Cazierius cayacoa, Teruel & Jiménez & Santos, 2021

Teruel, Rolando, Jiménez, Solanlly Carrero & Santos, Gabriel de los, 2021, The first troglobitic scorpions from Hispaniola, Greater Antilles: two new species of Cazierius Francke, 1978 (Scorpiones: Diplocentridae), Euscorpius 340, pp. 1-9 : 2-4

Cazierius cayacoa sp. n.

( Figures 1 , 3–4 ) http://zoobank. org/urn:lsid:zoobank. org:act:B1E5C590-

FE37-483D-9770-B80EC2FCFA30

TYPE LOCALITY AND TYPE REPOSITORY. Dominican Republic, San Pedro de Macorís Province, Ramón Santana Municipality, Monumento Natural Río Cumayasa y Cueva de las Maravillas , Cueva de las Maravillas , 18°27'06.1"N 69°09'38.6"W, 40 m a. s. l. , MNHNSD.

TYPE SPECIMENS. Dominican Republic, San Pedro de Macorís Province, Ramón Santana Municipality, Monumento Natural Río Cumayasa y Cueva de las Maravillas, Cueva de las Maravillas 18°27'06.1"N 69°09'38.6"W, 40 m a. s. l., 14–18 October 2001, no collector specified, 1 juvenile ♂ holotype ( MNHNSD 08.442 ) . ADDITIONAL MATERIAL EXAMINED (not types). Dominican Republic, San Pedro de Macorís Province, Ramón Santana Municipality, Monumento Natural Río Cumayasa y Cueva de las Maravillas , Cueva de las Maravillas (18°27’06.1”N 69°09’38.6”W), 40 m a.s.l., 18 September 2016, leg . R. Teruel, F. Schramm, 2 adult chelae ( RTO).

ETYMOLOGY. The selected epithet is a Latinized patronym in apposition, taken straight from the name of the last Taino cacique that ruled the Higüey Chiefdom, which included the area where the type locality of this species is enclaved. Cayacoa was the second most powerful cacique of Hispaniola.

DIAGNOSIS (based on holotype juvenile male only). Habitus fully troglomorphic: entire animal depigmented (coloration translucent, immaculate pale whitish-yellow to beige), pedipalp, legs and metasoma conspicuously attenuated, carapace lacking median ocular tubercle and eyes (without any traces of lens and ocular pigment), trichobothria with shaft exaggeratedly long, thin and flexible, and telson with vesicle enlarged. Legs with modal formula of telotarsal spiniform setae 3/3: 4/4: 5/5: 5/5. Pectines with 6/6 teeth.

DESCRIPTION (juvenile male holotype, total length = 9.7 mm; Fig. 1 ).

Coloration. Translucent, immaculate pale whitish-yellow to beige, only with minor dark reddish brown to blackish details (cheliceral fingertips, pedipalp finger denticles, most macrosetae and trichobothria, leg articular condyles and tips of claws and apotele, and distal half of aculeus); carapace entirely lacking ocular pigment.

Pedipalps. Longer and slenderer than standard for the family. Trichobothrial pattern C, orthobothriotaxic. Femur long and slender, about as wide as deep, straight in dorsal and frontal views; dorsal, internal, ventral and external surfaces slightly convex to essentially straight; all carinae obsolete to absent; tegument smooth and glossy. Patella long and slender, about as wide as deep, straight in dorsal and frontal views; dorsal, internal, ventral and external surfaces slightly convex to essentially straight; all carinae obsolete to absent; tegument smooth and glossy, internal surface shagreened. Chela long and slender, only slightly deeper than wide; manus elongateoval and subcylindrical, distally narrower in dorsal view, moderately setose and oval in cross-section, with dorsobasal lobe round and very weak, all carinae obsolete to absent, tegument smooth and glossy; fingers long, slender, moderately curved and moderately setose, cutting edges with basal lobe/ notch combination absent but moderately scalloped (inner and outer accessory denticles very large and raised), principal denticles arranged into six irregular but mostly straight rows, each flanked by very few outer supernumerary denticles (inner supernumerary denticles entirely absent).

Carapace. Slightly longer than wide and heptagonal. Anterior margin moderately bilobed, with 3–4 pairs of dark macrosetae (long, thin and dark) plus several minor setae (thin and pale), frontal lobes broadly paraboloid; median notch widely U-shaped, deep. Tegument smooth and glossy, with many minor pale setae scattered all over, plus two pairs of dark macrosetae (one closely set pair on dorsosubmedian position, another widely spaced on lateromedian position). Carinae absent. Furrows: anterior median, lateral oculars, central median, posterior median, posterior marginal lateral centrals and posterior laterals wide and deep, irregularly fused altogether. Median ocular tubercle absent but indicated by the lateral ocular furrows; median and lateral eyes absent, entirely lacking lens and ocular pigment.

Genital operculum. Small and prominent. Halves not separated nor fused and roundly subtriangular in shape; tegument smooth and glossy. Genital papillae medium-sized, only slightly protruding and digitiform.

Pectines. Small (just reaching coxa-trochanter joint of leg IV), subrectangular and sparsely setose. Tooth count 6/6, teeth digitiform and slightly swollen, almost straight and basally separated; fulcra small, suboval and little bulky. Basal plate much wider than long; anterior margin widely and shallowly notched medially, posterior margin straight; tegument smooth.

Legs. Very long and slender for the family, with all carinae absent or indistinct; tegument smooth and glossy. Telotarsi with spiniform setal formula 3/3: 4/4: 5/5: 5/5. Claws moderately long (about one-third the length of its respective telotarsus), well curved.

Mesosoma. Tergitesalmostbare, anteriorandposteriormargins almost straight; I–VI acarinate, VII with four inconspicuous carinae (submedian and lateral pairs very short and composed only of 2–3 aligned traces of granules); tegument smooth and glossy. Sternites densely setose (setae long and rigid, larger and denser along posterior margin), posterior margin very shallowly concave to bilobed (III–VI) or essentially straight (VII); III–VI acarinate, spiracles small and almost round; VII with traces of four inconspicuous carinae on posterior margin (submedian and lateral pairs, both extremely short, as minute lumps on posterior margin); tegument smooth and glossy.

Metasoma. Size standard for the family, but markedly slender, subcylindrical and sparsely setose. All carinae obsolete to absent except for the ventral transverse carinae, which is irregularly arcuate and composed of minute vestigial granules; anal arc finely and irregularly denticulate; laterodistal lobes of V inconspicuous and blunt. Intercarinal tegument smooth and glossy. Dorsal furrow complete, wide and moderately deep.

Telson. Densely covered with very long, dark and pale macrosetae all over except dorsally. Vesicle oval-slender but bulbous; tegument smooth and glossy, with a transverse ventrobasal row of four traces of granules and the standard four longitudinal furrows (smooth and shallow); ventral median carina absent, subaculear tubercle medium-sized, digitiform, densely setose and with very few scattered vestiges of granules dorsally. Aculeus very short, slender, sharp and weakly curved (tip broken).

COMPARISON. This species is very easy to distinguish from all other described congeners by its fully troglomorphic habitus. It is known from a single juvenile only, but the following two diagnostic characters are reliable by being ontogenetically invariable (i.e., never change as the animal grows and finally matures): 1) carapace entirely lacking eyes (without any traces of lens and ocular pigment) and median ocular tubercle; 2) pedipalps, legs and metasoma conspicuously attenuate (remarkably longer and slenderer than in all other known species and their instars).

These characters are shared only by the second species described in the present paper. The distinction between them both is found below, in its Comparison section.

DISTRIBUTION ( Fig. 3 ). This species is known only from the type locality and by being a troglomorphic troglobite, it is most likely a local endemic from this cave. It is located about 7 km from the seashore in the low, limestone coastal plain of southeastern Hispaniola.

ECOLOGICAL NOTES. There is no information in any of the labels accompanying the type specimen but from its fully troglomorphic habitus and cave occurrence, it is a presumed troglobite. In October 2016, the first author made a short visit to this cave but was allowed only to make a fast and superficial search along the well-illuminated touristic passage and even UV detection was used, no specimens were detected. Nevertheless, two decayed pedipalp chelae of different specimens were found under small rocks, in the darkest ascending chamber connected by crevices and micro-passages to the ecologically preserved, deeper section of the cave where this species most likely lives ( Fig. 4b ). Another, more intensive search, conducted by the second author in August 2021, did not yield any finding of this elusive species.

Cueva de las Maravillas is a big cave that was formed mostly due to water-erosion by a subterranean river born in the Cordillera Oriental, which still flows today some 20 m below the cave floor; the cave itself has eight main chambers interconnected by seven galleries and is communicated to the exterior though three entrances (Ministerio de Medio Ambiente y Recursos Naturales, 2020).

In the general karstic area outside the cave, the vegetation is mesic, broadleaf semicaducifolious forest with various degrees of human alteration ( Fig. 4a ). During a previous diurnal search there the first author found another diplocentrid scorpion, Cazierius cicero (Armas & Marcano Fondeur, 1987) , together with the buthids Centruroides altagraciae Teruel, Armas & Kovařík, 2013 and Microtityus consuelo Armas & Marcano Fondeur, 1987 .

REMARKS. The two adult chelae available are both about 6.5 mm long and their general shape is slender (as expected for a troglomorphic troglobite), but not more than in the slenderer adults of Cazierius , i.e., the females of Cazierius garridoi Armas, 2004 . The adult size/chela length ratio in this genus (calculated herein from preserved specimens of all known species, deposited in the first author’s personal collection), ranges in absolute values from 3.40 in the most robust male of Cazierius parvus Armas, 1984 , to 5.23 in the female holotype of C. garridoi . Thus, by applying this ratio we extrapolate that the two adults of C. cayacoa sp. n. to which these chelae belonged (regardless their sex), measured not less than 22 mm and not more than 34 mm.

Figures

Figure 1. Cazierius cayacoa sp. n., juvenile male holotype, habitus: a) dorsal; b) ventral. Scale bar: 1 mm.

Figures 3–4. Figure 3. Updated geographical distribution of the genus Cazierius in Hispaniola: troglobitic species (stars) and epigeic species (circles). Records include the complete literature published on the genus, plus unpublished data of the first author. Figure 4. Habitat and microhabitat of the troglobitic species of Cazierius described in the present paper: a–b) C. cayacoa sp. n., surroundings of Cueva de las Maravillas (a) and interior of the cave (b); c–d) C. ciguayo sp. n., surroundings of Cueva de los Murciélagos (c) and interior of the cave (d).