Taxonomic revision of Cicurina (Dictynidae)

Authors: Pierre Paquin & Nadine Dupérré

Cicurina is variable. Extremely variable. So variable that it took us about 4 years and the examination of thousands and thousands of specimens (we have an electronic document of 100 pages filled with photos of dissected females, 30 photo per page) to start to understand the incredible intra-specific variation observed in that genus. A combined approach using morphology and DNA is often necessary to understand species limits. See the example below for Cicurina arizona
The 9 specimens showed here were collected near the type locality of C. arizona (near Flagstaff AZ) a few meters from each other. It is very troubling that most epigynum are not symetrical, not particularly close to the illustrations of C. arizona given by Chamberlin & Ivie (1940), and that a morphotype could not be found twice in that series. Even more troublesome, CO1 sequences suggest that these all belong to the same species (see the gray bar in the tree).

Similar variability could be observed with most Cicurina species. It is therefore not surprising that many species have been described more than once, ie there are many synonyms out there. In a detailed examination of museum specimens, we have a new view of the species limits and we produced a detailed description of all species. For instance, see the variability that we found in the for the female C. nevadensis. As a rule, the connecting ducts of the female spermathecae are extremely variable while the spematheca itself and sermathecal pores are more stable.
The males have been mainly ignored in the taxonomy of Cicurina, most probably because they were unknown. However, they provide reliable characters, particularly the ventral view of the palp; for an unknown reason, Chamberlin & Ivie (1940) only considered the tibial apophysis. However useful, this character is not the best for species level recognition.

In addition to the numerous synonyms that we found in Cicurina, we also discovered several new species. For instance see that one that we called Cicurina satriani, most probably the sister species to C. intermedia. The female of this new species shows the usual variability of the connecting ducts. It is found in South Texas and probably in Mexico, while C. intermedia is restricted to the north west of the USA and south west Canada. We also found 2 new species from China that we intend to describe with our friend and colleague Shuqiang Li (see n.sp. #5)

We are looking forward to the day that we will propose our complete revised vision of the genus in a nice synthetic graphic way. There are still many difficulties and problems ahead, especially with the eyeless members of the genus, but we would like to wrap up this task in the next year or so. Below are a few examples of "solved cases".
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