Siguanesiotes, Teruel, 2018

Teruel, Rolando, 2018, Two new genera and a new species of schizomids (Arachnida: Schizomida) from Isla de Pinos, Cuba, Ecologica Montenegrina 19, pp. 33-49 : 35-37

Siguanesiotes gen. n.

Figs. 1–2 , 6 . Table I

Schizomus [in part: references to S. insulaepinorum only]: Armas, 1977: 1–5, 8; figs. 1–2; tab. 1. Armas, 1984: 9. Armas, 1989: 1–2, 16–17, 30, 34, 36; figs. 3, 5d. Reddell & Cokendolpher, 1995: 6, 160–161. Harvey, 2003: 368.

Luisarmasius [in part: references to L. insulaepinorum only]: Reddell & Cokendolpher, 1995: 1, 12, 19, 81– 82, 140–141, 160; tabs. 2–3. Armas & Teruel, 2002: 45. Armas, 2004: 46. Harvey, 2003: 11, 368. Teruel, 2003: 40, 42. Teruel, 2007: 40, 51. Teruel, 2011: 12, 87. Armas & Alayón, 2014: 47–48. Teruel, 2017a: 46.

Type species. Schizomus insulaepinorum Armas, 1977 (= Siguanesiotes insulaepinorum [ Armas, 1977] comb. n.), by both present designation and monotypy.

Diagnosis. Size moderately large for the family (4–5 mm). Coloration: immaculate light olivaceous, with subtle shades of orange to yellow on pedipalps and body. Body without clavate setae. Cheliceral movable finger: ventrointernal margin with serrula and guard tooth, ventroexternal margin with a smooth lamella progressively stronger and angled distally. Pedipalps slightly sexually dimorphic and apparently not polymorphic: only slightly longer in males, which all seem heteromorphic; trochanter with internal spur. Propeltidium without true ocelli, but with ordinary eyespots instead; anterior process with two apical setae (1 + 1), dorsal setae sexually not dimorphic: 2–3 pairs (second submedian pair sometimes incomplete) in both males and females. Metapeltidium divided. Tergite I lacking anterior microsetae (present on II) and with posterior margin shallowly notched; tergites II–VII with setation unmodified and sexually not dimorphic: standard formula 2 / 2 / 2 / 2 / 2 / 2. Leg IV femur moderately robust, anterodorsal margin angled at essentially 90°. Male: pedipalp trochanter with femoral articulation on mediodorsal position (i.e., approximately horizontal to the trochanter longitudinal axis) and with apex strongly produced into a triangular flat projection; patella and tibia without strongly modified armature, only ventrodistally with thin, spiniform, paired macrosetae. Abdomen not attenuate, with setation slightly modified: segment XII with dorsoposterior pair of macrosetae modified (thickened and angled); segment XII unmodified, with posterodorsal process essentially absent. Flagellum broadly subpentagonal, much wider than deep and dorsally flat, pedicel/bulb angled roughly at 180°, but apex conspicuously raised upwards; pedicel short and compressed (much deeper than wide); bulb with dorsal surface lacking any conspicuous sculpturing, except for a pair of longitudinal submedian furrows all along; setation pattern: single dm 1, dm 4, vm 1 and vm 5, paired dl 2, dl 3, vm 2, vm 3, vl 1 and vl 2, with dl 1 minute, dm 1 located at pedicel-bulb junction and dm 4 in apical position; setation moderately modified: dm 4 and vl 1 enlarged, compressed and apically truncate, dl 3 displaced to ventral surface and vl 2 displaced medially. Female (no specimens available, data reinterpreted from Armas [1977] and Armas [1989: fig. 5d]): flagellum with three flagellomeres and two annuli; setation pattern unknown (not described). Spermathecae with three pairs of simple, subequal lobes: short, thick, club-shaped, lacking apical bulbs, and coarsely fenestrate, sometimes one outer lobe can be distally bifurcate. Chitinized arch well sclerotized, short and wide, subtriangular (i.e., with posterior branches straight and forming pointed lateral tips with anterior branches). Gonopod unknown (not described).

Comparisons. Siguanesiotes gen. n. must be compared first to Luisarmasius because this is the genus where its single species was placed. The former can be reliably distinguished by the following unambiguous characters:

1. Setation of tergite I: anterior microsetae absent. In Luisarmasius there are three pairs; see Camilo & Cokendolpher (1988: 57).

2. Shape and armature of pedipalp trochanter: apex strongly produced into a sharp triangular projection, internal spur located in standard subdistal position. In Luisarmasius the apex is not produced and the internal spur is displaced apically; see Camilo & Cokendolpher (1988: 57–58; fig. 10) and Reddell & Cokendolpher (1995: 153; fig. 62).

3. Shape of male flagellum: subpentagonal, without defined lateral lobes, dorsally with two submedian furrows which are long, shallow and medially convergent. In Luisarmasius it is obtusely trilobed, with clearly defined round lateral lobes and dorsally with two submedian circular depressions; see Reddell & Cokendolpher (1995: 153; figs. 63–65).

4. Setation of male flagellum: setae dm 4 and vl 1 enlarged, compressed and apically truncate, dl 3 displaced to ventral surface and vl 2 displaced medially. In Luisarmasius the setae dm 4 and vl 1 are not modified (thin, acuminate), dl 3 are located in standard dorsal surface and vl 2 are located in standard subapical position; see Camilo & Cokendolpher (1988: 57–58; fig. 10) and Reddell & Cokendolpher (1995: 153; fig. 62).

5. Structure of female spermathecae: lobes club-shaped, chitinized arch subtriangular, with posterior branches straight and forming pointed lateral tips with anterior branches; see Armas (1989: 16, 36; fig. 5d). In Luisarmasius the lobes are piriform, the chitinized arch is widely cordiform and lacks lateral tips due to evenly, roundly continuous anterior and posterior branches; see Camilo & Cokendolpher (1988: 58; fig. 12) and Reddell & Cokendolpher (1995: 153; fig. 61).

Among the remaining Neotropical genera, Siguanesiotes gen. n. most closely resembles Cokendolpherius Armas, 2002 by sharing similar habitus, coloration, shape and armature of male pedipalps, and especially by lacking anterior microsetae on tergite I (a very unusual character). But the latter can be easily distinguished from the former by: 1. Cheliceral movable finger with ventroexternal margin lacking armature (i.e., lamella or teeth). 2. Tergite I with posterior margin deeply notched. 3. Male flagellum narrowly trident-shaped in dorsal view (i.e., bulb with three very long, narrow and essentially parallel lobes) and with dm 4 seta located basally to medially on bulb. 4. Female spermathecae with two pairs of moderately long lobes.

Distribution (fig. 6). This genus is endemic to Isla de Pinos, with its single species restricted to three nearby, isolated, residual marble hills of the northeastern quadrant of the island.

Etymology. The selected epithet is an arbitrary combination of letters, mixing the original Taino toponym for Isla de Pinos (" Siguanea ") and the Latinized Greek name for an islander (" nesiotes "). The generic epithet is designed here of common gender; see Article 30.2.2 of the Code (ICZN, 1999: 37).

Figures

Fig. 1. Adult male holotype of Siguanesiotes insulaepinorum comb. n. (see accompanying labels and poor condition of this specimen): a) habitus, dorsal; b) habitus, lateral; c) pedipalps, lateral; d) abdominal segments IX–XII and flagellum, dorsal; e) abdominal segments IX–XII and flagellum, lateral.

Fig. 2. Adult male of Siguanesiotes insulaepinorum comb. n., from Sierra Chiquita (see fresh, perfectly preserved specimen): a) habitus, dorsal; b) habitus, lateral; c) pedipalps, lateral; d) abdominal segments IX–XII and flagellum, dorsal; e) abdominal segments IX–XII and flagellum, lateral.

Fig. 6. Geographical distribution of Siguanesiotes gen. n. and Siguanesiotes insulaepinorum comb. n.: previous records (red symbols), new record (yellow symbol). Image frame = 500 x 220 km, inset = 20 x 13 km. Fig. 7. Geographical distribution of Pinero gen. n. and Pinero marmoreus sp. n. (yellow symbols, the southernmost is the type locality). Image frame = 500 x 220 km, inset = 20 x 13 km.