A new species of Sarax Simon, 1892 from the Philippines (Arachnida: Amblypygi: Charinidae)

A new species of the genus Sarax Simon, 1892 is described from Panay Island, Philippines. Sarax curioi sp. n. is the second species of the genus from the country and can be distinguished from the other Philippine species (Sarax brachydactylus Simon, 1892) by the sclerotized granules of the pedipalp surface, the spines of the pedipalp distitibia, the number of denticles of the chelicerae claw and the shape of the denticles of the chelicerae basal segment. Sarax newbritainensis Rahmadi and Kojima, 2010 is newly recorded from New Ireland Island, Papua New Guinea.


INTRODUCTION
Amblypygi are flattened arachnids with raptorial pedipalps and extremely elongate antenniform first legs, being commonly known as whip spiders.This order has approximately 160 species among five families distributed globally (Rahmadi et al. 2011).In the Southeast Asia, the amblypygid fauna encompasses the families Charinidae (with the genera Catageus Thorell, 1889, Charinus Simon, 1892 and Sarax Simon, 1892), Charontidae (with the genera Charon Karsch, 1879 and Stygophrynus Kraepling, 1895), Phrynidae (with the genus Phrynus Lamarck, 1801), and Phrynichidae (with the genus Phrynichus Karsch, 1879) (Harvey 2002(Harvey , 2003)).In this region, Sarax is the most diverse genus being composed by 12 species distributed on the continental and insular Southeast Asia (from Laos to Indonesia) (Harvey 2003, Rahmadi et al. 2010).In the Philippines, just Sarax brachydactylus Simon, 1892 is recorded from the Luzon Island, Palawan Island and Cebu (Fig. 14).Although very similar to Charinus, mainly regarding the pedipalpalp tibia spination, Sarax can be distinguished by the presence of a ventral sac cover (Weygoldt 2000, Rahmadi andKojima 2010).After studying a specimen sent by Dr. Eberhard Curio and examining some additional specimens, including the type series of Sarax brachydactylus, we recognized a new species from Malumpati, Antique Province, Panay Island, Philippines, which is described and illustrated here.To better visualize and compare both Philippine species of Sarax, pictures of S. brachydactylus are also given

MATERIALS AND METHODS
The specimen was deposited in the National Museum of the Philippines, Manila.The observations, measurements and drawings were made using a stereomicroscope camera lucida (Wild).For measurements and nomenclature, we followed the proposals of Quintero (1981) in general.The article called tarsus by Quintero is here divided into distitarsus and tarsal claw (pretarsus) as the two articles are not fused in Charinidae.The pictures were taken with a Sony Cybershot DSC-V1 attached to the stereomicroscope.The measurements of pedipalp articles were taken between the external condiles of each segment, in order to establish fixed points and proper length measurements (illustration in Baptista and Giupponi 2002).The measurement accuracy is indicated in the legend of each figure.

Taxonomy
1-2): flattened, wider than long (ratio a little less than 3/4); prominent eyes, median eye tubercle dark-brown, without apical setae, triangular in shape; median eyes facing antero-laterally; lateral eyes close to the lateral margin of the carapace, yellowish pale in color; from the median eye tubercle starts a thin median furrow that reaches around the posterior area of the pair of lateral humps situated behind the lateral eye spots.Anterior margin with 6 small setae.Corners of the anterior margin extending downwards abruptly in front of the lateral eyes.Many tiny punctuations more abundant in the frontal area.Punctuations arranged in lines and spots, irradiating from the fovea and interspersed with smooth areas.3 pairs of deep furrows and a deep, triangular fovea.The first pair of furrows placed just behind the lateral boss and not reaching the middle line.3 lateral pairs of depressions (the first one placed over the first pair of furrows).Frontal process well developed, much longer than larger, with blunt, thickened apex.Sternum (Fig. 3): tri-segmented, all segments sclerotized and convex.Tritosternum with a round basis and projected anteriorly in a small blunt tubercle, with 2 apical, 3 medial and 2 basal setae, and some small setulae along the projection.Middle piece rounded, convex, with 2 setae and a few setulae.The third piece is also rounded and convex, but smaller and with smaller setae than the second piece.The second and third pieces are less sclerotized than the tristosternum.Sternites separated from each other by the diameter of the third piece.Abdomen (Fig. 1): oblong, with almost indistinguishable punctuations, thinner than in the carapace.Chelicera: Cheliceral furrow (Fig. 7) with 4 internal teeth, the distal one bifid, the first cusp bigger than the second one.The fourth tooth twice as long as the others and much stouter.Teeth length (from tip to basis) IV>Ia>Ib=II>III.Claw without denticles.Color pattern (in alcohol): Chelicerae, pedipalps and carapace yellowish.Legs light colored.Abdomen pale yellow.Genitalia: Unknown.The gonopod of the specimen was destructed before it could be analyzed.

Natural history
The specimen herein described was collected on the forest floor of Malumpati.The female was carrying nine eggs.

DISCUSSION
The genus Sarax has currently 17 species and two subspecies, distributed from Greece to Papua New Guinea.Among all these species, Sarax curioi sp.n. is the only one with geminated spines on the pedipalp distitarsus, without denticles on the cheliceral claw and with 21 pseudo-articles on tibia I.
The amblypygid fauna in the Philippines is poorly known.With this new species, the number of species raises to three: Charon grayi Gervais, 1842, Sarax brachydactylus and S. curioi sp.n..This is the first time that an amblipigid is recorded from the Panay Island, which shows that the Philippines is still a sub-sampled area.This is evidenced by the absence of species of the genus Sarax (the most diverse genus in the Southeast Asia) in three of the seven biggest islands that constitute the country (Mindanao, Mindoro and Samar) (Fig. 14).
Sarax curioi sp.n. can be easily distinguished from the other Philippine species.The corners of the anterior margin of the carapace in S. curioi sp.n extend downwards abruptly in front of the lateral eyes (Fig. 2), which is different from Sarax brachydactylus, that has the lateral limits of the anterior margin of the carapace continued with the rest of the carapace edge (Fig. 8).The new species has the pedipalp with a strong granulation mainly on the femur and tibia, both on dorsal and ventral  and 5).The granules are visibly more sclerotized and have a darker coloration when compared with S. brachydactylus (Figs. 10 and 11).Also, the shape of the basitibia of the pedipalp is different between the species; the anterior portion of the basitibia (i.e. between the distal spine and the articulation with the distitibia) in Sarax curioi sp.n. has a higher inclination (Fig. 6) when compared with S. brachydactylus (Fig. 12).Besides, the pedipalp distitibia of Sarax curioi sp.n. has a pair of geminated spines both sharing the same base (Fig. 6), while the distitibia spines of S. brachydactylus are clearly separated as the pattern conformation observed among the Charinidae species (Fig. 12).
Several differences can be observed concerning the chelicerae of both species.S. curioi sp.n. has the cheliceral claw without denticles (Fig. 7), whereas S. brachydactylus has four denticles (Fig. 13).The bifid denticles of the basal segment of the chelicerae in S. curioi sp.n. are curved upwards, while in S. brachydactylus the bifid denticles point forwards; the basal denticle (the largest) is straight in S. curioi sp.n. but is curved in S. brachydctylus; the denticle that follows the basal one (the largest) is much shorter than the others in S. curioi sp.n., while it is subequal in S. brachydactylus (but always smaller than the proximal one).
New record of Asian Sarax.Sarax newbritainensis Rahmadi and Kojima, 2010 is recorded from New Ireland Island, Papua New Guinea.This is the first record of the species elsewhere of the type locality, in New Britain.Rahmadi and Kojima 2010 say that this species has on its tibia and tarsus I 23 and 41 articles, respectively, but in the specimen here analyzed 29 and 41 articles were reported, respectively.
List of the Sarax species and subspecies with its known area of occurrence:
. Moreover, a new record of Sarax newbritainensis Rahmadi and Kojima, 2010 is made.