Ogulnius gloriae (Petrunkevitch 1930)

Ogulnius gloriae (Petrunkevitch)

Epeirotypus gloriae Petrunkevitch, 1930:307, figs. 180–183 , fig. 184 [web].—Bonnet, 1956:1706.—Roewer, 1942:968. [Holotype from Ponce, Coamo Springs (nr Coamo), Puerto Rico, in PMNH, examined.]

MAP 4.—Distributions of Ogulnius gloriae (Petrunkevitch) and O. obtectus O. Pickard-Cambridge.

DIAGNOSIS.—Ogulnius gloriae uniquely possesses three closely grouped tubercles (two above, one below) on the posterior of the abdomen (Figures 120, 121).

DESCRIPTION.—Female: From Puerto Rico, HUMACAO. Total length 1.9 mm. Cephalothorax 0.89 mm long, 0.65 mm wide, 0.69 mm high; chestnut brown, mottled around periphery, elongate ridge between PME (Figures 120, 121, 123). PME slightly smaller than AME, PME separation slightly more than their diameter, AME separation their diameter. ALE, PLE PME diameter, separated by their diameter from AME, PME. Clypeus height 1.5 AME diameter. Sternum 0.38 mm long, 0.38 mm wide, reddish brown, papillate, sharply truncate and notched behind. Abdomen very large for cephalothorax size, 1.7 mm long, 1.2 mm wide, 1.6 mm high; greatly overhanging carapace, almost obscuring eyes (Figure 120). Abdominal dorsum mottled, light flecks on dark brown background; two large anterior lateral tubercles, two indistinct posterior lateral tubercles, and three grouped small tubercles on posterior midline (Figures 120, 121). Legs short, thick (1st femur diameter ∼ sternum width), annulate with dark and light bands, 4th leg longer than 1st (Figure 122).

Scale lines: 0.1 mm, except 120–122, 0.5 mm.

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

Male: From Puerto Rico, HUMACAO. Total length 1.2 mm. Cephalothorax 0.64 mm long, 0.55 mm wide, 0.55 mm high; cephalic ridge as in female. PME AME diameter, separation 1 diameter, AME separation their diameter. ALE, PLE PME diameter, separated by their diameter from AME, PME. Clypeus height 1.5 AME diameter. Sternum 0.34 mm long, 0.34 mm wide. Abdomen 0.7 mm long, 0.8 mm wide, 1.0 mm high. Color of carapace, sternum, abdomen and legs as in female. Leg lengths 1–2–4–3, proportionately longer and more slender than in female. Palp as in Figures 127–129.

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

VARIATION.—Females range in length from 1.6 to 2.4 mm, males from 0.9 to 1.2 mm. Color tan to almost black. Posterior lateral abdominal tubercles indistinct in some specimens.

NATURAL HISTORY.—The species occurs in humid shaded forest habitats or similar microclimates (for example, between shaded window bars or under roadside ferns). It seems less restricted to deep primary forest habitats than is typical of theridiosomatids. The web (Figure 105) lacks a hub, the number of radii rarely exceeds 10, and the sticky spiral spacing much exceeds the body length of the spider. The web is roughly planar and oriented vertically. Although the radii appear “anastomosed” as in those of Theridiosoma or Epilineutes, the anastomosis arises because the animals never make a well-formed hub during the construction of the non-sticky scaffolding. Thus not only does “radial anastomosis” in Ogulnius occur before, rather than after sticky spiral construction (in contrast to Theridiosoma and Epilineutes), but the anastomosis also occurs in a very different way. The two aspects of web architecture are only superficially similar in the final product, not homologous. The spider usually sits at the periphery of one of the upper radii, faces away from the web center, and slightly tenses that radius.

The eggsac is hard, leathery, pear-shaped, and suspended from nearby vegetation by a long silk line whose end nearer the sac is thickened. Spiderlings apparently escape through a hole they make on the side of the sac. A slight point opposite the suspension line (Figure 106) indicates that during construction eggsacs are doubly attached, and the lower end later cut free.

Prey items collected from webs in a window frame comprised mostly tipulids whose body length and certainly leg span much exceeded that of the spiders or the sticky spiral spacing of their webs. Forest spiders caught mainly midges and mosquitos.

RANGE.—Apparently endemic to Puerto Rico (Map 4), although similar, undescribed species occur on Cuba, Hispaniola, and Jamaica.

RECORDS.—PUERTO RICO. GUAYAMA: Cidra (immature, AMNH). HUMACAO: La Gloria, Luquillo Range ( paratype, YALE); El Yunque (, , MCZ, AMNH); Río Piedras (, AMNH); Luquillo Forest, aviary (, , MCZ); trail to summit of El Toro (, , MCZ); Rt. 191, roadside (, MCZ). MAYAGÜEZ: Bosque Estado de Maricao, 2400’ (, AMNH); Mayagüez (, AMNH); Mayagüez, University campus. PONCE: Coamo Springs Hotel, on plants near spring (, holotype, PMNH).