Cybaeus devius Chamberlin and Ivie

Bennett, Robb, Copley, Claudia & Copley, Darren, 2021, Cybaeus (Araneae: Cybaeidae) in the Nearctic: the devius and tardatus species groups of the Californian clade, Zootaxa 5026 (4), pp. 451-479 : 458

Cybaeus devius Chamberlin and Ivie

Figs 14–16 , 32

Cybaeus devius Chamberlin and Ivie 1942: 18 , fig. 48. Roewer 1954: 90. Roth and Brown 1986: 3. Bennett in Copley et al. 2009: 373, fig. 9. World Spider Catalog 2021.

Type material examined. U.S.A.: California: Holotype female. Madera County, North Fork , 37°15'N / 119°30'W, no date, no collector ( AMNH).

Diagnosis. The male of C. devius is unknown. The female of C. devius is only likely to be confused with the females of C. echo spec. nov. or C. wilsonia spec. nov. with which it shares very short spermathecal stalks and the unique copulatory duct morphology of a heavily sclerotized apical section of each copulatory duct enveloped by a very lightly sclerotized, almost diaphanous, basal section ( Figs 15–16, 18–19 , 21–22 ). In the female of C. devius ( Figs 15–16 ) the basal section of each copulatory duct is voluminous, makes three loops around the more heavily sclerotized apical section, and occupies a greater area than (and, in ventral view, partially obscures) each relatively small spermathecal base. In the female of C. wilsonia spec. nov. ( Figs 18–19 ) the basal section of each copulatory duct is also voluminous but is looped only twice around the apical section. In the female of C. echo spec. nov. ( Figs 21–22 ) the basal section of each copulatory duct loops three times around the apical section but is not voluminous (the basal and apical sections are of similar diameter) and occupies a much smaller area. Furthermore, the spermathecal bases are large and unobscured in females of C. echo spec. nov. ( Figs 21–22 ) and C. wilsonia spec. nov. ( Figs 18–19 ) bases. Finally, the basal section of each copulatory duct in C. devius travels from the atrium to the anterior margin of the vulva before beginning to loop around the apical section ( Fig. 15 ) (versus travelling only partway to the anterior margin before looping in C echo spec. nov. [ Fig. 21 ] and C. wilsonia spec. nov. [ Fig. 18 ]).

Description. Ventral tibia I macrosetae 2-1p-2-1p-0.

Female: (n=1). Atrium ( Figs 14–15 ) very small, about 1/4 width of vulva. Spermathecal heads apparently protruding dorsally from vulval ducts from within region enclosed by copulatory ducts ( Fig. 16 ).

Measurements (n=1). CL 2.11, CW 1.44, SL 1.04, SW 1.01.

Note: Cybaeus echo spec. nov. and perhaps C. wilsonia spec. nov. may be synonyms of C. devius . Insufficient specimens are available to make a strongly supported conclusion of conspecificity.

Although its coloration indicates the single specimen of C. echo is fully matured the vulva at least appears to be teneral with thin-walled ducts and weakly developed Bennett’s glands. Likewise the three known females of C. wilsonia all have apparently teneral vulvae. Clearly more specimens (especially males) from across the entire Sierra Nevada range of these three putative species need to be examined to analyze variation. At this time we consider the specimens examined here to be sufficiently distinct to warrant the recognition of three separate species.

Distribution. ( Fig. 32 ). Known only from the type locality in Madera County on the western slopes of the central Sierra Nevada.

Figures

FIGURE 32. Distributions of Cybaeus bilectus spec. nov., C. bryoncavus spec. nov., C. devius, C. echo spec. nov., and C. wilsonia spec. nov. AZ—Arizona, CA—California, ID—Idaho, OR—Oregon, NV—Nevada, UT—Utah, WA—Washington. California county names capitalized.

FIGURES 14–19. Cybaeus spp., females, copulatory organ (14–16 C. devius, holotype; 17–19 C. wilsonia spec. nov., from Wilsonia, California). 14, 17 Epigynum, ventral. 15–16, 18–19 Vulva (15, 18 ventral, 16, 19 dorsal). BG—Bennett’s gland, HS—head of spermatheca. Unlabelled solid arrows indicate basal lightly sclerotized sections of copulatory ducts which envelop apical more heavily sclerotized sections (indicated by unlabelled dashed arrows).

FIGURES 20–22. Cybaeus echo spec. nov., holotype female, copulatory organ. 20 Epigynum, ventral. 21–22 Vulva (21 ventral, 22 dorsal). Unlabelled solid arrows indicate basal lightly sclerotized sections of copulatory ducts which envelop apical more heavily sclerotized sections (indicated by unlabelled dashed arrows).