American M1useum Novitates

American M1useum Novitates

AMERICAN M1USEUM NOVITATES Published by Number 1334 TiE AMERICAN MUSEUM OF NATURAL HISTORY February 21, 1947 New York City -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NORTH AMERICAN AGELENIDAE OF THE GENUS WADOTES CHAMBERLIN' BY MARTIN H. MUMA2 This review of North American spiders much smaller than the anterior laterals, an of the genus Wadotes Chamberlin is based anteriorly attached median longitudinal on material in the collections of the Ameri- tubercle or scape on the epigynum, and two can Museum of Natural History, New York, caudally projecting processes at the base of New York, the United States National the tarsus of the male palpus. Chamber- Museum, Washington, D. C., and the lin also stated that the legs of these spiders Museum of Comparative Zo6logy, Cam- are shorter than in Coras Simon which bridge, Massachusetts. Spiders in the causes the spines to be closer together. author's private collection were also studied. Wadotes is closely related to Coras, the The types of the single new species de- spiders of the two genera appearing very scribed here are deposited in the collection much alike in size, shape, and coloration on of the American Museum of Natural His- gross examination. Closer examination tory. reveals several differences which seem to be Acknowledgments are due Dr. W. J. of generic importance. Among these, in Gertsch of the American Museum, Dr. R. addition to those given by Chamberlin, are E. Blackwelder of the United States Na- the ratio of cephalic to thoracic width and tional Museum, and Miss E. B. Bryant of the space occupied by the eye area. In the Museum of Comparative Zo6logy for Coras the cephalic width is to the thoracic their cooperation in providing material for width as 3.5 to 6, while in Wadotes the ratio this study. The author would also like to is 4 to 6; in Coras the eye area occupies two- express his appreciation to Dr. Gertsch for thirds of the width of the cephalic part, helpful suggestions during the course of the while in Wadotes the eyes occupy one-half study, to Miss Bryant for comparing spec- of the width. imens with type material, and to his wife, These moderate to large spiders are quite Katharine E. Muma, for typing and cor- robust and are provided with strong, mod- recting this manuscript. erately long legs. WADOTES CHAMBERLIN The cephalothorax is subovate in outline, Wadotes CHAMBERLIN, 1925, Proc. Biol. Soc. narrowed on the cephalic part, arched Washington, vol. 38, p. 120 (Wadotes dixiensis highest in the head region in profile and Chamberlin, genotype). provided with a distinct median longitud- In 1925 R. V. Chamberlin studied the inal furrow, faint radial furrows, and dis- North American spiders previously placed tinct cephalic grooves. In color the ceph- in the genus Coelotes Walckenaer and alothorax varies from a light yellow to a separated them into two genera, Wadotes dark yellowish brown, darker on the ceph- Chamberlin and Coras Simon. The genus alic part and marked with light to dark Wadotes was erected for those species having gray, dusky bands and stripes as follows: two teeth on the lower margin of the furrow two irregular, dusky stripes arise at the median posterior median eyes and converge at the of the chelicerae, the anterior eyes median furrow, three pairs of triangular 1 Published with the approval of the Director as Paper No. 399, Journal Series, Nebraska Agricultural dusky spots form two curved submarginal Experiment Station. is seamed 2 Department of Entomology, University of stripes, and the cephalothorax Nebraska, Lincoln, Nebraska. with a fine dusky stripe. There is a sparse 2 AMERICAN MUSEUM NOVITA TES [No. 1334 clothing of dark hairs on the cephalothorax ment of the spermathecae and connecting that is most prominent on the eye area and canals. down the middle of the dorsum. Clypeal Separation of males also depends to a width is about one diameter of the anterior large extent on differences in the external lateral eyes. reproductive organs. The patella of the The robust brown to reddish brown chel- palpus bears a small, finger-like process on icerae are provided with distinct light yel- the ectal surface near the distal end. low, lateral condyles. The lower margin There is a longitudinal concavity on the of the furrow of the chelicerae is provided ectal surface of the tibia at the ventrodistal with two strong teeth, while the upper mar- corner. The tarsus is cup-shaped and gin usually carries three teeth, the middle elongate and has a longitudinal concavity one considerably larger than the other two. on the ectal side at the base. On the Sternum, labium, endites, and legs are mesal side at the base, the tarsus is drawn moderately clothed with strong black hairs out into two processes, the length and shape and are brown to yellowish brown. The of which may be used for specific separa- legs are usually slightly paler with faint tion. Two species do not have the tarsal dusky bars on the ventral surfaces of the processes as described. Wadotes tennes- femora and dusky bands on tibiae and meta- seensis Gertsch has no distinct tarsal proc- tarsi. The sternum is darker on the mar- ess, while W. calcaratus (Keyserling) has gins. Labium is longer than wide and the dorsal process nearer the ectal edge of about two-thirds the length of the curved, the tarsus. The palpal organ itself is converging endites. Sternum is subcor- rather simple, consisting of a long tubular date in outline. Legs are provided with embolus that arises near the ectobasal cor- strong black spines on the dorsal surfaces of ner of the ventral surface of the tarsus, the femora and patellae and both dorsal loops along the mesal edge to the base of and ventral surfaces of the tibiae and the crescent-shaped embolic conductor. metatarsi. The median apophysis is small and shaped The abdomen is ovate in outline, widest somewhat like one shell of a bivalve. The at or just behind the middle. It is clothed terminal apophysis is large, accompanies with a mixture of fine light and dark hairs. the embolic conductor, and apparently acts The base color is white to light yellow with as an embolic guide. In all species except light to dark gray markings as follows: the divergent forms tennesseensis Gertsch dorsum dark gray with a light, median, and calcaratus (Keyserling), the terminal basal, lanceolate stripe extending posteri- apophysis has a trifurcate, variously de- orly for one-third to one-half the length of veloped tip. In the two divergent species the abdomen, and several light chevrons the tip of the apophysis is subspatulate. or pairs of diverging light, triangular spots The form of the terminal apophysis is of on the posterior half, sides marked with specific importance. several longitudinal, interrupted, dusky On the following pages six previously ,tripes that unite just above the spinnerets. known species and one new species of Spinnerets light yellow. Posterior spin- Wadotes are described. The divergent neret longest and two-jointed with the species tennesseensis Gertsch and calcaratus basal joint longer than the apical joint. (Keyserling) are described first so that the The epigyna of these spiders are char- genotype, Wadotes dixiensis Chamberlin, acterized externally by the presence of a and the four related species may be de- fleshy, median, longitudinal scape or tu- scribed and discussed in a group. bercle that is attached at the anterior end and free at the posterior end, and a trans- Wadotes calcaratus (Keyserling) verse fleshy fold covering the openings to Figures 3, 4, 16, 17, 33, 34 the spermathecae. Specific separation of Caelotes calcaratus KEYSERLING, 1887, Ver- handl. Zool.-Bot. Gesellsch. Wien, vol. 37, p. females depends largely on the shape and 470, pl. 6, fig. 32. length of the scape, position of the sperma- Coelotes longitarsu8 EMERTON, 1889, Trans. thecal fold, and internal form and arrange- Connecticut Acad. Sci., vol. 8, p. 28, pl. 7, fig. NORTH AMERICAN WADOTES 3 2 (male, not female); BANES, 1892, Proc. Acad. corners of the epigynum behind the sperma- Nat. Sci. Philadelphia, vol. 44, p. 24, pl. 4, fig. 73. thecal fold are sclerotized for a short dis- Coelotes nigriceps BANKS, 1895, Jour. New York Ent. Soc., vol. 3, p. 82. tance in from the margins. Internally, Wadotes calcaratus CHAMBERLIN, 1925, Proc. the small obcordate spermathecae are Biol. Soc. Washington, vol. 38, p. 121. widely spaced and connected to the sperm- athecal openings by narrow connecting MALES: Total length 5.93 to 8.73 mm. canals that are twisted in three or four Carapace 2.13 to 3.00 mm. wide and 2.73 loose loops. to 4.73 mm. long. Abdomen 2.06 to 2.60 The scape of the epigynum is somewhat mm. wide and 3.26 to 4.06 mm. long. variable. In some specimens the margins Fourth leg 10.06 to 12.73 mm. long. of the scape are parallel and straight, while Spiders small to moderate in size for the in other specimens they are sinuate; in genus. Coloration typical except that some specimens the tip of the scape is dusky bands and bars on legs are some- abruptly truncate, while in others the mar- times missing, and the venter of the ab- gins taper slightly before the truncation. domen is nearly immaculate in some speci- TYPE LOCALITY: Keyserling states that mens. Structure typical. Marx found examples in Washington, Dorsal process at the base of the tarsus D. C.; Valmont, Colorado; Bridger, Wyo- of palpus making up one-fifth to one-sixth ming; and Minnesota. of the total length of the tarsus. The RECORDS: Vermont: Stowe, September 13, longitudinal concavity of the tarsus occu- 1934, one female.

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