Epeirotypus chavarria Coddington 1986

Epeirotypus chavarria

TYPE.— holotype and one , three paratypes from Costa Rica, Heredia Province, near Puerto Viejo, Organization for Tropical Studies Finca La Selva, 50 m, J. Coddington, coll., 25.iii. 1979, in MCZ.

ETYMOLOGY.—The name is a noun in apposition, honoring Sr. Rafael Chavarría, the late administrator of Finca La Selva, of Puerto Viejo de Sarapiqui. The ending of “chavarria” conflicts with Recommendation 31a of the ICZN, but in this case an exception seems warranted to ease pronunciation of the name.

DIAGNOSIS.—Males and females of chavarria may be distinguished from all other species of Epeirotypus by the color pattern: an off-white abdomen with numerous very white guanine speckles. The genitalia are very similar to those of other Epeirotypus species.

DESCRIPTION.—Female: Paratype. Total length 2.4 mm. Carapace whitish yellow, cephalothorax 0.98 mm long, 0.83 mm wide, 0.86 mm high; white, head region slightly elevated, lateral portions strongly developed into “shoulders” (Figure 57). Sternum 0.52 mm long, 0.45 mm wide, whitish yellow. Abdomen 1.3 mm long, 1.4 mm wide, 1.7 mm high; smoothly ovoid, uniformly white with numerous white small guanine dots on dorsum and sides, absent on venter (Figures 56, 57). AME slightly smaller than PME, separated by their diameter. PME separated by slightly less than their diameter. ALE, PLE subequal to AME, separated from AME, PME by their diameter. Clypeus AME diameter. Epigynum with central pit; posterior margin with transverse groove, groove bisected medially by ridge; posterior rim closely appressed to surface of abdomen (Figures 58, 59). Copulatory ducts ridged, simple (Figures 59, 60).

Leg lengths of female described above (±0.02 mm).

Male: From type-locality. Total length 1.9 mm. Cephalothorax 0.86 mm long, 0.76 mm wide, 0.83 mm high; head region elevated, lateral portions strongly developed into “shoulders” (Figure 61). Sternum 0.47 mm long, 0.41 mm wide. Abdomen 1.1 mm long, 1.1 mm wide, 1.3 mm high. AME slightly larger than PME, separated by their diameter. PME separated by their diameter. ALE, PLE subequal, slightly smaller than AME, separated from AME, PME by their diameter. Clypeus 3 times AME diameter. Color of carapace, sternum, legs, and abdomen as in female. Palp as in Figures 62–65.

Leg lengths of male described above (±0.02 mm).

VARIATION.—Females range in length from 2.0 to 2.8 mm, males from 1.4 to 2.0 mm. Coloration may be slightly yellowish in life, but never very dark.

NATURAL HISTORY.—The species occurs only in primary, wet lowland rain forest, making its webs within 2 m of the ground, on shrubs or other woody substrates. The web is shown in Figures 44, 45. Females suspend eggsacs between the tension line and other silk lines or the substrate. One female observed for about 2 months constructed a total of 6 eggsacs. Eggsacs in collections contain from 6 to 12 eggs. The species seems to prefer tree buttresses, palm roots, and wind falls as web sites, with the tension line facing inward towards the substrate. Males are found at the periphery of the female web.

RANGE.—Thus far, the species is known only from the type-locality.

RECORDS.—COSTA RICA. HEREDIA: nr Puerto Viejo de Sarapiqui, OTS Finca La Selva (, , numerous records, MCZ). The locality is the same as the southernmost dot on Map 2, E. brevipes.

Naatlo, new genus

TYPE-SPECIES.—Naatlo sutila, new species.

ETYMOLOGY.—Na'atlo is the name given by Navaho Indians to “cat's cradle” string figures, an art taught to them by a deity known as Spiderwoman. The name is taken to be feminine.

DIAGNOSIS.—Naatlo is diagnosed by the presence of the epigynal flap hinged anteriorly and covering the copulatory bursa in the females (Figures 78, 88, 93) and the reduced conductor and the more complex embolic tip in the males (Figures 71, 73, 83, 97). Somatic morphology most resembles that of Epeirotypus, but Naatlo is readily distinguished by these diagnostic features.

DESCRIPTION.—Total lengths 1.7 to 3.0 mm. Cephalothorax glabrous, light tan, sternum slightly darker. Head region (narrower and less distinct in males) only somewhat higher than thoracic region and set off by deep depression or groove (Figure 74). Lateral region of carapace opposite fovea high, forming “shoulders” (Figure 86). AME PME diameter, separation their diameter and similarly from ALE. PME ovoid, separation their diameter and similarly from PLE. ALE, PLE juxtaposed, subequal to PME. Male eye group more compact, AME projecting slightly beyond clypeus (Figure 81). Chelicerae robust, 2 to 3 prolateral and retrolateral, discrete teeth. Sternum longer than wide, rounded behind. Legs light tan proximally, darker reddish tan distally. Legs I, II much more robust than III, IV; female femur I width about carapace diameter. Tarsi with numerous serrated bristles ventrally. Male legs I, II less robust, proportionately longer and thinner than in female. Abdomen ovoid, without prominent humps. Species distinguishable by abdominal shape and color patterns or, in doubtful specimens, by genitalic details.

NATURAL HISTORY.—Preferred habitat is typical of the family, wet or humid shaded forest, from near sea level to montane forest (e.g., 2300 m in Colombia). The webs are similar to those of Epeirotypus, with 14–20 radii and a similar number of SS loops. All radii reach the hub (Figure 69). At least two hub loops and a tension line are present. Judging from the robust first and second legs, these spiders also exert considerable force to tense their webs into a cone (cf. remarks under Epeirotypus). Eggsac form apparently is diverse. One eggsac accompanying a specimen of splendida from Colombia was a ball of fluffy silk attached directly to a leaf. An undescribed species from Queensland, Australia, however, had a papery sack suspended from two points (cf. remarks under Ogulnius, Epeirotypus).

SPECIES.—Theridiosoma fauna Simon, 1897b, T. sylvicola Hingston, 1932, and T. splendidum (Taczanowski, 1873) are here transferred to Naatlo. The identity of sylvicola is somewhat uncertain, because no Hingston specimens are extant. He did provide a detailed description, in particular mentioning a “subtriangular” epigynum (1932:376). Specimens from Guyana in the MCZ and AMNH agree with Hingston's description, and thus may be referred to sylvicola. Archer (1953:12, fig. 25) also provided a brief description and figure of the epigynum, as well as identifying several specimens as T. sylvicola (currently in the AMNH). Both authors overlooked that the subtriangular structure on the epigynum is merely the ridge on the epigynal flap, not the epigynum itself. A neotype for sylvicola should be designated when Naatlo is revised. Undescribed species are known from South America, Australia, and New Guinea.

RANGE.—The genus occurs at least in Central and South America, Australia, and New Guinea.