Oaphantes prometheus, Paquin & Dupérré & Buckle & Ubick, 2020

Paquin, P., Dupérré, N., Buckle, D. J. & Ubick, D., 2020, Caves as a key habitat for rare and endemic species of the west coast of North America: a taxonomic revision of the spider genus Oaphantes (Araneae Linyphiidae), Zootaxa 4819 (2), pp. 349-363 : 357-359

Oaphantes prometheus new species

( Figs 17–26 )

Oaphantes sp.1: Paquin et al. 2009a: 51–53, Elliott et al., 2017: 181.

Type material.— HOLOTYPE: USA: California: Tulare Co., Sequoia National Park, Paradise Cave , 30.iv.2004, 1814m, on cave wall deep zone, hand collecting, 1♂, P. Paquin, D. Ubick, J. Krejca, P. Sprouse (Deposited at CAS 9078643).

PARATYPES: USA: California: Tulare Co., Sequoia National Park, Paradise Cave , 1814m, 22.vii.2003, hand collecting, 2♀ 3 juveniles, J. Krejca, V. Loftin, S. Fryer, C. Walck (CAS 9078636, 9078637, 9078638, 9078639, 9078640); same, 30.iv.2004, on cave wall deep zone, hand collecting, 1♀, P. Paquin, D. Ubick, J. Krejca, P. Sprouse (CAS 9078635); same, 2♂ 3♀, D. Ubick, P. Paquin ( CDU) .

Diagnosis.— O. prometheus n. sp. can be distinguished from the other species by the absence of eyes ( Figs 17, 18 ). Males of O. prometheus n. sp. most resemble those of O. pallidulus but differ by their smaller size, the moderately elevated carapace in the cephalic region and the absence of eyes ( Fig. 17 ). The male palps differ from those of other species by the paracymbium (P) bearing a straight longitudinal keel ( Fig. 19 ) and an embolus (E) harbouring a blunt spike on its basal half ( Fig. 20 ). Females are diagnosed by their smaller size, the absence of eyes ( Fig. 18 ) and by the heart-shaped anterior epigynal margin and long, straight scape (SC), ∼ 2\5 length of abdomen ( Figs 22, 24 ).

Description.— Male (n=1): Total length: 2.11; carapace length: 1.15; carapace width: 0.87; carapace, smooth, shiny, light yellow orange (130M), moderately elevated in cephalic region, bearing 6 erect setae along midline. Eyes absent ( Fig. 17 ). Sternum light yellow orange (130M). Chelicerae light yellow orange (130M), promargin not carinated, with 3 teeth and a small mastidion ( Fig. 17 ), retromargin with 4 denticles, presence of setae-tipped tubercles on cheliceral surface. Cheliceral stridulatory organ visible with ∼ 22 striae. Endites light yellow orange (FFD700), with a single setose tubercle. Abdomen off-white (7500M), sub-cylindrical, pointed apically, covered with long semi-erected setae; ventral surface of abdomen bearing oval striated epigastric plates. Legs long and slen-der, light yellow orange (130M), formula 1-4-2-3; tibia I–IV with 2 long dorsal macrosetae; metatarsus I with dorsal trichobothrium, Tm I 0.38, Tm IV absent; coxae IV with stridulatory pick. Palpal femur with stridulatory pick. Male palp with complex paracymbium (P) bearing a longitudinal straight keel, a proximal pocket (PPO) and proximal protuberance bearing three long setae, apical part with 1 short such seta ( Fig. 19 ); embolus (E) long, bearing a blunt spike on its basal half, curving and extending beyond the cymbium ( Figs 20, 21 ); embolic membrane (EM) long ( Fig. 20, 21 ); terminal apophysis (TA) basally well-sclerified with embossed surface, apical end membranous and acuminate ( Fig. 20, 21 ); lamella characteristica (LC) large and twisted ( Fig. 20, 21 ); 2 teeth distal suprategular apophysis (SA) ( Figs 19, 21 ); retrolateral tibial apophysis (RTA) present ( Fig. 19 ).

Female (n=1): Total length: 2.23; carapace length: 0.93; carapace width: 0.78; carapace colouration as in male, not raised in cephalic region, bearing 5 erect setae along midline; eyes absent ( Fig. 18 ). Colouration of sternum and chelicerae as in male, promargin of chelicerae with 4 teeth, retromargin with 4 large denticles, presence of setaetipped tubercles on cheliceral surface. Cheliceral stridulatory organ visible with ∼ 15 striae. Endite colouration as in male, without setose tubercle. Abdomen colouration as in male, sub-cylindrical, pointed apically, covered with long semi-erect setae; ventral surface of abdomen bearing oval striated epigastric plates. Legs long and slender, light yellow orange (FFD700), formula 1-4-2-3; tibia I–IV with 2 long dorsal macrosetae; metatarsus I with dorsal trichobothrium, Tm I 0.43, Tm IV absent; coxae IV with stridulatory pick. Palpal femur with stridulatory pick. Epigynum defined by broad, heart-shaped anterior margin of scape, gradually narrowing in a long, straight scape (S), ∼ 2\5 of the abdomen length ( Figs 22, 24 ); spermathecae (S) oval, secondary spermathecae (SS) elongate, slightly curved and directed posteriorly ( Fig. 23 ); copulatory openings (CO) located on the underside of the scape near the apex, associated with terminal pockets (TP) ( Fig. 23 ); copulatory ducts (CD) long ( Fig. 23 ); fertilization ducts (FD) short and recurved ( Fig. 23 ).

Distribution.— Only known from Paradise Cave in Sequoia National Park, Tulare Co., California.

Habitat. —Deep inside cave, in webs along walls.

Etymology.— The epithet refers to the Greek Titan Prometheus who was punished for stealing fire from heaven and giving it to mankind. The type locality is Paradise Cave (= heaven) from which the species was collected.

Remarks.— Cave obligate, troglobite.

Figures

FIGURES 17–24. Oaphantes prometheus 17, face of male, frontal view (arrow points to mastidion); 18, face of female, frontal view; 19, male palp, retrolateral view (arrow points to paracymbial keel); 20, male palp, prolateral view (arrow points to embolus blunt spike); 21, embolic division of male palp, prolateral view; 22, epigynum, ventral view; 23, internal genitalia, dorsal view, 24, epigynum of female, lateral view. Scale bars for figures 17–18, 22–24 = 0.5mm; figures 19–21 = 0.1 mm.

FIGURE 25. Distribution map of Oaphantes pallidulus (Banks 1904), O. cryophilus n. sp. and O. prometheus n. sp.

FIGURE 26. Male Oaphantes prometheus in Paradise Cave. Photograph by J. Krejca.