|Pardosa altamontis |
Alpine and subalpine lake and pond edges (rocky, sandy, or earthen), moist meadows.
Females found from late May – September. Males found from early May – October. Juveniles overwinter.
Female: Total length 5-7 mm. Both cephalothorax and abdomen are primarily blackish, both dorsally and ventrally. Abdomen may have thin, light heart mark; and has several white spots. Epigynum has small hood, and has a fairly shallow cavity. The median septum is long and thin, but thickens at the posterior third to become approximately as wide at its base as the copulatory openings on either side of it. Exact ratio similar to P. sternalis, so this character cannot be used reliably where those species are interspersed.
Male: Patterned similarly to female. Tibia of palpus noticeably hirsute, all palpus segments blackish save patella. Embolus long, thin, and strongly arched. Terminal apophysis with distally pointing tip; and has large, stout basal process. Median apophysis has two processes – short one at base, long curved one at tip. Tarsus on first leg is comparable to other tarsi in proportion and color, unlike some of its close relatives.
Pardosa altamontis is a relatively uncommon species that is, in general, poorly understood. Many things can be assumed, however, based on what we know about the genus. Like all wolf spiders, it is a cursorial predator. Individuals wait patiently (often basking in sunlit areas) for prey to draw near, at which point its location is acquired with relatively acute vision (primarily the large anterior median eyes). Pursuit is generally extremely swift, and the hapless prey is dispatched with a pair of powerful chelicerae – more powerful proportionately than those of an average web-building spider, since it has no other means of restraining its prey.
Pardosa distincta and some other wolf spiders from the genus Pardosa apparently require two seasons to reach full maturity – based on the low temperatures typical of alpine and subalpine habitats, it is perhaps reasonable to assume P. altamontis may as well. Overwintering occurs in the juvenile stage. Maturity is generally reached fairly early in the active season, to maximize the chances of mating. Mating may last for an hour or so, and cannibalism is relatively rare (perhaps due to the relative similarity in size between male and female). Egg sacs are generally produced between June and August, and are carried by the female until juveniles emerge. The egg sacs themselves are constructed in two halves, is generally shaped like a partially flattened sphere, and are typically bluish or greenish in color. Typically, the juveniles are assisted in their emergence by the female, who tears a hole in the egg sac with her fangs when the juveniles are sufficiently developed. The juveniles are then carried on the female's abdomen for up to two weeks, after which they disperse.
Some Pardosa species are known to feed in surprisingly cold conditions, even preying on collembolans crawling on the surface of snow – given its choice of habitat, P. altamontis is likely capable of the same.
Unknown. Species is notoriously rare in collections.
Ambush predator of a wide variety of terrestrial arthropods.
Much of western North America. Southern Alberta and British Columbia represent the northern edge, while the southern edge extends to Utah and northern California.
|species page author||Daly, P.||2005 |