Spinestis, Saaristo & Marusik, 2009

Saaristo, Michael & Marusik, Yuri, 2009, A new species and genus of oonopid spiders (Araneae, Oonopidae) from Ukraine, ZooKeys 24 (24), pp. 63-74 : 64-65

Spinestis , gen. n.

urn:lsid:zoobank.org:act:D60FE5E2-BF2E-4C8D-8C1D-F4B0FB081B0B

Type species: Spinestis nikita Saaristo & Marusik , sp. n. from the Crimea.

Etymology: Derived from the words "spine" and " Tapinesthis " (an oonopid genus with a somewhat similar palp). Th e gender is feminine.

Composition: Only the type species.

Diagnosis: Members of this new genus can be easily distinguished from all know Palaearctic (at least Western Palaearctic) Oonopidae molles, by having 6 pairs of ventral tibial spines on legs I and II (Fig. 9). Th e male palp is similar to that of Tapinesthis inermis (which belongs to a spineless genus) due to the conical structure of the bulb (Fig. 27), but differs in having a stylus on the psembolus. Th e female genital area is also rather different from other West Palaearctic Oonopidae molles, and particularly from the sympatric Oonops pulcher (sensu Thaler 1981) , in lacking a distinct translucent receptacle. Th e endogyna with a thin, long, tube like receptaculum serves to easily differentiate Spinestis , gen. n. from all other Mediterranean Oonopidae .

Description: As for the type species.

Relationships. In terms of the habitus, this new genus resembles the generotypes of Oonops Templeton, 1835 and Oonopinus Simon, 1893 . These three genera are similar in having lock-spines on the first two pairs of legs, and a stylus on the psembolus (only one European species attributed to Oonops , O. domesticus Dalmas, 1916 , lacks a stylus. However, there are several significant differences: 1) Spinestis , gen. n. has a greater number of tibial spines (6 pairs) than any other oonopids (4–5 pairs in European Oonops sensu lato and Oonopinus ); 2) Th e stylus (St) of the psembolus is fixed (unflexible) and strongly turned (it is flexible in Oonops pulcher , and never turned in Oonopinus ); 3) All Oonops sensu lato and Oonopinus have a globular bulb, and the base of the psembolus is easily visible (Figs 28–29), whereas in the new genus the bulb is conical and the origin of the psembolus is inconspicuous. In addition, the vulva of Spinestis , gen. n. has an unusually long “receptacle” (Se), which has no widening in the terminal region.

The palpal bulb of the new species resembles that of Tapinesthis inermis (Fig. 23) and the recently described Megaoonops avrona Saaristo, 2007 . In all three species it is conical, but all other characters are entirely different. T. inermis has no leg spines, has a more or less distinct pattern on the carapace (Fig. 12), a simple psembolus lacking a stylus (Figs 13, 27), with its opening on the tapering tip as in Orchestina flagella Saaristo et van Harten, 2006 or Segestria spp. ( Segestriidae ). Th e new genus differs from M. avrona in having lockspines and by lacking spines on legs III and IV, having much shorter legs, possessing a stylus and several other characters. Females of the three genera have very different genitalia. In T. inermis the epigastric scutum is covered with dense hairs and has a large translucent pattern (Fig. 14). In M. avrona the receptacula are situated far from the epigastric furrow (Fig. 19). Aside from Oonops s.l., Oonopinus and Spinestis , gen. n., lock-spines are known in Ischnothyreus Simon, 1893 , Ischnothyrella Saaristo, 2001 and Liyonneta Benoit, 1979, These genera belong to two different genus groups of scutate oonopids ( Saaristo 2001).

At present, it is unclear which genus of Oonopidae is most closely related to Spinestis , gen. n. on the basis of morphology, but the genus is more similar to Oonops and Oonopinus (due to presence of lock-spines, a stylus and in the shape of the epigyne) than it is to Tapinesthis or Megaoonops .

Distribution. South Crimea only, western and eastern shores.