Cybaeus reducens Chamberlin & Ivie 1932
Creators: name: Bennett, Robb
name: Copley, Claudia
name: Copley, Darren
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Cybaeidae
Cybaeus
Cybaeus reducens

description: Cybaeus reducens Chamberlin & Ivie 1932
Figs 35–43, 57–58, 70
Cybaeus reducens Chamberlin & Ivie 1932: 23, fig. 57. Roewer 1954: 91. Bonnet 1956: 1303. Roth & Brown 1986: 4. Bennett 2006: 479, Figs 13–16. World Spider Catalog 2019.
Type material. Holotype ♀. U.S.A.: California: Monterey County, Pacific Grove, 17 August 1931, W. Ivie (AMNH), examined.
Other material examined. U.S.A.: California: Monterey. 6♀, 14 mi. S of Big Sur, 22.xii.1953, V. D. Roth (CAS); 3♀, 17 mi. S of Big Sur, 22.xii.1953, V. D. Roth (AMNH); 1♀, Carmel, 6.iv.1954, no collector data (AMNH); 3♀, 1 mi. N of Carmel, 21.xii.1953, V. D. Roth (CAS); 2♀, Pacific Grove, 1913, R. V. Chamberlin (AMNH); 2♀, 6.viii.1931, R. V. Chamberlin (AMNH); 6♀, 17.viii.1931, W. Ivie (AMNH); 5♀, 1.ix.1931, W. Ivie (AMNH); 2♀, Pebble Beach, Crest Road, 19.ix.1959, L.M. Smith (AMNH); Santa Clara. 1♂, 3.6 mi. from San Felipe Road on Silver Creek Road [SE of San Jose], 2.i.1983, T. S. Briggs, D.Ubick & V. F. Lee (DU).
Diagnosis. The near absence of peg setae on the patellar apophysis and the morphology of the proximal arm of the tegular apophysis diagnose the male of C. reducens. The patellar apophysis (Fig. 36) in the single known male has only two small peg setae located dorsally near the tip of the apophysis. The proximal arm of the tegular apophysis (Figs 35, 57–58) has a trifid tip and, dorsally, a prominent angular keel. No other males in the adenes group have this combination of characters.
The female is distinguished by the combination of the broad, slightly to moderately concave atrium located anteriorly on the epigynum (Figs 38, 41) and the compact, apparently strongly reduced vulva (Figs 39–40, 42–43). The females of all other adenes group species have narrow, strongly concave atria and “normal” (well-developed and not apparently reduced) vulvae (C. adenes: Figs 4–6, 9 –111; C. amicus: Figs 15–17; C. grizzlyi: Figs 28–32; C. pearcei: Figs 33–34; C. sanbruno: Figs 7–49; C. schusteri: Fig. 53; C. torosus: Figs 54–55). The atrium and vulva of female C. auburn are antero-medially located on the epigynum (Figs 21–22) and “normal” (Figs 23–24), respectively.
Description. Femora unbanded.
Male: (n=1). Proximal arm of tegular apophysis (Fig. 57) with trifid tip: anterior-most termination rounded and prominent, two others smaller and pointed. Very small inconspicuous retrolateral ridge anteriorly on tibia dorsal to carinate retrolateral tibial apophysis (Fig. 36).
CL 2.28, CW 1.65, SL 1.16, SW 1.11.
Note. This male has been paired with the females of C. reducens because of the similarity of all specimens in size, coloration, and range (although the females were all collected in a small area along the coast and the male from about 70 km away and 35 km inland).
Female: (n=31). Length of atrium (from epigastric groove to anterior margin) 0.7–1.0 times width (between lateral margins) (Figs 38, 41). Vulva (Figs 39–40, 42–43) usually very small, compact.
(n=23). CL 1.98–3.1 (2.5+0.3), CW 1.35–2.05 (1.70+0.20), SL 0.99–1.43 (1.21+0.12), SW 0.90–1.30 (1.14+0.11). Holotype CL 2.8, CW 1.98, SL 1.29, SW 1.26.
Distribution and natural history. West central California from coastal northern Monterey County inland to central Santa Clara County (Fig 70). The male was collected in early January at an elevation of 70 meters.
description: Published as part of Bennett, Robb, Copley, Claudia & Copley, Darren, 2019, Cybaeus (Araneae: Cybaeidae): the adenes species group of the Californian clade, pp. 245-274 in Zootaxa 4711 (2) on pages 259-262, DOI: 10.11646/zootaxa.4711.2.2, http://zenodo.org/record/3576931