Charinus insularis Banks, 1902

Figs 1–2, 34, 36–41; Table 3

Charinus insularis Banks, 1902: 67, 68, pl. 2 fig. 8.

Charinus insularis – Snodgrass 1902: 79–80. — Mello-Leitão 1931: 54. — Werner 1935: 471. — Dunn 1949: 7. — Roth & Craig 1970: 119. — Weygoldt 1972b: 123. — Stockton 1976: 57–61, figs 1–4. — Delle Cave 1986: 156, fig. II. — Peck & Kukalova-Peck 1986: 165. — Peck & Peck 1986: 44–46. — Hernández Pacheco et al. 1992: 89, 125, 133, 135, 141, 146, 149–150, 154, 158, 167. — Baert et al. 1996: 13–16, fig. 7, map 4. — Harvey 2003: 5–6. — Miranda & Giupponi 2011: 62, 67, fig. 13. — Jocqué & Giupponi 2012: 55. — Vasconcelos et al. 2013: 497. — Baert & Mahnert 2015: 2–3, 8–13, 70–71, 73–74, fig. 3. — Miranda et al. 2016c: 19, 31.

Diagnosis

This species may be separated from other Charinus in western South America by means of the following combination of characters: well-developed median eyes and median ocular tubercle (Fig. 36A); female gonopods cushion-like with small acute projection at apex of dorsal flap (Fig. 37E–F); male gonopod with thin, fimbriate lateral lobe 2 (Fig. 38A–B, D); dorsal lobe with acute spiky projections (Fig. 38A– D, F); cheliceral claw with seven teeth and short row of setae on retrolateral view (Fig. 39D).

Etymology

Although unspecified in the original description, the species name evidently refers to the provenance of this species on an island, in this case the Galapagos Islands, to which it appears to be endemic.

Type material

Syntypes ECUADOR • Galapagos Islands: Albemarle Island (as Isla Isabela); [repository unknown] • Narboro Island; [repository unknown] • Chatham Island; [repository unknown] • Hood Island; [repository unknown] [not examined].

Additional material

ECUADOR • 1 protonymph; Galapagos Islands; RBINS 26445/23.2.6 • 1 ♀, 1 exuvium; Galapagos Islands; 17 Feb. 1986; RBINS 27047 • 1 ♀, 1 subad. ♂; Galapagos Islands, Turtle Bay, Isla de Santa Cruz; 14 Jan. 1965; J. and N. Leleup leg. • 1 ♀ [most legs and one pedipalp detached]; in crevice at foot of ravine, 1200 m from beach; RBINS • 1 ♀, 1 ♂; Isla de Santa Cruz; 17 Feb. 1965; J. and N. Leleup leg.; entrance of cave, under stone on clay [label indicates 2 ♀♀ and 1 juv., but vial contains only two specimens, one juvenile and another slightly larger, both with opisthosoma detached, hence impossible to determine sex of specimens]; RBINS • 1 ♀, 2 juv. ♂♂; Española crest; 26 Apr. 1992; 25 m a.s.l.; S. Peck and J. Cook leg.; under Opuntia Miller, 1754 bark and rocks; RBINS 92-143 • 1 ♀, 2 juv.♀♀, 2 juv. ♂♂; 1988; L. Baert, K. Desender and J.P. Maelfait leg.; RBINS 27318 • 1 ♀, 1 juv. ♂; RBINS 26445/23.2.1 • 2 juv. ♀♀, 2 juv. ♂♂; Isla de Santa Cruz, 800 m from pier of St Darwin; Dec. 1964; J. and N. Leleup leg.; at bottom of deep crevice (10 m); under rubble stone with soil and wet sand; RBINS • 1 ♀, 6 juv.; Isla de Santa Cruz; 17 Nov. 1964; J. and N. Leleup leg.; volcanic cave, 3.5 km N of Puerto Ayora village; RBINS • 1 ♀, 2 juv. ♂♂, 1 protonymph; Cueva Bellavista, Isla de Santa Cruz; 160 m a.s.l.; 22 Jan. 1989; S. Peck et al. leg.; RBINS • 1 juv.; Santa Fé; Oct. 1964; J. and N. Leleup leg.; RBINS • 1 ♀; Bellavista, Isla de Santa Cruz; 150 m a.s.l.; S. Peck leg.; bottle traps in caves; RBINS 96–97 • 1 ♀; Puerto Ayora, Isla de Santa Cruz; 28 Dec. 1991; S. Abedrabbo leg.; RBINS • 2 ♀♀; Hornemeu Farm, Isla de Santa Cruz; 250 m a.s.l.; Nov. 1964; J. and N. Leleup leg.; RBINS • 4 juv. ♀♀; RBINS 768 • 1 ♀ juv.; Pampa, 36 km from coast, Isla de Isabela; 600–1000 m a.s.l.; Nov. 1964; J. and N Leleup; RBINS • Isla de Santa Cruz; 1 km from coast; 20 m a.s.l.; Feb. 1965; J. and N. Leleup leg.; inside cave; RBINS .

Supplementary description

CARAPACE. Six anterior setae (Fig. 36A); frontal process triangular (Fig. 37D), not visible in dorsal view. Small granules, densely scattered between ocular triads and among sulci (Figs 36A, 37A–D). Median eyes present; median tubercle shallow (Fig. 37D); one pair of setae on median ocular tubercle; lateral eyes well developed, with seta posterior to lateral ocular triad (Fig. 37B)

STERNUM. Tritosternum projected anteriorly, with typical setation (Fig. 36B); other sternal platelets divided, concave, with one seta on each side of platelets and smaller setae posteriorly (Fig. 37B); pentasternum with four setae anteriorly and seta on membranous region (Fig. 37B).

OPISTHOSOMA. Ventral sacs and ventral sac cover absent.

GENITALIA. Female genital operculum with prominent setae posteromedially and some smaller setae near margin (Fig. 37E); gonopod cushion-like, flat, with projection on apex of retrolateral side of fold (Fig. 37E–F); base of gonopods sclerotized. Male gonopod markedly sclerotized at base of fistula and lateral lobe; lateral lobe 2 not fimbriate.

CHELICERAE. Small tooth projecting from retrolateral surface of basal segment, opposite to bifid tooth (Fig. 39A–G); retrolateral surface of claw with small patches of setae basally and medially (Fig. 39D– E); claw with seven teeth; transverse row of around eight setae on prolateral surface of basal segment; bifid tooth on basal segment with dorsal cusp larger than ventral cusp; setae on basal segment with acute apex and serrate margin (Fig. 39F), setae on claw with mop-like apex (Fig. 39G); hinge between basal segment and cheliceral claw with multiple slit sensilla (Fig. 39C).

PEDIPALPS. Coxal dorsal carina with three setae encircled by round carina and four setae on margin. Femur with four dorsal spines and four ventral spines (Figs 2, 36C–D, 40A–D); two prominent setiferous tubercles between dorsal spine 1 and proximal margin; spine between ventral spine 1 and proximal margin (Fig. 2). Patella with four dorsal spines in primary series (Fig. 36C–D); prominent setiferous tubercle distal to spine I, one-third length of spine I; two ventral spines in primary series (Fig. 2); prominent setiferous tubercle between spine I and distal margin. Tibia with ventral spine distally and two or three setae between spine and distal margin (Figs 2, 36D). Tarsus with two dorsal spines, proximal spine one-third length of distal spine; cleaning organ with 27–30 setae in ventral row. Spines with gland openings (Fig. 40D).

LEGS. Tibia of leg I with 23 articles (up to 29 in regenerated legs); tarsus I with 43 articles (up to 53 in regenerated legs); first tarsal article similar in length to subsequent articles; slit sensilla present on tarsal article 21. Leg IV patella with pair of trichobotria dorsally; surface surrounding trichobothrial insertions filled with erect scales (Fig. 41A). Leg IV basitibia with four pseudo-articles, with sclerotized, denticulate margin at apex of articles; trichobothrium bt situated in proximal third of pseudo-article; distitibia trichobothrium bc situated slightly closer to sbf than to bf, sc and sf series each with five trichobothria. Leg IV tarsus with projection between claws similar in length to last tarsal article; arolium microstructures with linear pattern at lip (Fig. 41C–D), randomly scattered at truncus (Fig. 41C, E).

Measurements

See Table 3.

Distribution

This comparatively large species is endemic to the Galapagos archipelago, and has been recorded on several islands (Baert & Mahnert 2015).

Natural history

Found inside and outside caves in cave entrances, ravines, under stones and rubble.

Remarks

The type material was collected during the Hopkins Stanford Galapagos Expedition, but the original description does not specify where the material is deposited. According to Dunn (1949), the type specimens may be in the collection of the Stanford University, California, but cannot be located.

The opisthosoma of the subadult male (the only male examined) is wrinkled and the genitalia distorted, hence impossible to describe. The large female specimen from Española (RBINS 92-143) appears to be adult, but has duplicate trichobotria (2 sbf, 2 bc and 2 bt), a character thus far known to occur only in juveniles (Weygoldt 2000a).

Miranda & Giupponi (2011) misinterpreted the female gonopod of C. insularis, stating it is sucker-like. However, the species has a cushion-like gonopod with an acute apical projection (Fig. 37E–F).