Dysdera zonsteini Dimitrov 2021, new species
Creators: name: Dimitrov, Dragomir
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Dysderidae
Dysdera
Dysdera zonsteini

description: Dysdera zonsteini new species
Figs 1–13
Type material. Holotype. ³. Turkmenistan, South-Western Kopet Dagh, near Kara-Kala Town, GPS: 38°28’N, 56°15’E, alt. 350–450 m, 21.04.1985, Sergei Zonstein leg. (MNHN, AR 5862). Paratype. 1♀, with same data as for holotype (MNHN, AR 5862).
Etymology. Named after the well-known arachnologist Sergei Zonstein, who collected the type specimens.
Diagnosis. Both male and female of Dysdera zonsteini n. sp. are morphologically close to Dysdera kronebergi Dunin, 1992. The two species can be separated by the following diagnostic characters: (1) the smaller size of D. zonsteini n. sp. [carapace length 1.65 vs. 2.45 in D. kronebergi]. Male of the new species differs also by (2) the strong process (PE) of the embolic division (Figs 7–9, 14) that is not seen in D. zonsteini (Dunin 1992, figs. 4–5) and (3) the overall shape of the tegulum and the embolic division of the bulb (Figs 7–10, 14–15). Female differs by (4) the thinner and straight transversal bar (Figs 12–13, 16–17) vs. more massive and with curved edges in D. kronebergi (Dunin 1992a, fig 6) and by (5) the more oval shape of the dorsal arc of the anterior diverticulum. The spermathecae of the two species are almost identical, but (6) in D. kronebergi it is wider than the dorsal arc of anterior diverticulum (Dunin 1992a, fig 6), while in D. zonsteini n. sp. it is narrower and its lateral wings do not exceed the width of the dorsal arc in its base (Figs 12–13, 16–17).
Description. Male. (Figs 1–2, 5, 7–11, 14–15). Measurements. Total length 4.05; carapace length 1.65, width 1.18; sternum length 1.05, width 0.75; cheliceral length 0.72, width 0.25; clypeus height 0.05; labium length 0.40; gnathocoxa length 0.58; abdomen length 1.95, width 0.85; Eye diameters: AE—0.17, PE—0.14. Leg measurements. I—5.53 (0.92, 1.33, 0.77, 0.97, 1.04, 0.50); II—4.86 (0.83, 1.26, 0.43, 0.93, 0.94, 0.47); III—3.61 (0.65, 0.97, 0.43, 0.55, 0.65, 0.36); IV—4.66 (0.72, 1.13, 0.58, 0.86, 0.97, 0.40). Leg spination: coxae, trochanters and patellae spineless. Legs I and II have only one distal prolateral femoral spine, legs III and IV with well-armed femur and metatarsus. I—1pl, 0, 0; II—1pl, 0, 0; III—1d, 5pl 5rl, 5pl 2rl; IV—4d, 6pl 6rl, 6pl 5rl. Colouration very pale. Carapace, chelicerae and sternum light orange. Sternum a little lighter than the carapace. Abdomen and legs white. Other somatic characters. Body long and slim. Chelicerae dorsally covered with small tubercles. The distance between the AE equal to their diameter. Posterior eye-row very slightly procurved, almost straight. PE touching to each other. PLE touching to AE. Chelicerae with 3 teeth of approximately the same size, arranged in one row. The proximal one positioned near the base of the cheliceral groove, the medial one is close to it and the distal one is approximately at the middle of the groove (Fig. 5). Labium pyramidal, notched distally. Tarsi with 2 claws and claw tuffs. Anterior border of sternum wider than the labium.
Palp. (Figs 7–11, 14–15). Cymbium length 0.45; Male copulatory bulb length 0.63. Tegulum oval, almost rounded from retrolateral view. Embolic division wide, bent in the middle, unevenly sclerotized, with massive process starting from its base. Embolus opens at the distal end (Figs. 10, 15). Crest positioned diagonally in the distal part of the embolic division (Fig. 15). Lateral sheet weakly sclerotized, almost transparent. Posterior apophysis short and bent perpendicularly to the embolic division, detached from the tegulum and surrounded by the distal haematodocha.
Female. (Figs 3–4, 6, 12–13, 16–17). Measurements. Total length (including the chelicerae) 4.68; carapace length 1.80, width 1.26; sternum length 1.12, width 0.80; cheliceral length 0.72, width 0.35; clypeus height 0.05; labium length 0.41; gnathocoxa length 0.65; abdomen length 2.88, width 1.44; Eye diameters: AE—0.17, PE— 0.14. Leg measurements. I—5.41 (0.94, 1.25, 0.80, 1.04, 0.98, 0.40); II—4.92 (0.86, 1.12, 0.79, 0.90, 0.90, 0.35); III—3.34 (0.50, 0.76, 0.47, 0.54, 0.77, 0.30); IV—4.64 (0.76, 1.04, 0.58, 0.92, 1.04, 0.30). Leg spination as in male. Coloration very pale. Carapace, chelicerae and sternum light orange. Sternum a little lighter than the carapace. Abdomen and legs white. Anterior border of sternum as wide as the base of labium. Other somatic characters as in male (Figs. 3–4, 6).
Vulva. (Figs 12–13, 16–17). Transversal bar width 0.38. Spermatheca small, with mushroom-like anterior part and deeply notched base. Dorsal arc of anterior diverticulum shaped as an irregular trapeze, wider than the spermatheca, weakly sclerotized, with almost transparent edges. Transversal bar comparatively straight. Posterior diverticulum wide, membranous.
Distribution. Known only from the type locality in southwestern Turkmenistan.
Discussion. The new species’ morphologically closest congener D. kronebergi was diagnosed as being close to the Dysdera gigas species-group (Dunin 1992a: 137), referring to Deeleman-Reinhold & Deeleman (1988). However, there is no D. gigas -group defined in the cited paper. Instead, D. gigas along with another three similar species are listed under the Dysdera asiatica -group (Deeleman-Reinhold & Deeleman 1988: 210). The authors explicitly mention that the lateral sheet is missing in these species whereas in D. zonsteini n. sp. it exists. All the species related to D. gigas are known from Greece and the Greek islands and their relationship with D. kronebergi suggested by Dunin is doubtful, since neither the genital morphology nor their distribution ranges support it.
Some important morphological traits of the new species correspond well with the diagnose of the D. asiatica -group (sensu Deeleman-Reinhold & Deeleman 1988): 1. Chelicerae are shorter than half of the length of the carapace; 2. The embolic division is longer than the tegulum; 3. The presence of crest and lateral sheet on the embolic division of the male palp; 4. The arched spermatheca of the vulva.
However, the diagnosis of the group itself (sensu Deeleman-Reinhold & Deeleman 1988) has one serious disadvantage: it is named after a species known only by male sex. Thus, all the other members of the group are linked to Dysdera asiatica based only on the males. Apart from that, as already stated by Deeleman-Reinhold & Deeleman (1988: 210), the group is very rich in species and in Central Asia is neither homogenous nor can be clearly separated from the D. aculeata -group. The group warrants a thorough new revision. Here, I provisionally place D. zonsteini n. sp. in D. asiatica species-group. Most of the other species, known from Turkmenistan belong to the D. aculeata -group according to the same classification.
Although the data about the distribution of D. zonsteini n. sp. are insufficient to identify with certainty its zoogeographical status, its occurrence in the southern part of the country implies that it could be an Irano-Turanian species.
description: Published as part of Dimitrov, Dragomir, 2021, Description of Dysdera zonsteini n. sp. (Arachnida: Araneae: Dysderidae) from Turkmenistan, pp. 588-594 in Zootaxa 4938 (5) on pages 589-593, DOI: 10.11646/zootaxa.4938.5.6, http://zenodo.org/record/4575108