Sarax cavernicola, Rahmadi, Cahyo, Harvey, Mark S. & Kojima, Jun-Ichi, 2010

Rahmadi, Cahyo, Harvey, Mark S. & Kojima, Jun-Ichi, 2010, Whip spiders of the genus Sarax Simon 1892 (Amblypygi: Charinidae) from Borneo Island, Zootaxa 2612, pp. 1-21 : 3-6

Sarax cavernicola sp. nov.

( Figs. 1 – 7 , 33 – 34 )

Material examined: Female holotype ( MZB.Ambl.145), INDONESIA: East Kalimantan: Kutai Timur Regency, Sangkulirang District, Pengadan Village, Gua Ambulabung (Gua Baai ) (KAL-110), GPS coordinates 1°9'11.00"N, 117°33'59.91"E, 16 August 2004, L. Deharveng. Paratypes: 2 females ( MZB.Ambl.146, MNHN-Am.0 8), 1 male ( MZB.Ambl.147), same data as holotype; 2 females ( MZB.Ambl.072 – 073), INDONESIA: East Kalimantan: Kutai Timur Regency, Kelai District, Marang, Gua Sungai, 22 August 2004, Y.R. Suhardjono; 2 females ( MZB.Ambl.091-092), INDONESIA: East Kalimantan: Kutai Timur Regency, Kelai District, Marang, Gua Sungai, GPS coordinates 1°05'38.78"N, 117°17'45.39"E, 23 August 2004, C. Rahmadi.

Diagnosis: Sarax cavernicola differs from other Bornean species by the rather large body (adult body length about 6.2 – 16.2 mm). Body yellowish-brown in color. Anterior margin of carapace broadly rounded, eyes slightly reduced in size. Pedipalpal femur with many spines both on antero-dorsal and antero-ventral margins; pedipalpal patella on antero-dorsal margin with three spines about equal in length; pedipalpal tibia on antero-dorsal margin with two spines (proximal spine less than half of distal one length) and on anteroventral margin with three spines decreasing in size from distal to proximal to major spine proximally; pedipalpal tarsus with three spines: proximal spine the shortest and the distal one the longest (medial spine close to the proximal one). Tibia of leg IV with 19 trichobothria: bc very close to sbf, bt close to proximal margin of fourth basitibial segment of leg IV.

Description: Female: Color in alcohol: Carapace yellowish-brown, centrally with brown marks; pedipalp yellowish-brown except for reddish-brown spines and tarsus. Legs II – IV yellowish-brown to light yellow, except patella dark brown. Abdomen yellow with a pair of spots on each tergite.

Carapace ( Fig. 1 ): Width about 1.3 – 1.5 times its length; surface finely granulate, without setiferous tubercles, with several short setae in frontal area. Flange wide and bent upwards. Anterior margin of carapace slightly rounded, with 6 frontal setae. Median sulcus deep in posterior one-third of the carapace; a line sulcus running from posterior of median eyes to central sulcus, two paired lateral sulci present running laterally, a pair of sulci on posterior of lateral eyes. Eyes small, median eye tubercle brown, without apical setae, reduced in size, triangular in shape; median eyes facing antero-laterally; lateral eyes close to lateral margin of carapace, reduced in size, yellowish pale in color; frontal process not visible from above in holotype, and visible in paratypes.

Chelicera ( Fig. 2 ): Dorsal surface smooth, without frontal setae and with several fine setae. Basal segment with 4 teeth: lower-most tooth largest, upper-most tooth bicuspid, with upper cusp larger than lower cusp; inner surface with several setae arranged in vertical row; outer surface with one small tooth opposite of bicuspid tooth, ventrally with several setae near proximal margin. Movable article with 6 teeth; second tooth the largest and subsequent teeth decreasing in size distally.

Sternum ( Fig. 3 ): First sternite (= tritosternum) elongate, with paired apical setae and laterally many setae shorter than apical setae. Second and third sternites rounded and slightly elongate, respectively with 8 and 6 setae in addition to paired apical setae. Fourth sternite (= metasternum) with 3 setae.

Pedipalp ( Figs. 4 – 5 ): Strong and slender. Trochanter with 10 setiferous tubercles and several setae along antero-dorsal margin, 1 spine medially and 7 setiferous tubercles on antero-ventral margin; ventro-anterior apophysis equipped with several setiferous tubercles present on distal margin of trochanter. Femur: anterodorsal margin with 6 major spines (length F1>F3>F5>F2>F4), several setiferous tubercles and small tubercles; antero-ventral margin with 7 major spines (length FII>FV>FI>FVIII>FIII>FIV>FVI>FVII), several minor spines and small tubercles. Patella: antero-dorsal margin with 3 major spines (P1, P2, P3) about equal in size, several minor spines, several setiferous tubercles and small tubercles, the three major spines located on more than half of pedipalpal patella length distally, 1 minor spine present between P1 and distal margin of patella, the length of minor spine less than half of P1 length, 1 minor spine present between P3 and proximal margin; antero-ventral margin with 4 major spines (length PI>PIII>PII>PIV), several setiferous tubercles and small tubercles, 2 minor spines between PIII-PIV and 3 minor spines between PIV and proximal margin. Tibia with several setiferous tubercles, outer surface roughened and several setae on inner surface; antero-dorsal margin with two major spines, proximal spine less than half as long as distal one; antero-ventral margin with 3 major spines ( Fig. 5 ), the distal-most spine longest, following spines decreasing in size proximally, other specimens (MZB.Ambl. 0 72 – 0 73, 0 91 – 092) have only one spine without 2 additional proximal spines. Tarsus completely divided (claw clearly demarcated by articulation), antero-dorsal margin with 3 spines: proximal and medial spines short, about equal in length and close to each other (space between them about basal diameter of medial spine), distal spine longer than proximal and medial spine, medial spine by about 3 basal diameter of medial spine, without basal row of seta on proximal end of cleaning organ; cleaning organ ventrally with about 30 modified hairs; apotele present.

Legs ( Fig. 6 ): Femora of legs I – IV with small tubercles and setiferous tubercles. Tibia and tarsus of leg I with 23 and 41 segments, respectively; tibiae of legs II and III two-segmented; basitibiae of leg IV foursegmented, fourth segment with 1 trichobothrium (value in parentheses: ratio of the distance from the trichobothrium to the proximal margin of the segment against the length of the segment), bt (0.45); distitibiae of legs II-IV each with 18 trichobothria, bf (0.05), sbf (0.23), bc (0.26), sf1 (0.60), sc1 (0.75), bt close to proximal margin of fourth basitibial segment, bc very close to sbf ( Fig. 6 ). Tarsi of legs II – IV four-segmented; first segment about as long as length of subsequent three segments combined; second segment with lightyellow transverse line; fourth segment without oblique slit; pulvilli present.

Genitalia ( Fig. 7 ): Covered ventrally with genital operculum slightly concave apically, paired with 2 tubes projecting medially.

Male ( Figs. 33 – 34 ): Similar to female, without distinct sexual dimorphism. Genitalia: Covered ventrally by genital operculum slightly concave on the posterior margin ( Fig. 34 ); paired apically-pointed small projections on medial lobes; 2 brown marks present on lateral lobes. In dorsal view, paired, anteriorly rounded with 2 light brown bands running from anterior to mid-length of genitalia, 2 small brown marks present medially ( Fig. 33 ).

Measurements (in mm): male (n=1) [female (n =3)]; values for segments of the appendages are their lengths. Body length (excluding chelicera) 8.64 [6.17 – 16.25]. Carapace: median length 3.20 [4.57 – 6.37]; width 4.17[6.30 – 8.29]; median eyes to anterior margin of carapace 0.08[0.11 – 0.15]; distance between lateral eyes 1.88[3.00 – 4.54]; lateral eye to anterior margin of carapace 0.37 [0.64 – 0.69]; lateral eye to lateral margin of carapace 0.14 [0.24 – 0.35]. Pedipalps: trochanter 1.08 [1.97 – 2.62]; femur 2.92[5.95 – 8.98]; patella 3.26 [6.15 – 9.08]; tibia 1.59 [2.81 – 3.82]; tarsus 1.87 [3.00 – 4.51]. Leg I: femur 17.08 [24.35 – 35.79]; patella 0.86[1.00 – 1.18]. Leg II: femur 8.25 [11.32 – 17.29], patella 1.11 [1.57 – 1.79]; basitibia 7.23[11.22 – 12.79]; distitibia 4.52 [6.92 – 10.40]; metatarsus + tarsus 2.95[4.08 – 5.42]. Leg III: femur 9.38 [13.16 – 18.72]; patella 1.18 [1.25 – 1.97]; basitibia 7.69 [11.67 – 19.32]; distitibia 5.18 [6.95 – 11.46]; metatarsus+ tarsus 3.59 [4.28 – 5.86]. Leg IV: femur 9.08 [12.92 – 18.28]; patella 1.18 [1.21 – 1.80]; basitibia 9.90 [13.14 – 23.28]; distitibia 4.81 [6.79 – 10.29]; metatarsus + tarsus 2.40 [4.21 – 6.13].

Etymology: The specific name is a Latin adjective meaning inhabiting caverns or caves.

Distribution: This species is only known from the Sangkulirang Karst, located in East Kalimantan ( Indonesia) ( Figs. 41, 42 ).

Natural history: The whip spiders of this species were collected in caves of Gua Ambulabung ( Baai ) and Gua Sungai (Marang). They were found to live with several cave arthropods to which most of them are new to science such as a giant cave cockroach Miroblatta baai Grandcolas & Deharveng 2007 , and the cave millipeds Plusioglyphiulus bedosae Golovatch et al. 2009 and P. pallidior Golovatch et al. 2009 . Lips (2002) reported a whip spider (identified as Acariens) from other caves in Marang together with a figure of a specimen (N o. 1074) from Lubang Tendoyan (Marang) which depicts a whip spider which has three equal-sized spines on the pedipalpal patella which we interpret as a specimen of S. cavernicola .

Remarks: Sarax cavernicola has three major spines about equal in size on the antero-dorsal margin of the pedipalpal patella, the pedipalpal tarsus divided into two parts, and pulvilli present on legs II – IV. These features somewhat resemble the genus Stygophrynus which is a member of the family Charontidae . The pedipalpal patella spination is similar to Stygophrynus moultoni from Klingkang Range in western Borneo (Kalimantan Barat, Indonesia) and differs from that species by the length of the proximal spine of the dorsal pedipalpal tibia about equal to the distal one (see Gravely 1915, fig. 9).

The following characters demonstrate that the new species here is not a member of the genus Stygophrynus : the pedipalpal tibia without at least three spinelets that increase in size from proximal to distal on the distal of major spine (see Kraepelin 1895, fig. 32; 1899, fig. 92), the absence of a basal row of setae on the proximal end of the cleaning organ on the pedipalpal tarsus (see Quintero 1986, Weygoldt 1996, 2000, 2002), the cheliceral dentition with the upper cusp larger than the lower cusp, and the tibial and tarsal segments of the antenniform legs with 23 and 41 segments, respectively. Most of these characters clearly conform to the family Charinidae . We tentatively place the new species within the genus Sarax to which it most closely resembles. However, we believe that in future a new genus may be established when the taxonomic position of the charinid genera is fully resolved.

Figures

FIGURES 1 – 7. Sarax cavernicola sp. nov., female holotype: 1. Carapace; 2. Left chelicera, external view; 3. Sternal area of opisthosoma, ventral view; 4. Left pedipalp, antero-dorsal view; 5. Left pedipalpal tarsus; 6. Arrangement of trichobothria on fourth basitibial segment and distibiae of left leg IV; 7. Female gonopods, dorsal view.

FIGURES 33 – 40. Male genitalia of Sarax species from Borneo: 33. S. cavernicola, dorsal view; 34. same, ventral view; 35. S. yayukae from West and Central Kalimantan, dorsal view; 36. same, ventral view; 37. S. sangkulirangensis new species, dorsal view; 38. ventral view; 39. S. mardua from Gua Mardua, East Kalimantan, dorsal view, 40. Ventral view. Scale bars: 0.5 mm.

FIGURES 41 – 42. Map showing the distribution of Sarax species: 41. The distribution in Southeast Asia, except for Sarax species from India and New Guinea. 42. A detailed map showing the distribution in the Sangkulirang Karst, East Kalimantan.