Thalassaphorura reducta Sun, Chen & Deharveng, 2010, sp. nov.
Creators: name: Sun, Xin
name: Chen, Jian-Xiu
name: Deharveng, Louis
Publisher: name: Zenodo
Year: 2010
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Entognatha
Collembola
Onychiuridae
Thalassaphorura
Thalassaphorura reducta

description: Thalassaphorura reducta sp. nov.
Figs 1, 17, 23, 29 & 35, Tab. 1.
Type material. Holotype male, 1 paratypes male, 5 paratypes female and 2 paratypes juvenile on slide, about 30 paratypes in alcohol. China: Guangxi: Fushui: Bapen Nature Reserve: 4.iii.2005, soil, berlese, Deharveng & Bedos leg. (CHIgx05–028)– ibid: 2 paratypes on slide, 25 paratypes in alcohol, 4.iii.2005, soil, berlese, Deharveng & Bedos leg. (CHIgx05– 0 16, –018) – ibid: 10 paratypes on slide, about 325 paratypes in alcohol, 4.iii.2005, litter, berlese, Deharveng & Bedos leg. (CHIgx05–011, –015, –019, –025) – Longzhou: Nonggang Nature Reserve: 3 paratypes on slide, about 50 paratypes in alcohol, 7.iii.2005, litter, berlese after sifting, Deharveng & Bedos leg. (CHIgx05–068).
Holotype and 11 paratypes on slide and many paratypes in alcohol in NJU; 12 paratypes on slide and many paratypes in alcohol in MNHN.
Description. Body length: females 0.85–0.95mm, males 0.65–0.80 mm. Body shape: cylindrical, Abd. III–IV more or less broadened. Body color: white in alcohol.
Pseudocelli formula as 32/122/33343 dorsally, 11/000/01000 ventrally, subcoxa 1 of legs I, II and III with 1, 1 and 1 pso respectively (Fig. 17). Parapseudocelli: 1+1 on sternum of Abd. I, near base of ventral tube (Fig. 35). Pseudopore formula as 00/011/11110 dorsally, 00/111/00010 ventrally.
S-chaeta formula as 11/011/222120 dorsally (Fig. 17). Sp present on head. S-microchaeta tiny and blunt, present on Th. II and III dorsally.
Head. Antennae short and distinctly segmented, 0.9–1.0 as long as head. Length ratio of antennal segments I: II: III: IV = 1: 1.5–1.7: 1.5–1.7: 2–2.2. Ant. I with 8–9 chaetae. Ant. II with 13 chaetae. Ant. III sensory organ composed of 5 papillae, 5 guard chaetae, 2 small rods and 2 smooth subequal clubs; lateral ms just behind sensory organ. Ant. IV subapical organite with apex globular; basolateral ms at about 2/5 length from base. Antennal base without distinct granulation. PAO composed of 15–19 simple vesicles arranged in 2 rows along axis of organ. Dorsal cephalic chaeta d0 present. 4+4 p-chaetae between posterior a-pso on head, p1 anterior to others. Mandible with strong molar plate and 4 apical teeth. Maxilla bearing 3 teeth and 6 lamellae. Maxillary palp simple with 1 basal chaeta and 2 sublobal hairs. Labral chaetae 4/142. Labial papillae of AC type, papillae A–E respectively with 1, 4, 0, 3 and 2 guard chaetae. Labium with 6 proximal, 4 (E, F, G and f) basomedian and 6 (a, b, c, d, e, e’) basolateral chaetae. Postlabial chaetae 4+4 along ventral groove.
Body chaetotaxy. Ordinary chaetae differentiated in meso- and macro-chaetae, ratio Sp: m1: P1 on Abd. V = 1: 0.8: 1.7 (Fig. 23). Th. I with 4–5+4–5 dorsal chaetae. Th. II–Abd. III respectively with 2–3+2–3 dorsal chaetae along median line. Abd. IV tergite with axial chaeta m0, Abd. V with a0, Abd. VI with a0 and m0 (Fig. 23). Th. I, II and III with 0+0, 1+1 and 1+1 chaetae respectively between legs. In females, subcoxa 1 of legs I, II and III with 2, 4, 4 chaetae, subcoxa 2 with 1, 4 and 4 chaetae respectively; in males, subcoxa 1 of legs I, II and III with 2, 4(3), 4(3) chaetae, subcoxa 2 with 1, 4(3), 4(3) chaetae respectively.
Appendages. Tibiotarsi I, II and III with 18 (9, 8, 1), 18 (9, 8, 1) and 18 (9, 8, 1) chaetae. Unguis without teeth. Unguiculus slender and pointed, 0.3–0.4 times in females and 0.2–0.3 times in males as long as inner edge of unguis, with narrow inner basal lamella (Fig. 29). Ventral tube with 1+1 anterior chaetae, 6+6 distal chaetae and 1+1 basal chaetae (Fig. 35). Furca reduced to a finely granulated area, with 4 small chaetae in two rows posterior to furcal rudiment.
Genital plate with 13–15 chaetae in females and 28–30 in males. Anal valves with numerous acuminate chaetae; each lateral valve with chaetae a0 and 2a1; upper valve with chaetae a0, 2a1, 2b1, c0, 2c1, 2c2. Anal spines without papillae, 0.2–0.25 times as long as inner edge of hind unguis (Fig. 23).
Ecology. In forest litter and soil.
Etymology. Named for the reduction on the number of pseudocelli.
Remarks. Bisexual species. The new species is easily distinguished by the reduction of pso on ventral side and very small AS. Males and females exhibit differences in the relative length of unguiculus and sometimes in the number of chaetae on subcoxae of legs I, II and III. The new species has the same number of pso on Th. II–III as alborufescens, bagnalli, butrosi, hera, kirgisica, moniezi and saccardyi. However, it is different from them by the dorsal and ventral pso formula and the number of chaetae on ventral tube.
description: Published as part of Sun, Xin, Chen, Jian-Xiu & Deharveng, Louis, 2010, Six new species of Thalassaphorura (Collembola, Onychiuridae) from southern China, with a key to world species of the genus, pp. 20-38 in Zootaxa 2627 on pages 33-34, DOI: 10.5281/zenodo.198236