Caribbiantes barbai, Barroso & Pérez-González, 2024

Barroso, Aylin Alegre & Pérez-González, Abel, 2024, Two new species of Caribbiantes, with the redescription of the type species and a review of male genital patterns in Antillean Stenostygninae (Opiliones: Laniatores: Biantidae), Zootaxa 5514 (5), pp. 401-430 : 417-424

Caribbiantes barbai sp. nov.

urn:lsid:zoobank.org:act:06118480-8423-403D-8B64-336E3F6C73E6

( Figs. 9–11 )

Type series. Holotype ♂ (α) ( CZACC 3.4380 ), Trail to the lagoon of Monte Iberia , Alejandro de Humboldt National Park (PNAH), Baracoa Municipality, Guantánamo province, Cuba (20º27'27''N; 74º43'35''W), approximately 500 m a.s.l., under bark of living tree, 15.i.2009, R. Barba coll.. Paratypes: 1 ♀ ( CZACC 3.4380 , in the same vial as the holotype) ; 1 ♂ ( CZACC 3.3391 ), same data as the holotype ; 1 ♀ ( CZACC 3.3393 ), Río Piloto , Moa, Holguín province, Cuba (20º25'50.16''N; 74º53'08''W), 1.x.1996 (no coll.) ; 1 ♂ ( CZACC 3.3392 ), Toldo , Moa, Holguín province, Cuba (20º26'33.2''N; 74º51'36.9''W), collected in yellow dish trap on the ground, 4.x.1996, N. Viñas Dávila coll.

Etymology. The specific name is a genitive in honor of the Cuban arachnologist René A. Barba Díaz, who collected the holotype.

Diagnosis. This species differs from congeners in its somewhat ovoid body shape versus the sub-rectangular shape of C. cubanus and C. obtusus ( Figs. 9A ; 1A ; 6A ). Legs are longer than in C. cubanus , but shorter than in C. obtusus . It also differs in the armature of the mesotergal areas and free tergites: areas III and IV bear stronger spiniform apophyses than C. cubanus and C. obtusus ( Figs. 9C ; 1B ; 6C ). Free tergite III has a pair of low acute tubercles, instead of the strong acute spiniform apophyses as in C. cubanus or the blunt spiniform apophyses as in C. obtusus ( Figs. 9C ; 1B ; 6C ). Femora II–IV bear an acute dorsodistal apophysis ( Figs. 9A, B ), unlike C. cubanus and C. obtusus , in which femora are unarmed. Swollen region of metatarsus III of males is located in the third (subdistal) quarter of the segment but it reaches the second and fourth quarters too ( Fig. 10A ) (swelling is more restricted in C. cubanus and C. obtusus , centered between the third and fourth distal quarter, and not reaching the second basal quarter) ( Figs. 3A ; 7A ). The ventral groove may have 26–32 brush-like setae. Tarsal formula 7(3):12–15(4–6):8:8. Caribbiantes barbai sp. nov. is also clearly distinguishable from C. cubanus and C. obtusus by the morphology of the penis. The stragulum seen from dorsal view has a shallow cleft ( Figs. 11A, B, G ), similar to C. cubanus , but the distal end has thicker ledges ( Figs. 11B, G ) than in C. cubanus and C. obtusus ( Figs. 5A, G, H ; 8A, G ). The capsula interna has a lateroapically flattened stylus, longer and with a much more pointed tip than C. cubanus and C. obtusus ( Figs. 11E ; 5E ; 8E ). The two conductors, fused at the base, bear apical laminar lobes, ventrally projected ( Figs. 11E, I, J ), although they are much more rounded and dilated than in C. cubanus ; in contrast, they are blunt in C. obtusus ( Figs. 5E ; 8E, H ). Pars distalis with a ventroapical process in the form of a broad-based hook ( Fig. 11D ), much sharper than in C. cubanus and C. obtusus ( Figs. 5D ; 8D ).

Description of the holotype male (CZACC 3.4380) (microstructures observed by compound microscope and S.E.M. correspond to males CZACC 3.4380 and CZACC 3.3392).

Measurements: Table 3

Dorsum ( Figs. 9 A–D ): Dorsal scutum sub-rectangular, with anterior and posterior margins slightly narrower, giving it an ovoid appearance ( Figs. 9A, B ); in lateral view, the region of mesotergal areas is domed, with the highest point at the level of area III ( Figs. 9C, D ). Anterior margin of the dorsal scutum with shallow cheliceral sockets, and a row of seven small granules on each side, arranged close together ( Fig. 9A ). Carapace densely granulous, granules more visible laterally and in front of each eye ( Figs. 9C, D ). Eye mounds near sulcus I, projected laterally and covered by granules ( Figs. 9A, C ). Lateral margins of dorsal scutum with two rows of small tubercles, larger on the outer row, with increasing size towards the posterior margin ( Fig. 9A ). Four well-defined mesotergal areas, densely granulous, with wide sulci between them. Area I medially constricted, divided into triangular halves by a short and shallow median groove, each half bearing two slightly taller tubercles ( Figs. 9A, B ). Area II with two pairs of slightly taller lateral tubercles ( Figs. 9A, B ). Areas III–IV with a pair of strong, equal-sized spiniform and divergent apophyses, with bulky tuberculate bases ( Figs. 9C, D ). Area V and free tergites I–II with a row of small sharp tubercles. Free tergite III with a paramedian pair of strong acute tubercles ( Figs. 9A–D ). Anal operculum granulous ( Figs. 9C, D ).

Venter: Coxae covered by setiferous granules. Coxa I with an anterior row of small setiferous tubercles. Coxae III–IV with an anterior row of small tubercles that form small bridges with the posterior margin of the preceding coxa. Free sternites with a row of small tubercles. Genital operculum short and narrow.

Chelicerae: Basichelicerite with robust and well-marked bulla. Hand strongly swollen (hypertelic), with scattered setiferous granules, and longer setae towards the distal border ( Figs. 9C, D ). Fixed finger distally with five minute teeth, movable finger with a strong, blunt basal tubercle, followed by a smooth gap, a “dome-like” serrated curvature of the internal finger edge and distally 7–8 small teeth. Cheliceral fingers curved, leaving a wide basal gap when closed.

Pedipalps: Elongated, with large spines concentrated on tibia and tarsus. Coxa elongated, dorsally with one small ectoproximal acute tubercle, a group of four mesoproximal tubercles on a small protuberance, and one small distal tubercle; ventrally, a group of 3–4 proximal tubercles, followed by a distal setiferous tubercle. Trochanter dorsally granulous, ventrally with a proximal setiferous tubercle, followed by one subdistal setiferous tubercle and one distal granule. Femur with six spaced small setiferous granules on the dorsal surface, and four spaced small setiferous granules on the ventral surface. Patella dilated on its distal third, dorsally granulous and with a strong mesodistal spine. Tibia and tarsus dorsally granulous, more densely in tibia. Both segments ventrally armed with strong spines as follows: tibia ectal IIIi (1<2=3>4), tibia mesal IIII (1<2<3<4); tarsus ectal IiIi ((1>3)>2 =4)), tarsus mesal IiIi ((1>3)>2=4)). Tibia also with a ventral row of 4–5 small medial setiferous tubercles. The ectodistal spine on the tibia is very close to the preceding one, giving the appearance of being fused at their bases; the mesal spines on the tibia are equidistant from each other, resulting in similar-sized gaps in the spine series, as in C. cubanus and C. obtusus sp. nov. The mesoproximal spine on the tibia is located almost ectally. Tarsal claw robust, with almost the same length as the tarsus.

Legs: Covered by fine setiferous granules. Coxa IV covered by setiferous granules. Trochanters II–IV dorsally with granules. Femora II–IV with a distal spiniform apophysis ( Figs. 9A, B ). Patella IV with a medial dorsodistal small acute process. Metatarsus III spindle-shaped, with the swollen sector located in the third (subdistal) quarter of the segment but also reaching the second and fourth quarters ( Fig. 10A ). Ventral surface of the swollen region with wide, deep groove, buttonhole-shaped and bearing 31 long setae ( Figs. 10B, C ); setal shafts basally striated and twisted, distally enlarged in the shape of long paint brushes (lanceolate-shape) (distally dilated as in C. cubanus ) ( Figs. 10D, E ). Setae longitudinally arranged in two parallel alternating rows ( Fig. 10C ); numerous pores (glandular openings) regularly scattered around the base of the setae ( Fig. 10E ); integument adjacent to setae wrinkled and with shallow grooves between pores and setae ( Fig. 10E ). Two smooth tarsal claws, perpendicular to the leg axis. Distitarsi III–IV with scopula. Tarsal formula: 7(3):13–15(5–6):8:8.

Penis ( Figs. 11A–J ) (holotype male CZACC 3.4380; male paratype CZACC 3.3392 for S.E.M.): Larger than the remaining Caribbiantes species. In lateral view the dorsoapical portion is much bulkier than in other Caribbiantes species ( Figs. 11C, D ). Glans with a large stragulum that articulates dorsodistally with the trunk like a jackknife ( Figs. 11D, E, I ). Stragulum apically wide in dorsal view, with a wide cleft and thickened distal ledges, as well as numerous wrinkles in the transition with the truncus ( Figs. 11A–B, G ). Everted stragulum exposes its ventral extension in the form of the spiny follis and capsula interna ( Figs. 11E, H–J ). Capsula interna with a lateroapically flattened and wide stylus, very sharp towards its apical tip (lanceolate form), and two conductors fused at the base ( Fig. 11E ). Conductors are medially thin, with apical portion in the form of a laminar lobe, much dilated and rounded, projected ventrally ( Figs. 11E, H–J ). Stylus largely exceeds the length of the conductors and bears a very sharp and narrow tip ( Figs. 11B, E ). Pars distalis exhibits on the ventral side an apical process, wide at its base and sharp at the end (hook-shaped) ( Figs. 11D–E, I ), along with five pairs of ventral setae ( Figs. 11F, J ). Apical-most pair of setae notably minute and bifurcated, subapical pair of setae longer; the three pairs of ventrolateral setae are much longer than the subapical pair of setae, broad-foliar shaped, and arranged in two oblique rows ( Figs. 11E–F, I–J ).

Coloration (in 70% ethanol; Figs. 9B, D ): Dorsum reddish-brown, with some yellowish areas; a dark brown line borders the anterior margin and the cheliceral sockets. Brown reticulate marks anterolaterally on the carapace, leaving the median and the posterior median (next to area I) sectors of the carapace yellowish. Lateral margins with irregular brown marks. Areas I–II brown, with yellowish spots. Areas III–IV with brown reticulated marks and yellowish spots. Spiniform apophyses on areas III–IV dark brown. Posterior margin and free tergites dark brown, with yellowish spots on the tubercles. Legs brown, with a striped pattern of irregular yellowish spots. Chelicerae yellowish with brown reticle; fingers yellowish-brown. Pedipalps pale brown with yellow stripes, distal segments yellowish.

Female paratype (CZACC 3.4380). Similar to male, but slightly slenderer. Free tergite III with four small tubercles between the pair of spiniform apophyses. Chelicerae small, non hypertelic, without a gap between the cheliceral fingers as in α males; fixed and movable fingers with six distal teeth. Legs III–IV with femur, patella, and tibia slightly thinner than in males; metatarsus III not enlarged. Femora II–IV with a distal spiniform apophysis, as in the male. Coloration pattern as in males. Genital operculum wider than the male. Tarsal formula: 7(3):12(4):8:8. Measurements: Table 3 .

Variability. Males (n=3); females (n=2). Measurements in Table 3 . Cheliceral dentition: fixed finger with 5–7 distal teeth, movable finger with 6–8 distal teeth. In the swollen region of metatarsus III each studied male had a different number of setae (26, 31, 32). The tarsal formula varies only in leg II: 7(3):12–15(4–6):8:8. Hypertelic chelicerae in only two studied males (α males—including the holotype); one male has small chelicerae (ss male).

Distribution. This species has the eastern-most records for the genus. It is likely a Cuban short-ranged endemic, so far restricted to three localities in Toldo and Monte Iberia Plateaus (Holguín and Guantánamo provinces, respectively) ( Fig. 12A ).

Natural history. This species was collected under the bark of living trees, in the sub-montane rainforest at 500 m a.s.l. ( Figs. 12B ).

Figures

FIGURE 1. Caribbiantes cubanus, habitus: A–B, holotype, α male (MCZ IZ-14702). A. dorsal view; B. lateral view; C–D, β male (CZACC 3.3380). C. dorsal view; D. lateral view. Scale bars = 1 mm.

FIGURE 3. Glandular structure of male metatarsus III in Caribbiantes cubanus. A. Light microscope photo, male (CZACC 3.4372), general view of the whole metatarsus III (divided into four quarters to facilitate comparisons); B–E., Scanning electron micrographs, male (CZACC 3.3266): B. View of the glandular swelling, dashed line delineates the form of the ventral, buttonhole-like groove; C. Close-up of the groove delimited in B, note its depth; D. Closer zoom into the groove, white arrow indicates a seta (long paint brush, basally striated and twisted), small arrowheads point to glandular openings (pores) irregularly arranged around the setae; E. Detail of the integument of the ventral groove.

FIGURE 5. Caribbiantes cubanus, entire (C) and distal part (A–B, D–I) of penis,A–F. Drawings with optical microscope (male CZACC 3.3379): A. Dorsal view; B. Dorsal view expanded; C. Ventral and lateral views (entire penis); D. Left lateral view; E. Left lateral view expanded (with enlarged detail); F. Ventral view. Scale bars = 0.1 mm; G–I. Scanning electron micrographs (male CZACC 3.3266): G. Dorsal view; H. Left lateral view; I. Ventral view.Abbreviations:AP, apical process; AS, apical setae; CI, capsula interna; Clf, cleft; Co, conductors; Fo, follis; Led, ledge; Str, stragulum; Sty, stylus; VLS, ventrolateral setae.

FIGURE 6. Caribbiantes obtusus sp. nov., habitus of male holotype (CZACC 3.3384): A–B. Dorsal view; C–D. Lateral view. Scale bars = 1 mm.

FIGURE 7. Glandular structure of male metatarsus III in Caribbiantes obtusus sp. nov. (male CZACC 3.4379). A. Light microscope photo, general view of the whole metatarsus III (divided into four quarters to facilitate comparisons); B–E. Scanning electron micrographs: B. View of the glandular swelling, dashed line delineates the form of the ventral, buttonhole-like groove; C. Close-up of the groove delimited in B, note the depth of the groove; D. Closer zoom into the groove, arrows show setae (long paint brush, basally striated and twisted); E. Integument of the ventral groove, white arrowheads indicate glandular openings (pores) irregularly arranged around the setae.

FIGURE 8. Caribbiantes obtusus sp. nov., entire (C) and distal part (A–B, D–J) of penis. A–F: Drawings with optical microscope, male holotype (CZACC 3.3384), A. Dorsal view; B. Dorsal view, expanded; C. Ventral and lateral views (entire penis); D. Left lateral view; E. Left lateral view expanded (with enlarged detail); F. Ventral view. Scale bars = 0.1 mm. G–J. Scanning electron microscopy male CZACC 3.4379). G. Dorsal view; H. Apical view (apical portion of a conductor colored in pink); I. Ventrolateral view; J. Ventral view. Abbreviations: AP, apical process; AS, apical setae; CI, capsula interna; Clf, cleft; Co, conductors; Fo, follis; Led, ledge; Str, stragulum; Sty, stylus; VLS, ventrolateral setae.

FIGURE 9. Caribbiantes barbai sp. nov., habitus of male holotype (CZACC 3.4380): A–B. Dorsal view; C–D. Lateral view. Scale bars = 1 mm.

FIGURE 10. Glandular structure of male metatarsus III in Caribbiantes barbai sp. nov. A. Light microscope photo, holotype male (CZACC 3. 4380), general view of the whole metatarsus III (divided into four quarters to facilitate comparisons); B–E. Scanning electron micrographs, male (CZACC 3.3392); B. View of the glandular swelling, dashed line delineates the form of the ventral, buttonhole-like groove; C. Close-up of the groove delimited in B, note the depth of the groove; D. Closer zoom into the groove, white arrow shows a seta (long paint brush, basally striated and twisted), small arrowheads indicate glandular openings (pores) regularly arranged around the setae; E. Detail of the integument and pores (arrowheads) of the ventral groove.

FIGURE 11. Caribbiantes barbai sp. nov., entire (C) anddistal part (A–B, D–J) of penis,A–F.Drawings with optical microscope, male holotype (CZACC 3.4380): A. Dorsal view; B. Dorsal view, expanded; C. Ventral and lateral views (entire penis); D. Left lateral view; E. Left lateral view, expanded (with enlarged detail); F. Ventral view. Scale bars = 0.1 mm. G–J. Scanning electron micrographs (male CZACC 3.3392): G. Dorsal view, expanded; H. Apical view, expanded; I. Left lateral view, expanded; J. Ventral view, expanded.Abbreviations: AP, apical process; AS, apical setae; CI, capsula interna; Clf, cleft; Co, conductors; Fo, follis; Led, ledge; Str, stragulum; Sty, stylus; VLS, ventrolateral setae.

FIGURE 12. Records and habitat of Caribbiantes spp. A. Map of Cuba (general and expanded sector as indicated), showing known localities of Caribbiantes cubanus (circles, type locality in red); C. obtusus sp. nov. (triangles, type locality in red) and C. barbai sp. nov. (squares, type locality in red); B. Submontane rain forest in Alejandro de Humboldt National Park, Monte Iberia, type locality of C. barbai sp. nov.; C. Mountains of Topes de Collantes, Sancti Spíritus province, record of C. cubanus and C. obtusus sp. nov.