Micropholcus fauroti (Simon, 1887)

Huber, Bernhard A., 2009, Four new generic and 14 new specific synonymies in Pholcidae, and transfer of Pholcoides Roewer to Filistatidae (Araneae), Zootaxa 1970, pp. 64-68 : 66

Micropholcus fauroti (Simon, 1887)

Mariguitaia divergentis González-Sponga, 2004: 64–67; pl. 1, figs. 1–9; new synonymy. Mariguitaia museorum González-Sponga, 2004: 68–70; pl. 2, figs. 1–9; new synonymy. Mariguitaia neoespartana González-Sponga, 2004: 70–72; pl. 3, figs. 1–9; new synonymy. Mariguitaia sucrensis González-Sponga, 2004: 72–75; pl. 4, figs. 1–7; new synonymy.

Justification of synonymies. Two lines of evidence strongly support the synonymies: the characters used by González- Sponga (2004) to diagnose the species, and the microhabitats of the “new” species. Biogeographic data support the conclusions.

Characters. As for Tibiosa above, most of González-Sponga’s (2004) drawings of the palps are good enough to immediately hint at M. fauroti (drawings in Millot 1941, 1946, Deeleman-Reinhold & Prinsen 1987, Saaristo 2001, Beatty et al. 2008). The retrolateral views all show the characteristic dorsal hinged process of the procursus. No comparable structure exists in any other known pholcid. More difficult to interpret are the prolateral views, especially the bulbal projections. In M. fauroti , the bulb bears several very complex projections that are partly sclerotized and partly transparent. This, together with the small size (about 0.2 mm) makes these projections difficult to understand. Nevertheless, the drawings all show the principal lines seen in M. fauroti .

Among the drawings of the male chelicerae, only the one in plate 3 comes very close to the actual situation in M. fauroti , with one pair of distal and two pairs of proximal projections. In all other drawings, the lateral proximal pair is missing. These proximal apophyses are difficult to see unless the chelicerae are detached from the specimen. The drawing in plate 1 suggests that González-Sponga did not detach the chelicerae: it shows the chelicerae together with the palpal endites, erroneously fused into a single structure.

The epigynum of M. fauroti is an externally simple oval plate with a transparent knob on its posterior border. The most distinctive feature is a median crescent-shaped internal structure visible through the cuticle. This is shown in all epigynal drawings in González-Sponga (2004). Lateral structures of similar shape but variable size (as in plates 2 and 3) are more or less visible in most M. fauroti females.

All species diagnoses in González-Sponga (2004) include measurements, but in which sense these are supposed to be diagnostic is not stated. All measures are clearly within the range of M. fauroti (e.g. tibia 1 length: 22 males from around the world: 5.0–7.0 mm, 39 females: 4.4–5.6; unpublished data). The four males and three females measured by González-Sponga (2004) are in fact surprisingly similar (e.g. tibia 1 length, males: 5.7–6.2 mm, females: 4.8–5.1). As for carapace shape and eye positions, see Tibiosa above.

Finally, one surprising character emphasized by González-Sponga (2004) is the single trichobothrium on the male palpal tibia in all “new species”. All M. fauroti specimens (in fact all pholcids) I have ever seen have two trichobothria on the palpal tibiae. Since both trichobothria are equally easy (or difficult) to see, I have no explanation for this. A single trichobothrium was described by the same author for Anomalaia (now Metagonia ) mariguitarensis (González-Sponga 1998); subsequent study has shown that it also has two trichobothria ( Huber 2000).

Microhabitat. In the introduction, González-Sponga (2004) writes that Mariguitaia occurs “both in forests and in human dwellings” (my translation). However, three species were found in buildings only, the fourth under shrubs in the village of Mariguitar. No specimen was collected in a forest.

Biogeography. The original distribution of Micropholcus is difficult to reconstruct. Only one congener of the type species is known: Micropholcus jacominae Deeleman & van Harten, 2001 from Yemen. Micropholcus fauroti is widely distributed around the world (Deeleman & Prinsen 1987, Saaristo 2001). I have seen M. fauroti from many countries, including Venezuela (Península de Paraguaná: Coro), Cuba, the Dominican Republic, and the USA (unpublished). A further record for Venezuela (Zulia: Maracaibo) was recently published by Colmenares-García (2008). The fewer records for this species than for C. lyoni and P. globosus may partly be due to the small size and pale colour of this species.