Hesperocranum rothi, Ubick & Platnick, 1991

Ubick & Platnick, 1991, On Hesperocranum, A New Spider Genus from Western North America (Araneae, Liocranidae), American Museum Novitates 3019 (1), pp. 1-12 : 11-12

Hesperocranum rothi , new species

Figures 1-4 , 17-30

TYPES: Male holotype and female allotype from 5.8 mi. E of Highway 4 on Boards Crossing Road, Stanislaus National Forest, Tuolumne Co., California (Aug. 17,1990; D. Ubick), deposited in AMNH .

ETYMOLOGY: The specific name is a patronym in honor of Mr. Vincent D. Roth, collector of this and many other unusual spiders, who first recognized the species as new.

DIAGNOSIS: With the characters of the genus and genitalia as in figures 25-29.

MALE: Total length 2.28-3.23 (2.66 ± 0.30). Carapace length 1.13-1.36 (1.23 ± 0.07), width 0.92-1.03 (0.97 ± 0.03; N = 8); holotype total length 2.77, carapace 1.23 long, 0.97 wide, femur II 0.94 long. Eye sizes and interdistances: AME 0.08, ALE 0.09, PME 0.08, PLE 0.09; AME-AME 0.03, AME-ALE 0.02, PME-PME 0.08, PME-PLE 0.04, ALE- PLE 0.03; MOQ length 0.21, front width 0.18, back width 0.23. Palpus as illustrated (figs. 21-27).

FEMALE: Total length 2.69-4.06 (3.29 + 0.34). Carapace length 1.18-1.46 (1.32 ± 0.07), width 0.95-1.18 (1.07 ± 0.06; N = 27); allotype total length 2.73, carapace 1.27 long, 1.05 wide, femur II 1.03 long. Eye sizes and interdistances: AME 0.08, ALE 0.10, PME 0.09, PLE 0.09; AME-AME 0.03, AME- ALE 0.02, PME-PME 0.06, PME-PLE 0.05, ALE-PLE 0.03; MOQ length 0.21, front width 0.18, back width 0.23. Epigynum as illustrated (figs. 19, 28, 29).

OTHER MATERIAL EXAMINED: UNITED STATES: Oregon: Lane Co.: Limberlost Camp, 6 mi E Mckenzie Bridge , 122°02' W, 44º10' N, June 5, 1957 (B. Malkin, AMNH), 1♀ . California: Siskiyou Co.: 3 mi E McCloud , Sept. 2, 1959 (V. Roth, W. J. Gertsch, AMNH), 1♂ ; Dunsmuir , June 22, 1984 (R. West, CNC), 1♀ . Plumas Co.: 13 mi N Quincy , Sept. 5, 1988, decaying logs (D. Ubick, CDU), 1♀ . Sierra Co.: The Cups, Sierra City , Sept. 6, 1959 (W. J. Gertsch, V. Roth, AMNH), 1♀ . El Dorado Co.: 1 mi SW Meyers , May 24, 1986, May 28, 1988, May 5-6, 1990, June 16, 1990, around cabin (W. H. Tyson, CDFA, CDU), 6♀; Fallen Leaf Lake , Sept. 9, 1959 (W. J. Gertsch, AMNH), 1♀ ; 4 mi W Kyburz , Sept. 15, 1959 (W. J. Gertsch, V. Roth, AMNH), 2♂, 3♀ . Alpine Co.: Carson Iceberg Wilderness, 2.6 mi E of E shore of Lake Alpine , Aug. 17, 1990, elev. 7900 ft, under decomposing douglas fir logs (D. Ubick, CDU), 2♂ . Tuolumne Co.: 5.8 mi E Hwy 4 on Boards Crossing Road , Stanislaus National Forest , Aug. 17,1990, elev. 4000 ft, in ponderosa pine bark litter (D. Ubick, CDU, CAS), 4♂, 4♀ ; SW end of Calaveras South Grove Natural Preserve, Calaveras Big Trees State Park , Aug. 18, 1990, elev. 4600 ft, in ponderosa pine bark litter (D. Ubick, CDU), 1♀ ; Yosemite National Park, Aspen Valley , Sept. 4, 1958 (V. Roth, AMNH), 1♀ ; 6 mi S Mather , Sept. 4, 1958 (V. Roth, AMNH), 2♀ . Mariposa Co.: Yosemite National Park, Glacier Point , Sept. 27, 1944, elev. 7200-7600 ft (B. Malkin, AMNH), 1♀ . Mono Co.: Big Bend Campground, 5 mi W Lee Vining , Sept. 21, 1961 (W. Ivie, W. J. Gertsch, AMNH), 1♀ . Fresno Co.: Shaver Lake , Sept. 12, 1959 (W. J. Gertsch, V. Roth, AMNH), 2♂, 1♀ ; Kings Canyon National Park, Cedar Grove , Sept. 13, 1959 (V. Roth, W. J. Gertsch, AMNH), 1♀ . Tulare Co.: Sequoia National Forest, Sequoia Guard Station , Aug. 24, 1979, elev. 5000 ft (D. Ubick, CDU), 1♀ ; Quaking Aspen Camp , Sept. 9, 1959 (W. J. Gertsch, V. Roth, AMNH), 1♀ .

DISTRIBUTION: Oregon and California (fig. 30).

NATURAL HISTORY: Hesperocranum rothi appears to be restricted to coniferous forests, ranging in elevation from about 2500-3500 ft in Oregon and northern California and from about 4000-8000 ft in the Sierra Nevada. Known collections are from beneath logs and bark debris. The series of specimens from the Stanislaus National Forest was sifted from the bark litter accumulation surrounding the base of a single large ponderosa pine. Female specimens have been collected from May to September, males in August and September.

Three specimens, two mature males and a juvenile, were maintained in captivity for a period of five months. During this time they proved to be very reluctant feeders, refusing live Drosophila but occasionally accepting live Psocoptera and Collembola as well as freshly killed Drosophila .

Figures

Figs. 1-4. Hesperocranum rothi, new species, male. 1. Left tibia and metatarsus I, sublateral view. 2. Tibia I, ventrolateral view. 3. Tip of tarsus I, sublateral view. 4. Tarsus I, lateral view of midventral region.

Figs. 17-20. Hesperocranum rothi, new species, female. 17. Chelicerae and eye region, anterior view. 18. Eye region, dorsal view. 19. Epigynum, ventral view. 20. Posterior median spinnerets, anterior end towards top of photo. Original magnification = 700 x.

Figs. 21-24. Hesperocranum rothi, new species, male palp. 21. Prolateral view. 22. Retrolateral view. 23. Prolateral view of embolar region. 24. Ventral view.

Figs. 25-29. Hesperocranum rothi, new species. 25. Palp, prolateral view. 26. Palp, ventral view. 27. Palp, retrolateral view. 28. Epigynum, ventral view. 29. Epigynum, dorsal view.

Fig. 30. Western North America, showing records of Hesperocranum rothi.