembling species was found that can suggest at least a preliminary (i.e. phenetic) close relatedness. Base on these findings and its relatively basal phylogenetic placement, this species neither belongs to
Oedothorax
, nor can it be transferred to any other established taxon. We, therefore, propose the erection of
Cornitibia
gen. nov.
for this species.