Cybaeina minuta (Banks), 1932

Bennett, Robb, Copley, Claudia & Copley, Darren, 2023, Revision of the western Nearctic spider genus Cybaeina including the description of Neocybaeina gen. nov. and Rothaeina gen. nov. (Araneae: Cybaeidae: Cybaeinae), Zootaxa 5318 (1), pp. 97-129 : 103-105

Cybaeina minuta (Banks)

Figs 1 , 6–7 , 12–13 , 16–17 , 22–24 , 28

Cybaeus minutus Banks 1906: 95 .

Cybaeina minuta Chamberlin and Ivie 1932: 28 , figs 5–14, 28–30. Exline 1938: 8. Roewer 1954: 86. Bonnet 1956: 1296. Roth and Brown 1986: 2. Bennett 2005: 88, figs 22.20, 22.25, 22.28–22.29, 22.31, 22.34. Bennett 2017: 99, figs 23.20, 23.25, 23.28–23.29, 23.31, 23.34. World Spider Catalog 2023.

Type material examined. U.S.A.: Washington: Holotype female. Thurston County, Olympia, no date, no collector ( MCZ).

Other material examined. CAN: British Columbia: 1♀, Brooks Peninsula , shoreline moss, 50.203°N 127.631°W, 28.ix.2006, C. Copley & D. Copley ( RBCM) ; 2♀, Kyuquot , 1–10.ix.1930, S.L. Neave ( AMNH) ; 1♀, Kyuquot , 1.vi.1952, S.L. Neave ( CNC) ; 1♁ 2♀, Kyuquot, Clanninick Grass Flats , 3.vii.1956, S.L. Neave ( AMNH) ; 1♀, Kyuquot, Meyer’s Cove , 11.iv.1959, S.L. Neave ( AMNH) ; 1♀, Kyuquot , Neave’s Is., 29.x.1958, S.L. Neave ( RBCM) ; 1♁, Kyuquot , Union Is., 25.ix.1959, S.L. Neave ( AMNH) ; 1♀, Kyuquot, Walter’s Cove , 24.iv.1959, S.L. Neave ( AMNH) ; 1♀, Tofino , 28.vii.1966, E. Thorne ( CNC) ; 1♀, Victoria , 10.viii.1930, S.L. Neave ( CNC) . U.S.A.: Oregon: Tillamook, 1♁, Bay City , 6.viii.1929, R.V. Chamberlin ( AMNH) . Washington: Thurston, 1♁, Olympia , 1.xii.1933, H. Exline ( CAS) ; 1♀, Olympia , 22.viii.1955, V.D. Roth ( CAS) .

Other material not examined. U.S.A.: Washington: Thurston, 1♁, Evergreen State College , 160′, 47.074°N 122.98°W, ix–x.1992, Evergreen Biodiversity Class ( UWBM) ; Wahkiakum, 1♀, Grays River Valley , 150′, 46.361°N 123.574°W, 27–28.x.1984, R. Crawford ( UWBM) ; 1♀, Hendrickson Canyon , 50–150’, 46.367°N 123.666°W, 26.x.1984, R. Crawford ( UWBM) .

Diagnosis. The differentiation of specimens of C. minuta from those of C. confusa and C. dixoni spec. nov. is discussed in the diagnoses of the latter two species.

Description. As in diagnosis and description of the genus and the diagnoses of C. confusa and C. dixoni spec. nov. Additional descriptive characters presented here.

Male (n=4): Tegular apophysis ( Figs 6–7 ) with narrow base; distal arm with narrow prolaterad tip, distoretrolateral edge folded over ventrally; proximal arm with simple, elongate, sinuous, proximo-prolaterad tip.

Measurements (n=4). CL 2.08–2.23 (2.16), CW 1.68–1.75 (1.70), SL 1.13–1.17 (1.15), SW 1.03–1.08 (1.06).

Female (n=13): Atrium ( Fig. 22 ) on posterior edge of epigyne. Vulva ( Figs 23–24 ) with copulatory ducts contiguous only at atrium; spermathecal heads undifferentiated from spermathecal stalks except for presence of primary pores; primary pores dorsal, inconspicuous; spermathecal stalks elongate, convoluted, well sclerotized; spermathecal bases rounded, relatively small (about 1/3 length of vulva); fertilization ducts slender.

Measurements (n=12). CL 1.78–2.13 (1.99+0.11), CW 1.30–1.58 (1.46+0.09), SL 0.98–1.12 (1.07+0.05), SW 0.94–1.04 (1.00+0.04). Holotype CL 2.1, CW 1.55, SL 1.08, SW 1.04.

Distribution and natural history. ( Fig. 28 ). Cybaeina minuta is relatively widespread but rarely encountered in the coastal western Nearctic area where it has been recorded from the northwest coast of Vancouver Island, British Columbia, Canada, south to coastal northwestern Oregon, U.S.A. Males have been collected from early July to early December. The most recent known record for C. minuta is from 2006. This species is ranked nationally vulnerable in Canada ( Canadian Endangered Species Conservation Council 2022); a conservation rank for this species in the U.S.A. has not been determined.

Figures

FIGURE 28. Distributions of Cybaeina species. Cybaeina confusa, C dixoni spec. nov., and C. minuta. AB—Alberta, AZ— Arizona, BC—British Columbia, CA—California, ID—Idaho, MO—Montana, OR—Oregon, NV—Nevada, UT—Utah, WA— Washington.

FIGURES 1–2. Cybaeina and Rothaeina gen. nov. species (1 C. minuta female from Tofino, British Columbia; 2 R. petersoni spec. nov. male from vicinity of Yuba Pass, California). 1 Eye group, anterior. 2 Patellae, tibiae, and metatarsi of legs I and II, ventral showing ventral tibial macrosetal pattern of 2(+1p)-2-2-2-2-0 on leg I and 2(+1p)-2-2-2-1-2-0 on leg II. AME—anterior median eyes, I—leg 1, II—leg II, Mt—metatarsus, Pt—patella, Ti—tibia.

FIGURES 3–7. Cybaeina species, males (3 C. confusa from Cascadia, Oregon; 4 C. confusa from unknown locality; 5 C. dixoni spec. nov. from Brookings, Oregon; 6–7 C. minuta from Kyuquot, British Columbia), left pedipalp. 3, 5–6 Genital bulb, ventral. 4, 7 Tegular apophysis and embolus, retrolateral. Cy—cymbium, DA—distal arm of tegular apophysis, E—embolus, PA—proximal arm of tegular apophysis, Ti—tibia, TR—tegular ridge.

FIGURES 8–13. Cybaeina species, males (8–9 C. confusa from Cascadia, Oregon; 10–11 C. dixoni spec. nov. holotype; 12–13 C. minuta from Kyuquot, British Columbia), left pedipalp. 8, 12 Tibia and distal portion of patella, retrolateral. 10 Tibia and patella, retrolateral. 9, 11 Tibia and patella, dorsal. 13 left half of patella, dorsal. Cy—cymbium, dRTA—distal component of retrolateral tibial apophysis, mRTA—medial component of retrolateral tibial apophysis, PTA—patellar apophysis, Ti—tibia. Note: in Figs 8–9 the mRTA terminates distally in a basally articulated macroseta; in Figs 10–12 the distal end is a short rigid spine-like process.

FIGURES 14–18. Cybaeina and Neocybaeina gen. nov. species, males (14–15 C. dixoni spec. nov. holotype; 16–17 C. minuta from Kyuquot, British Columbia; 18 N. xantha comb. nov. from near Bridge, Oregon), left pedipalp retrolateral. 14, 16 tibia and distal tip of patellar apophysis.15, 17 medial component of retrolateral tibial apophysis.18 distal tip of patellar apophysis.Arrows indicate medial component of retrolateral tibial apophysis (14–17 single shafted arrows), distal component of retrolateral tibial apophysis (14, 16 double shafted arrows), unknown contaminant on dorsal surface of patellar apophysis (18 dashed arrow).

FIGURES 22–27. Cybaeina species, females (22–24 C. minuta from Tofino, British Columbia; 25–27 C. dixoni spec. nov. from Brookings, Oregon), copulatory organ. 22, 25 Epigyne, ventral. 23–24, 26–27 Vulva (23, 26 ventral; 24, 27 dorsal). BG—Bennett’s gland, BS—base of spermatheca, CD—copulatory duct, HS—head of spermatheca, SS—stalk of spermatheca. Unlabelled arrows indicate atrial openings (22, 23, 25–26).