The Journal of Arachnology 9:34 2

SYNEMOSYNA BICOLOR IS THE FEMALE OF SYNEMOSYNA AMERICANA (ARANEAE, SALTICIDAE )

The salticid Synemosyna is one of the better known American genera of antlike . There has been considerable confusion concerning species identification withi n the genus, because of the great differences in color and pattern between local population s of the same species, or even within the same population . Galiano (M. E. 1966 . Rev. Mus. Cien. Nat., Entomol., Buenos Aires, 1 :339-380) has discussed this problem in her revision of the genus . The Peckhams (G . W. and E. G. 1885 . Proc. Nat . Hist. Soc. Wisconsin 1885 : 23-42) first described S. americana for two males from . S. bicolor was described by them (Peckham, G. W. and E. G. 1892. Dec. Pap. Nat . Hist . Soc. Wisconsin 2: 1-83) for two females from . Both were originally described a s members of the genus Simonella, now considered a synonym of Synemosyna (Galiano 1966). Pickard-Cambridge (F . O. 1905 . Biologia Centrali-Americana, Araneidea 2 : 166-312) sent male and female specimens of Synemosyna to the Peckhams for identifica- tion. They determined these Panamanian specimens to be S . americana. Pickard- Cambridge commented that the females were certainly S. bicolor and that the males seemed to belong with the females. However, he did not believe that the males were S . americana, because of color differences and a few structural differences, none of whic h involved the palpal tarsus. He also mistakenly illustrated the palpus of S. americana as that of the male of his new species, S. decipiens (the male of which -is currently un- known). Galiano (1966) stated that a male identified in the Paris Natural History Museu m as S. bicolor was in fact, S. americana, and indicated the possibility that both species on further study might be united . I recently examined a collection of antlike salticids from northeastern col- lected by John Kochalka. Amongst them were several Synemosyna, including a male , female, and two immatures from the same locality on the same date (Colombia, Dept . Magdalena, Sierra Nevada de Santa Marta, Rio Frio, 533 meters elevation, trail, low - medium vegetation, 23 April 1975) . The genitalia of the female is that of S. bicolor, the genitalia and the chelicerae of the male are those of S . americana. Both share the same color pattern, although the male is darker with the yellow areas on the prosoma reduced . A female collected on the same site, but on 1 May 1975, has the genitalia of S. bicolor, with the same color pattern as the specimens taken in April, but with the light prosoma l areas somewhat expanded . The color pattern is different than that previously described , and is illustrated in figures 1 and 2 . The specimen illustrated is the female collected on 2 3 April.

Figs . 1-2 .-Synemosyna americana female from Colombia. Dark areas on prosoma are dark brown , pale areas are yellow . The area of the opisthosoma anterior to the constriction is dark brown with a brown scutum dorsally . This scutum is crossed a t midpoint by a narrow band of white scales . The constriction is white, and the posterior portion o f the opisthosoma is pale gray brown . 1, right lateral view ; 2, dorsal view . Total length 5 .4 mm . 2 The Journal of Arachnology 9 :34 3

On the basis of the specimens, and the contiguous range of the species involved, th e following synonymy is established, Synemosyna bicolor (Peckham and Peckham) _ Synemosyna americana (Peckham and Peckham) NEW SYNONYMY . Complete previous synonymies and diagnostic illustrations will be found in Galiano (1966) . The specimens are in the collections of John Kochalka, and I wish to thank him fo r the opportunity to examine his collection . Bruce Cutler, 1747 Eustis Street, St . Paul, Minnesota 55113 .

Manuscript received July 1980.

COLD SURVIVAL OF ARGIOPE A URANTIA SPIDERLINGS (ARANEAE, ARANEIDAE )

Salt (1961, Ann. Rev. Ent., 6:55-74) describes insects as being either "freezing toler- ant" if they can survive tissue freezing or "freezing susceptible" if they cannot survive such freezing. In the latter group, and in those species of spiders examined to date, cold survival depends entirely on an ability to lower the supercooling point (that temperature below the freezing point of the body fluids at which spontaneous freezing occurs) . For these the supercooling point represents the low lethal temperature . In specimens from a European population of Nuctena cornuta (Clerk), improved cold hardiness was demonstrated by a reduction in the supercooling point from about -8°C in summer to -23°C in winter (Kirchner and Kestler 1969, J . Insect Physiol. 15:41-53 ; Kirchner, 1973 In Effects of temperature on ectothermic organism, W . Wieser ed. , Springer-Verlag, New York) . In that study, appreciable quantities (2-3% wet weight) of the cryoprotective compound glycerol were found, but glycerol concentration was not directly related to supercooling point . Recent work by Duman (1979, J . Comp. Physiol. 131 :347-352) has shown that immature overwintering crab spiders (Philodromus sp.) and sac spiders (Clubiona sp.) accumulated a protein which influenced cold hardiness and that concentrations of this protein were reflected by the magnitude of thermal hysteresis (a difference between freezing points and melting points of the hemolymph) . Duman (1979) noted that supercooling points in these two species were lowest when therma l hysteresis was greatest. He interpretated this correlation as an indication that the protein , along with glycerol (3 .3 and 4.4% wt./vol. in the species above respectively) were respon- sible for depressed supercooling points . In the present study, egg sacs of Argiope aurantia Lucas were periodically collected from vegetation in open fields and roadsides about 15 km N of Normal, Illinois . On the following morning egg sacs were exposed for 24 hr to a selected low temperature . Some of the sacs collected 1 December 1978 were kept at ambient conditions above snow until March. Supercooling tests were not feasible on individual spiderlings so estimates wer e made of percent survival of populations within each egg sac following low temperatur e exposure. After cold exposure, egg sacs were placed at room temperature for 1-2 days,