Ischnothyreus hanae, Tong & Li, 2008

Tong, Yanfeng & Li, Shuqiang, 2008, The Oonopid Spiders (Araneae: Oonopidae) From Hainan Island, China, Raffles Bulletin of Zoology 56 (1), pp. 55-66 : 59-60

Ischnothyreus hanae , new species

( Fig. 3A–D )

Holotype. – Female ( IZCAS), Bawangling National Natural Reserve (19 ° 04'N, 109 ° 08'E), Changjiang County, Hainan Island, China, coll. Y. Song, X. Han, G. Deng and Y. Tong, 22 Mar.2005.

Paratypes. – 1 female ( IZCAS), same data as holotype .

Diagnosis. – The female of this new species (male unknown) is similar to the widely distributed species I. peltifer (Simon, 1891) ( Saaristo, 2001) , but can be distinguished by the distinctly longer abdominal dorsal scutum, the shape of ventral postepigastric scutum and the goblet like atrium of female.

Description. – Female. Body length 1.18–1.29; carapace 0.61–0.62 length, 0.50–0.52 width; abdomen 0.60–0.69 length, 0.32–0.35 width. Carapace and dorsal scutum brown; chelicerae, sternum, legs and ventral scuta yellow. Carapace with three rows of short hairs dorsally. Eyes six in two rows, quite compactly arranged; eyes sizes relatively smaller than those of I. falcatus , new species; ALE about one-fourth of their diameter apart; posterior eyes in a slightly procurved row, touching each other. Labium wider than long, tip of endites truncated. Leg I: femur with 2 prolateral spines, patella spineless, tibia with 4 pairs, metatarsus with 2 pairs of very long ventral spines. Leg II is similar to leg I except femur with only one prolateral spine. Legs III and IV spineless. Measurements of legs: I 1.47 (0.43, 0.21, 0.37, 0.29, 0.17); II 1.46 (0.40, 0.22, 0.36, 0.30, 0.18); III 1.22 (0.36, 0.15, 0.24, 0.28, 0.19); IV 1.78 (0.51, 0.25, 0.39, 0.39, 0.24). Leg formula: 4> 1 = 2> 3. Dorsal scutum long oval-shaped, about four-fifths to five-sixths abdominal length. Postepigastric scutum elongated triangular. A strongly winding tube visible through cuticle, originated from near the middle of epigastric sulcus and running posteriorly into the goblet like atrium.

Male. Unknown.

Discussion. – The species I. falcatus , new species and I. hanae , new species (male unknown) are collected in the same locality, but the females of these two species can be easily distinguished by the length of abdominal scutum and the shape of atrium. Based on the similarity of the shorter abdominal scutum (most species of Ischnothyreus with longer abdominal dorsal scutum in male than that in female ( Chickering, 1968), but the female of I. hanae , new species has a distinctly longer abdominal dorsal scutum than the male of I. falcatus , new species. This suggests that they might not be the same species), the steeper lateral view of carapace, the larger sizes of eyes, and the body colour, it will be able to help match the male and female.

Etymology. – This species is named after the collector Mrs. Xu Han.

Figures

Fig. 3. Ischnothyreus hanae, new species: A, carapace of female, lateral view; B, female, dorsal view; C, ventral scutum of female, ventral view; D, genital area of female, dorsal view. Scales: A, B = 0.2 mm, C = 0.05 mm, D = 0.025 mm.