Costarina Platnick and Dupérré, 2011

Platnick, Norman I., Dupérré, Nadine, Ubick, Darrell & Fannes, Wouter, 2012, The Goblin Spider Genus Costarina (Araneae, Oonopidae), Part 1, American Museum Novitates 2012 (3730), pp. 1-64 : 3-11

Costarina Platnick and Dupérré

Costarina Platnick and Dupérré, 2011a: 50 (type species by original designation Dysderina plena O. P.- Cambridge, 1894).

DIAGNOSIS: Members of this genus resemble those of Dysderina and Simonoonops Harvey (2002) in having three transverse ridges on the sternum (figs. 163, 193), but differ in lacking grooves connecting either the anterior or posterior pairs of spiracles (fig. 44; cf. Platnick and Dupérré, 2011a: fig. 5, for Dysderina , and Platnick and Dupérré, 2011b: figs. 13, 41, for Simonoonops ).

DESCRIPTION: Total length of males 1.6–2.2, of females 1.7–2.8. Carapace, sternum, mouthparts, abdominal scuta typically orange-brown, without pattern; abdomen soft portions white, without pattern; legs pale orange, without pattern. Cephalothorax: Carapace ovoid in dorsal view, anteriorly narrowed to 0.49 times its maximum width or less, pars cephalica strongly elevated in lateral view (figs. 3, 33), anterolateral corners with slightly sclerotized triangular projections, 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 with low tubercles, producing strongly reticulate appearance under light microscopy, except on posterior U-shaped smooth area (fig. 1, except in C. blanco ), females usually with much smaller smooth areas (fig. 31, exceptions noted in species descriptions), sides granulate; fovea absent, lateral margin straight, rebordered, without denticles; 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. 2, 32), vertical in lateral view, high, ALE separated from edge of carapace by their radius or more, median projection absent (except for fused chilum); setae light, needlelike. Chilum undivided, small, triangular, fused to clypeus, seam present. Eyes six, well developed, ALE largest, oval, PME squared, PLE oval; posterior eye row recurved from above, procurved from front; ALE separated by slightly less to slightly more 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 for three transverse ridges connected by anastomosing longitudinal ridges, median concavity and hair tufts absent, with radial furrows between coxae I–II, II–III, III–IV, furrow smooth, radial furrow opposite coxae III absent, surface without pits, sickle-shaped structures absent, anterior margin with deep transverse groove (figs. 6, 43), sometime interrupted at middle (especially in species with greatly extended processes on male endites), posterior margin extending posteriorly beyond anterior edges of coxae IV as single extension, but without posterior hump, anterior corner unmodified, lateral margin 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, dark, needlelike, densest laterally, originating from surface. Chelicerae slightly divergent, anterior face with swelling (fig. 4); promargin usually with one tooth (fig. 35), retromargin usually without teeth in males, with one tooth in females; fangs without toothlike projections, directed medially, shape normal, without prominent basal process, tip unmodified (figs. 5, 36); setae light, needlelike, densest medially; paturon inner margin with pairs of enlarged setae, distal region, posterior surface unmodified, promargin with row of flattened setae (fig. 34), inner margin unmodified, laminate groove absent. Labium triangular, not fused to sternum, anterior portion set at sharp angle to flattened posterior portion, anterior margin not indented at middle, same as sternum in sclerotization; with six or more setae on anterior margin, subdistal portion with unmodified setae (figs. 7, 37). Endites same as sternum in sclerotization, those of males distally excavated between ventral, dorsal anterior processes, posterior part unmodified, serrula apparently reduced to single tooth situated near base of medially directed setae (figs. 8, 38), females with ridged lobe near tip of endite (figs. 38, 39). Female palp without claw or spines (figs. 40, 41), tibia with three trichobothria (fig. 42), patella without prolateral row of ridges, tarsus elongate. 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; anterior, posterior spiracles not connected by groove (fig. 44). 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 absent. Dorsal scutum strongly sclerotized, usually covering full length of abdomen in males, shorter in females, from above, no soft tissue visible at sides in males, some in females, not fused to epigastric scutum, middle surface, 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, in males long, semicircular, fused to epigastric scutum, in females shorter, not fused to epigastric scutum, anterior margin unmodified, with short posteriorly directed lateral apodemes. Spinneret scutum present, 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 (fig. 46). Anterior lateral spinnerets bisegmented, posterior median unisegmented, posterior laterals bisegmented; spigots scanned only in C. plena , anterior laterals with singe major ampullate gland spigot and three piriform gland spigots in males (fig. 16), four in females (fig. 47), posterior medians with four spigots in males (two with convex bases, presumably minor ampullate gland spigots, one with concave base, presumably aciniform gland spigot, fig. 16), with seven spigots in females (two with convex bases, five with concave bases, fig. 48), posterior laterals with four spigots in males (two with convex bases, two with concave bases, fig. 16), eight spigots in females (two with convex bases, six with concave bases, fig. 49). 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 absent, metatarsi I, II mesoapical comb absent, metatarsi III, IV weak ventral scopula absent. Leg spines present on anterior femora, tibiae, metatarsi, femoral spines strong, tibial and metatarsal spines long (fig. 50), absent on posterior legs (fig. 51). Tarsi without inferior claw. Superior claws (scanned only in C. plena ) with two rows of teeth, most distal tooth of internal row much longer than others, most distal tooth of outer row much shorter than others (figs. 17–24, 52–55). Trichobothrial base with numerous parallel ridges (fig. 25). Tarsal organ with three receptors on legs I, II (figs. 26, 27, 56, 57), two on legs III, IV, palp (figs. 28–30, 58–60). Genitalia: Male epigastric region with sperm pore small, oval, situated between anterior, posterior spiracles, rebordered; furrow without Ω-shaped insertions, without specialized setae. Male palp of normal size, not strongly sclerotized, right, left palps symmetrical, proximal segments pale orange, cymbium, bulb yellow, embolus dark, without prolateral excavation; trochanter of normal size, unmodified; femur of normal size, two or more times as long as trochanter, 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. 9); cymbium ovoid in dorsal view, completely fused with bulb (figs. 10–12), no seam visible, not extending beyond distal tip of bulb, plumose, stout setae absent, without distal patch of setae; bulb 1–1.5 times as long as cymbium, stout, elongated. Embolus distinctly divided into proximal and distal prongs (figs. 13–15), usually accompanied by tiny basal spur bearing sharp projections (usually visible only under scanning electron microscopy), but spur apparently absent in C. belmopan , C. coma , and C. musun . Female genitalia with conspicuous genital atrium (fig. 44); anterior genitalic process long (fig. 45); posterior apodemes usually conspicuous, directed posteriorly, but apparently directed anteriorly in C. cahui . C. izabal , and C. coma .

DISTRIBUTION: Southern Mexico south into Colombia.