Atractides (Atractides) khuzestaniensis, Etemadi & Khanjani & Asadi, 2024

Etemadi, Isa, Khanjani, Mohammad & Asadi, Mahdieh, 2024, A new species of Atractides (Hydrachnidia: Hygrobatidae) from Iran, Persian Journal of Acarology 13 (1), pp. 13-20 : 14-17

Atractides (Atractides) khuzestaniensis sp. nov. ( Figs. 1–3 )

http://zoobank.org/ urn:lsid:zoobank.org:act:F25A94EF-A93F-4B70-B0F0-4C196D648FE6

Type material and deposition

Holotype female ( SBUK-AH201 f), two female and two male paratypes (SBUK-Hyg 11–14) dissected and slide mounted, Iran: Khuzestan Province, Behbahan river , 335 m asl., 30° 39′ 28′′ N, 50° 8′ 12′′ E, 15 September 2020, coll. Isa Etemadi. Holotype and all paratypes are deposited at SBUK .

Diagnosis

Dorsal integument striated; muscle attachments unsclerotized; pregenital sclerite in female with denticulate and slightly concave anterior margin, sword seta in P-4 serrate in the middle to the tip and close to distoventral hairs in both male and female. I-L-5 with S-1 and S-2 homomorphic and close. Ac small and roundish, in a curved line. Excretory pore unsclerotized. Vgl-1 not fused to Vgl-2.

Description

Female – Integument dorsally striated; mediocaudal margin of Cx-I slightly convex, apodemes of Cx-II in an obtuse angle; Vgl-1 not fused to Vgl-2 ( Fig. 1a ). Palp with convex ventrodistal margin; one of the three and one of the two dorsodistal setae of P-2 and P-3 plumose respectively. P-3 ventral margin straight; P-4 ventral margin divided by ventral hairs in sectors 1:1:1, sword seta in P-4 close to the distoventral hairs ( Fig. 2b ). I-L-5 long and slender, equally enlarged from the base to the insertion of S-1-2 setae, S-1-2 with a narrow setal interspace ( Fig. 2a ); S-1-2 homomorphic, proximally enlarged and pointed; I-L-6 slender with curved ventral margin ( Fig. 2a ). Excretory pore unsclerotized. Anterior margin of pregenital sclerite denticulate and slightly concave, acetabula small ( Fig. 1c ).

Measurements – (Holotype, following paratypes in parentheses) Idiosoma L 984 (955–972), W 787 (759–773), Coxal shield L 404 (378–393), Cx-III W 501 (475–489), Cx-I+II mL 94 (81–89), CxI+II lL 243 (217–232), Genital field L/W 173/209 (158/189–169/196), genital plate L 145(129–136), gonopore L 113 (103–109), pregenital sclerite W 95 (84–90), L Ac-1–3:17 (14–15), 21 (19–20), 20 (17–18). Palp total L 427 (395–410); dL/H, dL/H ratio P-1 37/47, 0.78 (30/41, 0.73–33/46, 0.71); P- 2 103/67, 1.53 (85/61, 1.39–98/60, 1.6); P-3 103/55, 1.87 (86/49, 1.75–97/50, 1.94); P-4 136/35, 3.88 (110/28, 3.92–106/25, 4.24); P-5 48/17, 2.82; (39/13, 3–45/16, 2.81) length ratio P-2/P-4 0.75 (0.77– 1). Gnathosoma vL 169 (123–152); chelicera total L 297 (253–263), L basal segment 208 (182–198), L claw 89 (65–78), L ratio basal segment/claw 2.33 (2.8–2.53).

Legs– I-L-5 dL 299 (225–268), vL 153 (123–136), dL/vL ratio 1.95 (1.82–1.97), maximum H 74 (63–71), dL/maximum H 4.04 (3.57–3.77), S-1 L 89 (68–79), S-1 W 10 (7–9), L/W ratio 8.9 (9.71–8.77), S- 2 length 89 (68 –82), S-2 W 16 (12–14), L/W ratio 5.5 (5.66–5.85), distance S-1-2, 18.2 (13–15), L ratio S-1/2 1 (1–0.96); I-L-6 dL 156 (132–141), HB 22 (17–19), dL/HB ratio 7 (7.76– 7.42); length ratio I-L-5/6 1.91 (1.7–1.9).

Male ( Fig. 3 )

Measurements – Idiosoma L 560–588, W 431–459. Coxal shield L 266–296; Cx-III W 409–343; Cx-I+II mL 74–87, Cx-I+II lL 152–188. Genital field L/W 93/101–106/114, genital plate L 76–85, gonopore L 71–82, Ac-1–3 L: 14–15, 13–14, 13–14. Palp: total L 295–319; dL/H, dL/H ratio: P-1 29/28, 1.03–34/33, 1.03; P-2 59/48, 1.22–69/53, 1.3; P-3 59/30, 1.96–68/38, 1.78; P-4 95/28, 3.39– 111/34, 3.26; P-5 29/10, 2.9–37/13, 2.84; length ratio P-2/P-4 0.62–0.62.

Gnathosoma – vL 119–141; chelicera total L 213–248, basal segment L 149–174, claw L 59– 74, L ratio basal segment/claw 2.52–2.35.

Legs – I-L-5 dL 143–171, vL 113–129, dL/vL ratio 1.26–1.32, maximum H 48–55, dL/maximum H 2.97–3.1, S-1 L 58–68, S-1 W 6–7, L/W ratio 9.66–9.7, S- 2 length 52–61, S-2 W 7–10, L/W ratio 7.42–6.1, distance S-1-2, 7.92–9.88, dL ratio S-1/2 1.1–1.1; I-L-6 dL 89–104, HB 18–21, dL/HB H ratio 4.9–4.95; length ratio I-L-5/6 1.6–1.6.

Etymology Named for its occurrence in the Khuzestan province of Iran.

Remarks

Atractides (Atractides) khuzestaniensis sp. nov. are close to A. baderi Schwoerbel & Sepasgozarian, 1976 , A. (A.) hormozganus Pešić et. al., 2012 and A. (A.) nikooae Pešić, 2004 by sharing striated dorsal integument; small acetabula; unsclerotized dorsal muscle attachments; smooth excretory pore and Vgl-1 not fused to Vgl-2. However, the new species differs from A. baderi , A. hormozganus and A. nikooae based on the dentate and slightly concave anterior margin of pregenital sclerite vs. simple in A. baderi , A. hormozganus and A. nikooae ; P-4 sword seta (inserted closer to proximal ventral hairs in A. khuzestaniensis vs. inserted halfway between ventral hairs in A. baderi , close to distoventral hair in A. hormozganus and near the distoventral hair in A. nikooae ); however the new species can easily be distinguished from all other species by pregenital with anterior margin dentate and slightly concave.

ventral view; d. I-L-5 and -6; e. Palp, medial view. Scale bars: 100 μm.

Figures

Figure 1. Atractides khuzestaniensis sp. nov. (female holotype) – a. Coxae, genital field and ventral glandularia; b. Idiosoma, dorsal view; c. Genital field. Scale bars: 100 μm.

Figure 2. Atractides khuzestaniensis sp. nov. (female holotype) – a. I-L-5 and -6; b. Palp, medial view; c. Chelicera, lateral view. Scale bars: 100 μm.

Figure 3. Atractides khuzestaniensis sp. nov. (male paratype) – a. Genital field; b. Chelicera, lateral view; c. Idiosoma,