Sarax timorensis, Miranda, Gustavo Silva de & Reboleira, Ana Sofia P. S., 2019

Miranda, Gustavo Silva de & Reboleira, Ana Sofia P. S., 2019, Amblypygids of Timor-Leste: first records of the order from the country with the description of a remarkable new species of Sarax (Arachnida, Amblypygi, Charinidae), ZooKeys 820, pp. 1-12 : 1

Sarax timorensis sp. n. Figs 1, 2, 3

Type material.

Holotype: Timor-Leste: Lautém district, Puropoko Cave, 8.543832N 127.066215E, 6-12.ix.2016, A.S.P.S. Reboleira leg. (male, NHMD). Female unknown.

Diagnosis.

Sarax timorensis sp. n. can be recognized by the large size (body total length 12.82 mm), presence of only two pairs of lateral eyes, eight frontal setae, cheliceral claw with six teeth, two spines on dorsal pedipalp tarsus, male gonopod with sclerotization on the base of fistula, dorsal lobe and lateral lobe II, basitibia IV with four pseudoarticles and distitibia IV with six trichobothria on the frontal and caudal series. The new species can be distinguished from its congeners by the presence of only two pairs of lateral eyes, a unique character state known only from a few fossil species ( Kronocharon longicalcaris Wunderlich, 2015 and Paracharonopsis cambayensis Engel & Grimaldi, 2014). Sarax timorensis sp. n. differs from the fossil species by the size (new species much larger) and the number of spines on the pedipalp. Female unknown.

Description of holotype male.

(All variation are from right-left asymmetry): Carapace (Figs 1A, B; 2 A–C) with small granules scattered between the lateral eyes and among the sulcs. Median eyes and tubercle weakly developed (Fig. 1B); one pair of setae on the median tubercle; two pairs of lateral eyes (Fig. 2B, C) weakly developed, pale colored, with one setae lateral to the eyes; lateral eyes close to the border of the carapace; presence of a curved crest between lateral eyes and the border of the carapace; eight frontal setae; frontal process well developed, triangular, not seen from above. Tritosternum (Fig. 1C) projected anteriorly with the typical Charinidae setation; tritosternum long, surpassing the base of the pedipalp coxae; other sternal platelets narrow and projected, with a pair of setae on the top of the plaque and some smaller ones in the base; pentasternum with four setae close to the membranous region and two setae distally.

Chelicera (Figs 3 D–G) with a broad and short projection on the ectal side, opposite to the bifid tooth, on the basal segment; ectal side of cheliceral claw (Fig. 3F) with row of setae until the middle of the claw; cheliceral claw with six teeth; mesal side of basal segment proximally with several setae in more than two rows; bifid tooth of basal segment with four teeth in the row with upper cusp larger than lower.

Abdomen with ventral sacs cover well developed. Male genital operculum (Figs 3 A–C) with short setae in the border of the genital plaque; longer setae scattered over the setae of the genital operculum; inner border of the fistula well sclerotized (Figs 3A, B); base of LoL 2 sclerotized; LoL 2 fimbriated; PI not surpassing the border of the LaM.

Pedipalp coxae without setae inside the round carena and with 3-4 setae in its border. Pedipalp trochanter with ventral apophysis pointing forward (Fig. 1D, E), bearing more than 20 strong setae; one spine below the apophysis half the size of the projection of the apophysis and one spine in the middle of the trochanter, in the same row of the long setae. Pedipalp femur (Fig. 1D, E) with four dorsal and with 3-4 ventral spines in the main series; femur dorsal with three prominent setiferous tubercles between the first spine and the proximal margin; femur dorsal with one smaller spine between spines 1-2 and 2-3; femur ventral with one long spine between spine 1 and proximal margin of the segment, two thirds spine 1; femur ventral with 2-3 spines between spines 1-2 and one spine between spines 2-3. Pedipalp patella (Fig. 1D, E) dorsal with 4-5 spines in the main series; one prominent spines distal to spine I; patella ventral with 3-4 spines decreasing in size from distal to proximal; three small setiferous tubercle between spine I and distal border. Pedipalp tibia (Fig. 1D, E) dorsal with two long spines, the distal longer than the proximal; tibia ventral with one distal spine and 5-7 long setae between spine and distal margin. Pedipalp tarsus (Fig. 1D, E; 2 D, E) with two dorsal spines in the right palp and one in the left palp; the two spines are short, subequal; cleaning organ with 37 setae in the ventral row. Tibia I with 23; tarsus I with> 26 articles (both legs incomplete; this number refers to the leg with most of the articles); first tarsal article the same size as the following article. Basitibia IV divided in four pseudo-articles, with a sclerotized, denticulated border in the apex of the articles; bt in the distal third of the pseudo-article; distitibia IV with trichobothria bc closer to sbf than to bf, and sc and sf with six trichobothria each.

Measurements (in mm): Carapace: length 4.96, width 6.64. Body total length: 12.82. Pedipalp (right-left): femur 7.76-8.0, patella 7.52-7.62, tibia 2.36-2.60, tarsus 1.88-1.94, tarsal claw 1.16-1.28. Leg I femur 20.8. Leg IV: femur 11.7, basitibia IV–I 9.0, basitibia IV–II 2.6, basitibia IV-III 2.6, basitibia IV–IV 2.6, distitibia 5.25, basitarsus 2.56, other tarsal articles 1.48.

Habitat.

The new species was found in a cave on the border of the Ira Lalaro Lake, a huge closed karst depression in the Eastern part of the Timor Island ( Freire et al. 2017; O’Connor et al. 2017). The atmospheric temperature in the cave is 32 °C. The cave has a stream with a high density of leeches in its substrate and harbors a large colony of Chiroptera . Some snakes were also observed hunting the bats in its narrow galleries. The high content in bat guano gives rise to high densities of cockroaches which are very active along the cave.