Pseudodysderina, Platnick & Berniker, 2013

Platnick, Norman I. & Berniker, Lily, 2013, ffie South American Goblin Spiders of the New Genera Pseudodysderina and Tinadysderina (Araneae, Oonopidae), American Museum Novitates 2013 (3787), pp. 1-44 : 4-6

Pseudodysderina , new genus

TYPE SPECIES: Dysderina desultrix (Keyserling) .

ETYMOLOGY: The generic name refers to the similarities to Dysderina and is feminine in gender.

DIAGNOSIS: Members of this genus resemble those of Dysderina in having grooves connecting both the anterior and posterior spiracles, but lack the deep sternal excavations characteristic of that genus, and have highly modified mouthparts. In males (and, to a lesser extent, in females) the labium is greatly enlarged, with a flattened posterior portion that extends broadly posterior of the anterolateral margins of the sternum (figs. 11, 41, 61). In addition, the male endites are deeply excavated along their median and lateral margins (figs. 6, 68).

DESCRIPTION: Total length of males 1.6–2.9, of females 2.0–3.0. Carapace, sternum, mouthparts, abdominal scuta, legs orange-brown, without pattern; abdomen soft portions white, without pattern. Cephalothorax: Carapace broadly oval in dorsal view, anteriorly narrowed to 0.49 times its maximum width or less, pars cephalica strongly elevated in lateral view, anterolateral corners with strongly sclerotized, triangular extension, pars thoracica with rounded posterolateral corners, without depressions or radiating rows of pits, posterolateral edge without pits, posterior margin not bulging below posterior rim, posterolateral surface without spikes; surface of elevated portion of pars cephalica granulate (fig. 31), but granules often low (fig. 1), producing finely reticulate appearance under light microscopy, sides granulate (figs. 2, 32); fovea absent, lateral margin straight, rebordered; plumose setae near posterior margin of pars thoracica absent; marginal, nonmarginal pars cephalica, pars thoracica setae light, needlelike, scattered. Clypeus margin strongly rebordered, sinuous in front view (figs. 3, 33), vertical in lateral view, high, ALE separated from edge of carapace by their radius or more, median projection present, formed by fused small, triangular chilum; setae light, needlelike. Eyes six, well developed, ALE largest, oval, PME squared, PLE oval; posterior eye row recurved from above, procurved from front; ALE separated by more or less than their radius, ALE-PLE separated by less than ALE radius, PME touching throughout most of their length, PLE-PME separated by less than PME radius. Sternum wider than long, not fused to carapace, surface smooth (except in P. suiza , where coarsely reticulate), without pits, median concavity, hair tufts absent, radial furrows present between coxae I–II, II–III, III–IV, furrows smooth (except in P. suiza , where coarsely reticulate), radial furrow opposite coxae III absent, sickle-shaped structures absent, anterior margin with continuous transverse groove, excavated around extended base of labium (figs. 11, 41); posterior margin not extending posteriorly of coxae IV but with posterior hump (longitudinally divided in P. suiza ), anterior corner unmodified, lateral margins with

infracoxal grooves bearing anterior, posterior openings, distance between coxae approximately equal, extensions of precoxal triangles absent, lateral margins with bridges to coxae; setae sparse, light, needlelike, densest laterally, originating from surface; three transverse ridges usually connected by meandering longitudinal ridge at midline, longitudinal ridge sometimes straight, weak, or absent; lateral and posterior margins with tuberculate setal bases, in P. hermani with additional transverse row of tuberculate setal bases just posterior of anterior transverse groove (fig. 130). Chelicerae slightly divergent, anterior face with swelling, median surface of paturon deeply excavated in P. suiza and P. dracula , excavated portions bearing bifid, anteriorly directed processes in P. dracula (fig. 125); promargin with one large tooth, retromargin without teeth (figs. 4, 5, 34, 35); fangs without toothlike projections, directed medially, shape normal, without prominent basal process, tip unmodified; setae dark, needlelike, densest medially; paturon inner margin with scattered setae, distal region, posterior surface both unmodified, promargin with row of flattened setae, inner margin unmodified, laminate groove absent. Labium triangular, not fused to sternum, anterior margin indented at middle, inflated in P. suiza , same as sternum in sclerotization; with six or more setae on anterior margin, most lateral seta on each side usually enlarged, subdistal portion with unmodified setae; with dorsoventrally flat posterior extension (figs. 36, 41), more pronounced in males (figs. 6, 11). Endites same as sternum in sclerotization, distally not excavated, serrula apparently absent (figs. 7, 37); male endites each with two deep excavations, one medially along sides of labium, one laterally along base of palpal trochanter (fig. 6), those of P. suiza and P. dracula with hypertrophied tip bearing two pincerlike projections; female endites with heavily sclerotized anterior margin in P. desultrix and P. manu . Female palp without claw or spines; tibia with three trichobothria (fig. 40), patella without posterior row of ridges, tarsus elongate (figs. 38, 39). Abdomen: Ovoid, without long posterior extension, rounded posteriorly, interscutal membrane without rows of small sclerotized platelets. Booklung covers large, ovoid, without setae, anterolateral edge unmodified; both posterior and anterior spiracles connected by groove, posterior groove continued beyond spiracles toward lateral edge of postepigastric scutum. Pedicel tube medium, ribbed, scutopedicel region unmodified, scutum extending far dorsal of pedicel, plumose hairs, matted setae on anterior ventral abdomen in pedicel area, cuticular outgrowths near pedicel all absent. Dorsal scutum strongly sclerotized, in males covering full length of abdomen, no soft tissue visible from above, not fused to epigastric scutum, in females sometimes covering less than full length, width of abdomen, sometimes fused to epigastric scutum, in both sexes middle surface smooth, sides smooth, anterior half without projecting denticles. Epigastric scutum strongly sclerotized, surrounding pedicel, not protruding, small lateral sclerites absent, without lateral joints in females. Postepigastric scutum strongly sclerotized, fused to epigastric scutum in males, separate or fused in females, anterior margin unmodified, with short, posteriorly directed lateral apodemes, in males extending to at least 3/4 of abdomen length, shorter in some females. Spinneret scutum present as incomplete ring with fringe of long setae; supraanal scutum absent. Abdominal setae light, needlelike, epigastric area setae not basally thickened; dense patch of setae anterior to spinnerets absent; interscutal membrane with setae. Colulus present, tiny, with pair of setae. Anterior lateral spinnerets bisegmented, basal segment without oblique membranous strip (figs. 12, 42), posterior medians unisegmented, posterior laterals bisegmented; spigots scanned only in P. desultrix , anterior laterals with one major ampullate gland spigot and four piriform gland spigots in males (fig. 13), six in females (fig. 43), posterior medians of males with one long and three shorter spigots (fig. 14), of females with one short, medially situated spigot surrounded by at least 10 longer spigots, (fig. 44), posterior laterals of males with one long and four shorter spigots (fig. 15), of females with one short, medially situated spigot surrounded by at least 12 longer spigots (fig. 45). Legs: Femur IV not thickened, same size as femora I–III, patella plus tibia I shorter than carapace, tibia I unmodified, tibia IV specialized hairs on ventral apex, ventral scopula both absent, metatarsi I, II mesoapical comb absent, metatarsi III, IV weak ventral scopula absent. Leg spines present on anterior femora, tibiae, metatarsi. Tarsi without inferior claw. Superior claws scanned only in P. desultrix , usually with three or four large teeth situated basally on outer margins, one or two longer teeth distally on inner margins of males (figs. 17–24), three or four on inner margins of females (figs. 48–55). Trichobothrial base with one transverse ridge situated at edge of opening (fig. 25). Tarsal organs with three receptors on legs I, II, two on legs III, IV, palps (figs. 26–30, 56–60). Genitalia: Male epigastric region with sperm pore small, narrow, slitlike, situated between anterior and posterior spiracles, rebordered (fig. 16); furrow without Ω-shaped insertions, without specialized setae. Male palp of normal size, not strongly sclerotized, right and left palps mirror images, proximal segments, cymbium, bulb both yellow; embolus dark, prolateral excavation absent; trochanter of normal size, unmodified; femur dorsoventrally enlarged (fig. 9), two or more times as long as trochanter (fig. 8), without posteriorly rounded lateral dilation, attaching to patella basally; patella shorter than femur, not enlarged, without prolateral row of ridges, setae unmodified; tibia with three trichobothria (fig. 10); cymbium ovoid in dorsal view, completely fused with bulb, no seam visible, extending beyond distal tip of bulb, plumose setae, stout setae, distal patch of setae all absent; bulb shorter than cymbium, slender, elongated. Embolus situated retrolaterally to conductor, conductor varying from much smaller to larger than embolus. Female genitalia with distinct atrium (fig. 46), internally with long anterior process (lacking lateral extensions) and strong apodemes (fig. 47).

DISTRIBUTION: Widespread in northern South America.