Sicarius, Walckenaer, 1847

Magalhaes, Ivan L F, Brescovit, Antonio D & Santos, Adalberto J, 2017, Phylogeny of Sicariidae spiders (Araneae: Haplogynae), with a monograph on Neotropical Sicarius, Zoological Journal of the Linnean Society 179 (4), pp. 767-864 : 795-798

THE SICARIUS / THOMISOIDES CONTROVERSY AND

THE NAME OF THE TYPE SPECIES

Nicolet (1849) proposed the genus Thomisoides to contain seven new Chilean species. While Nicolet’s study was still in print, Walckenaer somehow had access to the unpublished plates that depicted four of Nicolet’s species. He took advantage of this and, in his ‘Histoire Naturelle des Insectes: Apteres’ (Walckenaer, 1847), he stated that (1) the four species depicted in Nicolet’s plate were the same and (2) the name Thomisoides was unsuitable for the genus, as these spiders did not seem to be related to those in the genus Thomisus Walckenaer. Thus , he proposed Sicarius as the name of the genus and included a single species in it, S. thomisoides , considering four of Nicolet’s species as synonyms of it. Paradoxically, he decided to maintain the same name he rejected for the genus as the specific epithet. As Walckenaer’s work (1847) was published 2 years before Nicolet’s (1849), Sicarius has priority over Thomisoides . This fact did not prevent the use of Thomisoides in subsequent spider species descriptions ( Butler, 1877; Keyserling, 1880; Holmberg, 1881; Mello-Leit ao ~, 1936), in some cases with explicit (but unjustified) rejection of the use of Sicarius ( Holmberg, 1881; Chamberlin, 1916; Mello-Leit ao ~, 1933). This had already been discussed by Pickard-Cambridge (1899a: 17), who stated that ‘if we regard Sicarius as the proper generic title [...] we must also regard thomisoides as the proper specific title [...]’. Thus, he designated S. thomisoides as the type species of Sicarius (against Simon , 1893, who had considered Nicolet’s S. terrosus as the type species), a decision with which we agree. However, the arguments of Pickard-Cambridge (1899a) were largely ignored, and the name S. thomisoides came into disuse until Magalh ~ aes et al. (2013) accounted for it. Bonnet (1958) discussed that Sicarius should be regarded as the proper generic name, but he argued that the name of the species was of lesser importance and thus he suggested retaining the name terrosus . Following him and Simon (1893), catalogues had been listing S. terrosus as the type of Sicarius (e.g. Roewer, 1942; Brignoli, 1983; World Spider Catalog, 2015).

One could argue that S. thomisoides could be considered as a nomen oblitum to preserve the stability of S. terrosus . However, the concept of this species has never been clear, and the name S. terrosus has been used to refer to a variety of species – for instance, to S. boliviensis sp. nov. (by Chamberlin, 1916) and to S. levii sp. nov. (by Mello-Leit ao ~, 1941; Gerschman de Pikelin & Schiapelli, 1979; Binford et al., 2008, 2009). To our knowledge, the name S. terrosus was very seldom used in the literature to refer to the correct Chilean species, and thus we see no reason to keep it over the older S. thomisoides .

Species included. Sicarius thomisoides Walckenaer, 1847 , Sicarius fumosus ( Nicolet, 1849) , Sicarius crustosus ( Nicolet, 1849) , Sicarius lanuginosus ( Nicolet, 1849) , Sicarius yurensis Strand, 1908 stat. nov., Sicarius peruensis ( Keyserling, 1880) , Sicarius gracilis ( Keyserling, 1880) , Sicarius andinus sp. nov., Sicarius boliviensis sp. nov., Sicarius rupestris ( Holmberg, 1881) , Sicarius mapuche sp. nov., Sicarius levii sp. nov., Sicarius tropicus (Mello-Leit ~ ao, 1936), Sicarius cariri Magalh aes ~, Brescovit & Santos, 2013, Sicarius ornatus Magalh ~ aes, Brescovit & Santos, 2013, Sicarius diadorim Magalh aes ~, Brescovit & Santos, 2013, Sicarius saci sp. nov., Sicarius jequitinhonha sp. nov., Sicarius rugosus (F.O. Pickard-Cambridge, 1899) and Sicarius utriformis ( Butler, 1877) .

CHILEAN SPECIES, NICOLET’ S SEVEN NAMES, AND THE ABSENCE OF SICARIUS IN VALDIVIA

Chile was arguably the country holding most species in need of revision. Nicolet (1849) described seven species from there based on poor diagnostic characters, and Keyserling (1880) added one more species. Despite being one of the most common arthropods in the desertic coast of Chile, specific identification was impossible until now. After our revision, we conclude that some species were named several times, and reduce the number of species to five ( S. thomisoides , S. fumosus , S. crustosus , S. lanuginosus and S. yurensis stat. nov., the last being newly recorded for the country).

Nicolet described seven species of Thomisoides in his seminal work on Chilean spiders (1849) based on specimens collected by Claudio Gay. He sorted them into two groups, the piriformes (including S. terrosus , S. rubripes and S. minoratus ) and the rugosas (including S. fumosus , S. crustosus , S. deformis and S. lanuginosus ). All types that could be found in the MNHN in Paris (see Ram � ırez, 1989) are immatures, except for those of S. rubripes and S. nicoleti . Tragically, these types (along with that of Thomisoides nicoleti Keyserling ) were under study in the Instituto Butantan in 2010, when part of its collection was lost in a fire, and have not been located after the incident. In our view, Nicolet’s piriformes correspond to a single species, S. thomisoides . On the other hand, we here recognize three Chilean species which fit in his rugosas group (in which he included four nominal species). Basing on Nicolet’s work, it is difficult to match his names with the three species we recognize, as the types are immature and the localities are unspecific (see next paragraph). However, we avoided considering his species as doubtful, and preferred to use somatic morphology to match names to the species we recognize.

Nicolet (1849) gave specific localities for only a few species (Valdivia for S. terrosus and S. deformis ; Chile for S. rubripes ), but labels on the specimens indicate they all come from Valdivia (see Ram � ırez, 1989). However, Sicarius seem to be completely absent from this region: the closest record of Sicarius comes from 400 km to the north, and we and several colleagues collected near Valdivia and have not yet found a Sicarius . On the other hand, Sicarius are very common in central and northern Chile – in some places, almost every rock has an individual lying beneath it. It is known that Gay collected throughout most of Chile, including all the places where Sicarius are most common ( Pizarro, 1944). Having this in mind, to us it seems very unlikely that Gay collected seven different species of Sicarius in Valdivia , but nowhere else. Thus, it seems that Nicolet’s specimens were mislabeled at some point, and that his localities are unreliable – we cannot say where they came from, except for the country ( Chile).