E. B. Bryant.
Redescription of Cheiracanthium mildei L. Koch, a Recent Spider Immigrant from Europe.
Psyche 58:120-122, 1951.

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REDESCRIPTION OF CHEIRACANTHIUM MILDEI
L. KOCH, A RECENT SPIDER IMMIGRANT
FROM EUROPE
BY ELIZABETH B. BRYANT
Museum of Comparative Zoology
The fauna of New England has often been compared to that of Great Britain, which has about the same area. Dr. B. J. Kaston in his recent book, "The Spiders of Connecti- cut",
1948, states that 644 species of spiders have been recognized in New England, and that 72 of these are common to Europe. Some are endemic, but others have been introduced by commerce. In the summer of 1949, a spider carrying a cocoon of eggs and new to our fauna, was brought to the museum by Dr. A. M. Chickering. It proved to be Cheiracanthium mildei L. Koch, a species native to southern Europe.
The genus is known in Europe by 34 species and pre- viously in North America by only one, Cheiracanthium in- clusum (Hentz), found from New England south to Florida and the islands of the Caribbean. Cheiracanthium mildei was first described from Meran, Dalmatia, in 1864. It has
subsequently been reported from Switzerland, Hungary, the Caucasus and Palestine. Since 1.949, when the female mentioned above was recognized, additional specimens of both sexes have been found in Connecticut and New York, indicating that the species is established in our area. I wish to express here my thanks to Dr. W. J. Gertsch, of the American Museum of Natural History, to whom we are indebted for the gift of a pair of this species taken at New Rochelle, New York, June, 1947.
Cheiracanthium mildei L. Koch
Figures 1-3
Cheiracanthium mildei L. Koch, 1864, p. 144. 8 s in sudlichen Tirol (Meran) in Dalmatien, (Sammlung des Herm Grafen Keyserling)".
120




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19511 Bryant - Cheira,canthium mild ei 121 Female: Length, 7.0 mm., ceph. 3.0 mm. long, 2.5 mm. wide, abd. 4.6 mm. long, 3.1 mm. wide.
Cephalothorax pale yellow, anterior margin truncate, about half the greatest width, moderately high, no thoracic groove but the area slightly darker and called by Simon a "false groove"; eyes subequal, anterior row slightly re- curved, eyes equidistant, posterior row a little longer than the anterior, procurved, eyes equidistant, lateral eyes Pigs. 1-3, Cheiracanthium mildei. Fig. 1. Left palpus, retrolateral view. Fig. 2. Fourth metatarsus, ventral view. Fig. 3. Epigynum, ventral view.
separated by a radius; quadrangle of median eyes narrower in front and as high as wide behind; clypeus below a.rn.e. about equal to a radius of a.m.e.; mandibles vertical, large, fang groove oblique, lower margin with three contiguous teeth; labium wider than long; maxillae twice as long as the labium with the tips widened; sternum pale, smooth, convex, longer than wide, (5.0 :4.1) ; abdomen pale, oval,



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122 Psyche [September
convex, with no markings; legs, 1-2-4-3, pale, spines weak and inconspicuous, 1 pair, tibia, ventral, 2, median, meta- tarsus longer than the tibia, spines, ventral, 2 at the base, I1 pair, tibia, ventral, 2 at the base, metatarsus, 2 at the base; epigynum, area wider than long, divided about the middle by a transverse dark chitinized curved ridge, the anterior half with a pair of widely separated oval depres- sions, the posterior half divided by parallel vertical dark lines into a broad median septum with the extreme lateral margins ending in small circular sacs below the surface, as figured.
According to the late Dr. de Lessert of Geneva, Switzer- land, the epigynum is often filled with a resin that obscures the various parts, but the transverse ridge is distinct. Male: Length, 7.0 mm., ceph. 3.1 mm. long, 2.5 mm. wide, abd. 4.5 mm. long, 2.2 mm. wide.
Cephalothorax pale, with short hairs, quite flat, anterior margin less than half the greatest width, thoracic groove faintly indicated ; eyes as in the female ; clypeus less than a radius of a.m.e.; mandibles ventral, long and narrow, teeth on the fang groove as in the female; labium as in the female; maxillae emarginate on the outer side; sternum as in the female; abdomen pale, oval; legs, 1-2-4-3, pale, spines black and conspicuous, 1 pair, femur, dorsal, median, 2, prolateral, 1, tibia, ventral, 2-2-2-2, metatarsus, 2, basal, I1 pair, femur, dorsal, 2-2, prolateral, 1, heavier than on I femur, tibia, 2-2-2-2, metatarsus, 2, basal, IV metatarsus, ventral, 14 short spines, (fig. 2) much shorter and heavier than the lateral spines; palpus (fig. 1) about as long as the cephalothorax, pale, with the terminal joint much darker, patella as long as wide, tibia about three times as long as wide, but not as long as the cymbium, with two short dark dorsal cusps at the tip, the dorsal cusp short and straight, the 'etrolateral cusp longer, more slender with the tip incurved, the tip of the slender process from the cymbium resting between the two, palpal organ confined to the lower two-thirds of the cymbium, bulb protruding from the cavity, embolus starts on the side about the middle, passes below the bulb as a slender tube and ends on the margin about opposite to the origin.




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1.9511 Bryant - Cheiracanthium mildei 123 The eggs are flesh-color, about 0.5 mm. in diameter, in a compact mass, loosely enclosed in a thin transparent cocoon.
9 Massachusetts ; Cambridge, 26 July, 1949, (Chickering) 8 Massachusetts ; Cambridge, in museum, 18 July, 1947, (Bryant)
8 Massachusetts ; Brookline, 27 July, 1947, (Bryant) 6 9 New York; New Rochelle, June, 1947, (Lacy) The male of Cheiracanthium mildei is easily separated from that of C. inclusum by several characters. The tibia of the palpus of mildei has two short processes at the tip, while inclusum has one long process which interlocks with a similar process from the cymbium; mildei has on the fourth metatarsus a ventral row of short black spines that are very conspicuous; and on the second femur the pro- lateral spine from a raised base is much smaller than on inclusum. The females can be separated by the epigyna. In nzildei the area is divided by a dark transverse bar, while in inclusum, the epigynum is an oval transverse pit which shows no structure.
REFERENCES
KOCH, L.
1864. Die europaischen Arten der Arachnidenga.ttung Cheiracanthium. Abd. naturh. Ges. Nurnberg, 1864, pp. 132-162. LESSERT, R. DE
Catalogue des Invertebres de la Suisse. Fasc. 3, Araignees. Musee d'histoire naturelle de Geneve 1910, pp. 1-635, 250 figs. SIMON, E.
1914-1937. Les Arachnides de France, 6, pp. 1-1298, figs. 1-2028. (pp. 309-1298 publiee L. Berland et L. Page.) NEW SYNONYMY IN THE ARMY ANT GENUS AENICTUS Sc~uc~~R~.-Aenictzis deuqueti Crawley (1923, Ent. Rec., 35:177, worker) is a new synonym of Aenictus turner! For- el (1900, Ann. Soc. Ent. Belg., 4.4 :75, worker). I compared
types of Forel's and Crawley's species in the British Muse- um. Crawley's distinctions are inconsequential or else, as in the case of the color, inaccurately described. - W. L. BROWN, JR., Museum of Comparative Zoology.



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