Ninetinae Simon, 1890

Huber, Bernhard A., Eberle, Jonas & Dimitrov, Dimitar, 2018, The phylogeny of pholcid spiders: a critical evaluation of relationships suggested by molecular data (Araneae, Pholcidae), ZooKeys 789, pp. 51-101 : 53-54

Subfamily Ninetinae Simon, 1890 Figure 2

Ninetinae Simon, 1890: 95. Type genus Ninetis Simon, 1890, by monotypy. Huber 2011b: 212.

Remarks.

Ninetinae are small to tiny ground-dwelling spiders that are largely restricted to arid environments ( Huber and Brescovit 2003; BA Huber, unpublished data). With only 31 described extant species, the subfamily is by far the smallest of the five currently recognized subfamilies in Pholcidae . Ninetinae seem to be diverse in the New World (ten named genera + about four unnamed genera; BA Huber, unpublished data) where they represent the most southern (Argentina) and most northern (Canada) autochthonous pholcid records worldwide. Only two genera ( Ninetis Simon, 1890 and one unnamed; BA Huber, unpublished data) are known from the Old World.

Their short legs make them superficially strikingly different from ‘typical’ long-legged pholcids. This distinctness was recognized as early as 1893, when Eugène Simon classified the only ninetine species available to him in a separate subfamily " Ninetidinae ", as opposed to all other pholcids classified in Pholcinae ( Simon 1893). Subsequent morphological and molecular phylogenies have partly supported this view ( Huber 2000, Dimitrov et al. 2013) but never convincingly with strong support.

Our present analyses include 15 species representing eight of the eleven described genera, originating from both the New World and the Old World (Figure 2). A sister-group relationship between Ninetinae and all other pholcids is not supported by our analyses. Instead, all four analyses put Ninetinae as sister to Artema Walckenaer, 1837, and this clade is in turn sister to all other pholcids. For reasons discussed below (under Arteminae ), we consider this relationship between Artema and Ninetinae dubious. The conclusion here is that Ninetinae are ‘basal’, either with Artema or without, but in any case the external relationships of Ninetinae remain unsatisfactorily resolved and need further study.

The monophyly of the subfamily receives high to full support in all analyses but the composition is slightly different from previous concepts: the North American Chisosa Huber, 2000, originally thought to be a representative of Ninetinae ( Huber 2000), is moved to Arteminae . This move is also supported by male genitalic characters (massive palpal femur; procursus with dorsal apophysis and ventral pocket) and by somatic characters (exposed tarsal organ; reduction of epiandrous spigots; Huber 2000). Another genus that was previously ( Huber and El Hennawy 2007, Huber 2011b) thought to be a member of Ninetinae is Nita Huber & El Hennawy, 2007. As already suggested in a previous analysis ( Dimitrov et al. 2013), Nita is not a member of Ninetinae but of Arteminae .

The internal relationships of Ninetinae suggested by the molecular data are difficult to evaluate: they are mostly neither supported nor contradicted by morphological data. Two details are remarkable because they suggest that South America may not only be the most diverse region as far as Ninetinae are concerned but also the ancestral region of the subfamily. First, the analyses fully support a monophyletic North and Central American/Caribbean clade ( Pholcophora Banks, 1896; Papiamenta Huber, 2000; and unidentified taxa from Cuba and Puerto Rico; "clade 2e" in Huber 2011b) that is either nested among South American ancestors or is sister to the South American Ibotyporanga Mello-Leitão, 1944 (with reasonable support in the 4+ genes tree only). Based on its geographic distribution, we predict that the Mexican Tolteca is also a member of this clade. Second, the two Old World genera ( Ninetis and an undescribed genus from Oman) are also sister taxa (with low to modest support) and in all analyses (except for the 4+ genes analysis where Ninetis is missing) nested among South American taxa.