Arthur M. Chickering.
A Description of Pocobletus coroniger Simon (Araneae: Linyphiidae).
Psyche 76:54-57, 1969.

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A DESCRIPTION OF POCOBLETUS CORONIGER
SIMON (ARANEAE, LINYPHIIDAE)'*
Museum of Comparative Zoology
More than thirty years ago I began finding this species in my collections from localities in the Panama Canal Zone. For many years they were regarded as representatives of a new genus. During a period of work in the Museum National d'Histoire Naturelle in Paris in 1958 Dr. H. W. Levi made sketches of the type specimens of Pocobletus coroniqer Simon and later identified my specimens from Panama. In 1894 Simon gave a brief definition of the genus Pocobletus and in a footnote he gave a very brief description of both sexes of Pocobletus coroniger and included the species in his general treatment of the Argiopidae. No figures were given with the de- scription. Because of the uncertainties regarding the status of the species it now seems worth while to prepare a series of figures together with what I hope will be regarded as an adequate description of both sexes of this interesting species. As a basis for this description I have selected a male from Summit, Panama Canal Zone, August, 1950 and a female from Barro Colorado Island, Canal Zone, February, 1958. Other specimens from localities in the Canal Zone have also been used to supplement data derived from these two specimens. Pocobletus coroniger Simon, I 894
Figures 1-9
Pocob!eius coroniger Simon, 1894: 688, 705. The male and female syntypes are in the Museum National d'Histoire Naturelle, Paris. F. P.-Cam- bridge, 1903 : 426 ; Petrunkevitch, 1911 : 267 ; 1928 : 124; Roewer, 1942: 595; Bonnet, 1958: 3729.
Male. Total length 1.65 mm. Carapace about 0.74 mm long; about 0.61 mm wide opposite second coxae where it is widest; about 0.4 mm tall; general form essentially as shown in Figure I ; anterior projection bearing eyes; ventral margin smooth; apparently with an obscure median pit shortly below the beginning of posterior declivity. Eyes : eight in two rows ; anterior row moderately recurved ; posterior row very slightly recurved; both rows as viewed from above (some variations in relative positions of eyes and rows have been noted -
*Manuscrzpt received by the editor September 10, 1968 Pswhf 7654-57 (1960). hup Wpsycht rntclub org#6/76-054 html



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among the numerous available specimens). Ratio of eyes AME : ALE : PME : PLE = 5 : 7 : 8 : 6 (irregularities in outlines of eyes make it difficult to be accurate in measurements) ; AME separated from one another by about their radius and from ALE by slightly more than this distance; PME separated from one an- Figures 1-9. Pocobletus coroniger Simon. Fig. 1. Carapace of male; right side. Fig. 2. Eyes of male from above. Fig. 3. First right patella and tibia of male; dorso-prolateral view. Figs. 4-5. Left palp of male;
prolateral and retrolateral view, respectively. Fig. 6. Left palpal tarsus of male; ventral view. Fig. 7. Right lateral side of male abdomen. Fig. 8.
Eyes of female from above. Fig. 9. Epigynum from below.



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56 Psyche [March
other by slightly less than their radius and from PLE by their radius; ALE and PLE contiguous; long diameters always used for measurements; all eyes on a forward projection of the cephalic region of the carapace. Height of clypeus equal to nearly three times the diameter of AME. Six robust spines are placed above AME (Fig. 2). Chelicerae: moderately robust, vertical, slightly divergent; fang normal, evenly curved; fang groove, as observed in dissested speci- men, has a tooth of moderate size on each margin near base of fang and a pair of small teeth on each margin near the medial end of fang groove; on the posterior surface of each chelicera there i,s a cluster of small cusps a little above the middle; some variations in respect to teeth have been noted among the numerous specimens available for comparison and even between right and left sides in the same specimen. Maxillae: nearly three-fourths as broad as long; only slightly convergent. Lip: short, broad, only about one-third as long as maxillae. Sternum: very convex; scutiform; about as broad as long; bluntly terminated between fourth coxae which are separated by their width. Legs: 1243 in order of length; in general long and slender; with few slender spines; distinctive spines of first patella and tibia as shown in Figure 3. Palp: all segments except tarsus without special modifications; tarsus complicated (Figs. 4-6). Abdomen: general form as shown in Figure 7; without special modifications. Color in alcohol : carapace brownish with variations ; lateral sides of thoracic region with irregular, darker, radiating bands; a somewhat irregular, central V-shaped darker area. extends from the beginning of the posterior declivity toward the ocular region. Chelicerae, maxillae, lip and sternum brown with small irregular dots. Legs yellowish with darker areas. Abdomen: with a highly decorative color pattern; the anterior two thirds of the dorsal surface is yellowish with several irregular white spots; the posterior third of the dorsal surface is darker brownish surrounded by numerous irregular white inter-connected spots; ventro-laterally on each side there is an irregular white band composed of several iregular white spots; the venter is brown with a pair of small light spots somewhat behind the middle. The color pattern is difficult to describe accurately and, moreover, much variation has been noted among the numerous specimens available for comparison. Female. Total length 1.58 mm. Carapace 0.57 mm long; about 0.53 mm wide; about 0.33 mm tall; general form essentially as in male; ocular region less prominent than in male. Eyes: ratio of eyes AME : ALE : PME : PLE = 5 : 7 : 8 : 6.5; AME separated from one another by a little less than their radius and from ALE by



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about their radius; PME separated from one another and from PLE by about their radius; ALE and PLE contiguous. Height of clypeus equal to about 1.5 times the diameter of AME; the robust spines in the ocular area, so prominent in the male, are absent here (Fig. 8). Chelicerae, maxillae, lip and sternum essentially as in male as far as observed. Abdomen: as in male in all major features except the epigynum shown in Figure 9. Color in alcohol: color pattern also essentially as in male except that it tends to be some- what clearer than in that sex; the contrast between light and dark areas is greater than in the male but there is also considerable varia- tion among available specimens.
Records. In addition to the specimens selected for moderately detailed description I also have in the collection more than fifty specimens taken in the following named localities in the Panama Canal Zone: Chilibre, Barro Colorado Island, Canal Zone Forest Preserve, Frijoles, Gamboa, Madden Dam Region, Pedro Miguel, Summit Gardens, Summit. A male and two females have recently been added to the collection from Turrialba, Costa Rica, August 4, 1965
SELECTED BIBLIOGRAPHY
BONNET, PIERRE
1958. Bibliographia Araneorum. Toulouse. Vol. 2 (4). CAMBRIDGE, F. P.-
1897- Arachnids-Araneida. In: Biologia Centrali-Americana. Vol. 11. 1905. Dulau & Co., London.
PETRUNKEVITCH, ALEXANDER
1911. A synonymic index-catalogue of spiders of North, Central, South America, etc. Bull. Amer. Mus. Nat. Hist., 29: 1-809. 1928. Systema Aranearum. Trans. Conn. Acad. Arts and Sci., 29: 1-270.
ROEWER, C. FR.
1942. Katalog der Araneae. 1: 1-1040. Bremen. SIMON, E.
1892- Histoire naturelle des Araignkes. Deuxieme edition. Vol. 1. 1905. Librairie Encyclopedique de Roret, Paris.



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