Diguetia balandra, Jimenez & Cardiel & Chamé-Vázquez, 2022

Jimenez, Maria-Luisa, Cardiel, Carlos Palacios & Chamé-Vázquez, David, 2022, The spider genus Diguetia Simon, 1895 (Araneae: Diguetidae) in North America a new species, redescriptions, and comments on the distribution of the genus, Zootaxa 5205 (2), pp. 125-146 : 127-131

Diguetia balandra sp. nov.

Figs 1–29 , 109 .

Type material. ♂ Holotype from MEXICO: Baja California Sur: Municipality of La Paz, La Paz , Balandra Hill (24.32558°N, 110.32675°W, 73m), 26.IX.2018, leg. C. Palacios (CARCIB-Ar 0032) . Paratypes: same data as holotype, 19.IX.2017, 1♂ 9♀ (CARCIB-Ar 0209) ; same data as holotype, 3♀ 6imm. (CARCIB-Ar 0211) ; same data as holotype, 2♀ (CARCIB-Ar 0210) ; same data as holotype, 1♀ (CARCIB-Ar 0004) .

Etymology. The specific name is a noun taken from the type locality.

Diagnosis. Diguetia balandra sp. nov. resembles D. canities , D. dialectica stat. reval., and D. stridulans by having an opisthosoma with a middle dorsal band with two posterior scalloped white bands ( Figs 2, 6 ) but in D. canities these bands are flanked with darker bands ( Gertsch, 1958: fig. 1), in D. dialectica stat. reval. the scalloped bands are thin ( Figs 31, 35 , 59, 62 ), and in D. stridulans the opisthosoma has distinctive long, coarse setae. Moreover, D. balandra sp. nov. differs from D. canities and D. dialectica stat. reval. in the leg formula 4123 instead of 1423. The ring pattern of legs of D. balandra sp. nov. and D. dialectica stat. reval. are attenuate ( Figs 28–29 ; 54–55 ), while in D. canities it is well-marked, and the rings are absent in D. stridulans . Females of D. balandra sp. nov. have conspicuous long, thick macrosetae on metatarsus IV ( Figs 24, 29 ), while D. canities , D. stridulans , and D. dialectica stat. reval. have short and thin macrosetae as in other species. The membranous median sac of D. balandra sp. nov. and D. dialectica stat. reval. are similar, but the sac of the former is longer ( Fig. 10 ), while in D. canities the apical portion is subspherical ( Gertsch, 1958: fig. 18). Moreover, the male bulb prong in D. balandra sp. nov. is shorter (half the length of embolus, see Figs 13, 16 ) than in D. canities and D. dialectica stat. reval., which is more than half the length of the embolus ( Figs 42, 45 ; Gertsch, 1958: fig. 16). The embolus tip of D. balandra sp. nov. and D. canities are similar ( Figs 13, 16 , 17 ), as both lack the tip attenuated and bent as in D. dialectica stat. reval. ( Fig. 41 ).

Description. Male (holotype CARCIB-Ar 0032). Coloration: carapace and chelicerae dark yellow with scarce setae, fovea inconspicuous but with a depressed area from where two bands of white setae emerge towards the ocular area, carapace margins, and clypeus with white setae, eyes with black rings ( Figs 1 , 25 ). Endites pale yellow with scarce white setae and margins darker. Labium and sternum brown, the latter with margins dark and white setae ( Fig. 3 ). Legs I–IV light yellow, Fm I lighter proximally, Ti I, and Mt I darker than Fm I. Pt II and Ti II slightly darker, Ti II with a dark distal ring and Mt with darker sides. Pt III darker, Ti III, Mt III and Ta III with a dark distal ring. All segments of leg IV with dark distal ring ( Fig. 28 ). Dorsum and sides of opisthosoma greyish, covered with white and dark setae, dorsum with a longitudinal dark band, broadened posteriorly with a wavy margin and bordered more densely with white setae ( Fig. 2 ). Venter of opisthosoma dark brown, epigastric area darker, and spinnerets black ( Fig. 4 ). Habitus: carapace oval, cephalic region slightly narrower than thoracic region ( Fig. 1 ). Front face of chelicerae is very rugged, the stridulatory file occupies almost all lateral face. Promargin of chelicerae with a transparent lamina and two distal teeth; retromargin with three small teeth. Labium, endites and sternum longer than wide ( Fig. 3 ). Trochanters of all legs without notch; Ta and Mt without scopula; paired pectinate claws with ten teeth. Metatarsal lyriform organ with eight slits in dorsal view ( Fig. 21 ). Ta I with false sutures. Opisthosoma without caudal extension. Palp: Fm with three ventrolateral stridulating pins (arrow in Figs 11, 13 ), Ta with two finger-like processes, the prolateral one shorter ( Figs 11 , 17 ), the suboval bulb narrows apically (0.7 long, 0.3 wide; Figs 13–16 ), with spoon-shaped embolus (0.3 long) and straight tubular prong, half the length of the embolus (0.16 long) ( Figs 11–17 ). Measurements: total length 4.8; carapace 2.25 long, 1.37 wide; clypeus height 0.16; chelicerae length 0.56. Eye sizes and interdistances: AME 0.13, ALE 0.13, PME 0.13; AME–ALE 0.09, AME–PME 0.16. Length of legs segments: I 9.9 (3.0, 0.7, 2.9, 2.1, 1.2), II 8.8 (2.8, 0.6, 2.4, 2.3, 0.7), III 6.8 (2.2, 0.5, 1.6, 1.8, 0.7) IV 10.1 (3.2, 0.5, 2.6, 3.0, 0.8). Leg formula 4123.

Female (CARCIB-Ar 0004). Coloration: as the male but carapace and chelicerae light brown, the later with dark lateral sides ( Figs 5–8 ). Sternum, endites and labium darker than in male ( Fig. 7 ). Palps light yellow and black macrosetae. Legs I–IV light yellow, Pt I–IV darker than other segments; Ta I–IV and Mt I–IV darker distally. Fm IV and Ti IV with dark distal ring, Pt IV dark brown lateral sides, Mt IV dark-yellow with very long macrosetae ( Figs 24, 29 ). Dorsum and venter of opisthosoma as in male, although epigastric area with long black setae and hyaline setae ( Figs 6, 8–9 ). Front face of chelicerae is very rugged, the stridulatory file occupies almost all lateral face ( Fig. 20 ). Ta with dorsal slit sensilla ( Fig. 22 ) and dorsal capsulate tarsal organ ( Fig. 23 ). External genitalia: anterior sclerotization semicircular on anterior dark brown trapezoid pigmentation; posterior sclerotization represented by narrow strip ( Figs 8–9 ). Internal genitalia: two oval lateral pore plates heavily sclerotized, a wide uterus externus, a membranous median sac, which is slightly longer than wide, lies dorsally to the uterus ( Figs 10 , 18–19 ). Measurements: total length 6.4, carapace 2.3 long, 1.4 wide; clypeus height 0.26, chelicerae length 0.56. Eye sizes and interdistances: AME 0.13, PME 0.13, ALE 0.13, AME–ALE 0.9, AME–PME 0.19. Length of legs segments: I 7.8 (2.4, 0.8, 2.1, 1.7, 0.8), II 7.0 (2.1, 0.7, 1.9, 1.6, 0.7), III 5.6 (1.9, 0.6, 1.2, 1.4, 0.5), IV 9.0 (2.9, 0.7, 2.4, 2.5, 0.5).

Variation. Males (n=2) total length 3.9–4.1; carapace 2.0 long, 1.3–1.4 wide; clypeus height 0.2; chelicerae length 0.5–0.6. Length of legs segments: I 10.0–10.4 (3.0–3.1, 0.7–0.8, 3.0, 2.2–2.4, 1.1), II 8.5–9.3 (2.6–2.7, 0.6, 2.5, 2.3–2.4, 0.9-1.0), III 6.5–7.2 (2.1–2.2, 0.5, 1.5–1.8, 1.7–2.0, 0.6–0.7), IV 9.6–10.2 (3.0–3.2, 0.5–0.6, 2.6, 2.9–3.0, 0.6–0.8). Eye sizes and interdistances: AME 0.09, PME 0.13, ALE 0.13, AME–ALE 0.06–0.09, AME– PME 0.06–0.13 Females (n=11) total length 4.4–6.9, carapace 1.8–3.3 long, 0.8–1.8 wide; clypeus height 0.2– 0.3, chelicerae length 0.6–0.8. Length of legs segments: I 6.6–8.2 (2.3–1.9, 0.5–0.8, 1.7–2.3, 1.4–1.7, 0.7–1.5); II 6.1–8.3 (1.7–2.1, 0.6, 1.8, 1.5, 1.9, 1.6–1.7, 0.7–0.8), III 4.1–5.6 (1.3–1.8, 0.5–0.6, 0.7–1.2, 1.0–1.3, 0.6–0.7), IV 6.8–9.5 (2.1–2.7, 0.5–0.7, 1.8–2.4, 1.8–3.0, 0.6–0.7).AME 0.13–0.16, PME 0.09–0.13, ALE 0.13–0.19. AME–ALE 0.09–0.19, AME–PME 0.13–0.16.

Remarks. Live specimens of D. balandra sp. nov. have bodies covered with white setae, which usually fall off after capture (see Fig. 25 ). Diguetia stridulans was described on the basis of a single female from Mejía Island, Baja California (currently deposited at CAS collection). According to Chamberlin (1924: 590–591) and Gertsch (958: 24) this is a distinctive species that readily separated it from other species as mentioned above (diagnosis). Furthermore, the ratio of the first leg to the carapace of D. stridulans is longer than in the other species, and the stridulating file on chelicerae is composed of fine and coarse striae ( Chamberlin 1924, Gertsch 1958). The holotype is in poor condition ( Gertsch 1958: 24) and needs further study, but the characters above allow us to distinguish it from D. balandra sp. nov..

Distribution. Known only from the type locality (See Fig. 109 ).

Natural history. Diguetia balandra sp. nov. is found on hills near the seashore ( Fig. 106 ) where they spin tiny webs between rocks and low vegetation in sarcocaule shrublands ( Fig. 27 ). Due to the small web, which are built 5 cm above the ground (mean distance) with retreats covered with sandy material, and small corporal size, D. balandra sp. nov. is usually imperceptible ( Fig. 26 ). The web is characteristic of Diguetia . It has a polyhedron form with four irregular sides and consists of a horizontal silk sheet with irregular tangles of threads above and below the sheet. At the center there is a vertical inverted cone-shaped retreat covered with numerous sand grains adhered with silk, which is closed at the top and open at the bottom. Female retreat size: 13.8–19.4 high and 2.24–6.5 wide at bottom (n=8), males: 12.5–15.5 high and 4.7–5.2 wide at bottom (n=2). This retreat is held up at the top by thick silk threads adhered to the adjacent rocks; the lower side attached to the horizontal silk sheet. The retreat exterior is covered with sandy grains while the interior is covered with a thick layer of silk, which is thicker in females retreat (like a spongy mesh) than males. The lenticular egg sacs (2–4) are sheltered inside and line up from the bottom to the top, and usually placed in one side of the retreat. Males and females rest inside during the day covering the entrance with the opisthosoma.

Figures

FIGURES 1–10. Diguetia balandra sp. nov. 1, 2, male habitus, dorsal; 3, 4, same, ventral; 5, 6, female habitus, dorsal; 7, 8, same, ventral; 9, female genitalia, ventral; 10, same, dorsal. Scale bars 1–8: 0.50 mm; 9–10: 0.20 mm.

FIGURES 11–16. Diguetia balandra sp. nov. 11, male palp (arrow pointing stridulating pins), prolateral; 12, same, retrolateral; 13, same (arrow pointing stridulating pins), dorsal; 14, same, slightly off views “prolateral”; 15, same, slightly off views “retrolateral”; 16, cleared male palp, dorsal. Scale bars 11–16: 0.20 mm.

FIGURES 17–29. Diguetia balandra sp. nov. 17, male palp, dorso-lateral; 18, female genitalia, ventral; 19, detail of lateral pore plates, dorso-lateral; 20, female stridulating file of chelicerae, lateral; 21, male metatarsal lyriform organ; 22, female tarsal slit sensilla; 23, female, tarsal organ of leg I; 24, metatarsus IV of female, lateral; 25, live male specimen; 26, retreat in situ; 27, web in situ; 28, male leg IV, prolateral; 29, female leg IV, prolateral. Scale bars 28–29: 0.50 mm

FIGURES 109–110. Records of North American Diguetia species.

FIGURES 30–39. Diguetia dialectica stat. reval. 30, 31, male habitus, dorsal; 32, 33, same, ventral; 34, 35, female habitus, dorsal; 36, 37, same, ventral; 38, female genitalia, ventral; 39, same, dorsal. Scale bars 30–37: 0.50 mm; 38–39: 0.20 mm.

FIGURES 56–66. Diguetia dialectica stat. reval., 56–58 female holotype, 59–66 specimens studied by Gertsch (1958: 13– 14). 56, 59, female habitus, dorsal; 57, 60, same, ventral; 58, 66, female genitalia, ventral (inset specimens labels); 61, male habitus, lateral; 62, same, dorsal; 63, same, ventral; 64, male palp, slightly off views “prolateral”; 65, same, slightly off views “retrolateral”. Scale bars 56–63, 66: 0.50 mm; 64–65: 0.20 mm. Note: Figs 56–58 (including label) by the California Academy of Sciences used under CC BY-NC-SA 4.0; 64–65 by Museum of Comparative Zoology, Harvard University.

FIGURES 46–55. Diguetia dialectica stat. reval. 46, male palp, dorso-lateral; 47, female genitalia, ventral; 48, detail of lateral pore plates, dorso-lateral; 49, female metatarsal lyriform organ; 50, tarsal organ and sensilla of male leg I, dorsal; 51, web in situ; 52, retreat in situ; 53, live female specimen; 54, male leg IV, prolateral; 55, female leg IV, prolateral. Scale bars 54–55: 0.50 mm.

FIGURES 40–45. Diguetia dialectica stat. reval. 40, male palp (black arrow pointing stridulating pins), prolateral; 41, same, retrolateral; 42, same (blue arrow pointing bulged part of bulb), dorsal; 43, same, slightly off views “prolateral”; 44, same, slightly off views “retrolateral”; 45, cleared male palp (arrow pointing bulged part of bulb), dorsal. Scale bars 40–45: 0.20 mm.

FIGURES 103–108. 103–105. Diguetia imperiosa. 103, live female specimen; 104, live male specimen; 105 web in situ; 106–108. Diguetia habitats. 106, Habitat of D. balandra sp. nov. at Balandra Beach, Baja California Sur, Mexico; 107, Habitat of D. dialectica stat. reval. at Sierra La Gata, Baja California Sur, Mexico; 108, Habitat of D. dialectica stat. reval. and D. imperiosa at San Basilio, Baja California Sur, Mexico.