Description

Description. Body length 1,079 μm. Head length 148 μm, width 98 μm, labrum not protruded; cephalic setae l 3, l 5 short setiform, 5 and 7 μm, respectively; sd 4 and sd 5 oblong microchaetae (Fig. 4 E), 3 μm; d 6 present; sd 7 1.6 times longer than d 7 (Fig. 4 A). Maxillary palpus with two broad sensilla on penultimate segment, dorsal and ventral sensilla similar to each other in shape and length, 8 μm (Fig. 4 B). Labial palpus with three setae and one sensillum (Fig. 4 C). Canal of maxillary gland simple, proximal part short and stout with large end dilatation (Fig. 4 D). Pseudoculus longer than wide, 12 μm x 9 μm, PR = 13 (Fig. 4 E). Pore fp present (Fig. 4 A) Foretarsus (Figs. 5 A, B) 97 μm, claw 22 μm, TR = 4.5, empodium 3 μm, EU = 0.1. Foretarsal sensilla a – g and a' broad; a, g and a' broader than other sensilla. Dorsal sensillum t 1 claviform, same level with α 3, BS = 0.5; t 2 thin, distal to d; t 3 small knob-like, its apex not pointed. Exterior sensillum a surpassing base of d; b, c, and d on nearly line; b subequal to c and d; c close to d, its apex reaching base of e; d surpassing base of e; e situated about halfway between γ 3 and α 5; f close to e; g at same level with t 3; apices of e, f and g surpassing tarsus. Interior sensillum a' slightly distal to t 1; b' absent; c' linear, its apex reaching base of claw. Single pore present between α 3 and a, and between t 3 and g, respectively. Seta β 1 sensillum-like, δ 1 – 5 short; δ 5 proximal to δ 4. Middle tarsus 36 μm, its claw 19 μm; hind tarsus 42 μm, its claw 20 μm. Body chaetotaxy as in Table 2 and Figs. 6 A – E, 7 A – D. On thoracic tergites II – III (Figs. 6 A, B), P 1 a and P 2 a oblong microchaetae (Fig. 6 C); A 2 and M 2 on sternite I – III short oblong, same as dorsal accessory setae (Fig. 6 D, E). Seven anterior setae (Ac, A 2, A 3, A 4) present on thoracic sternites II – III (Fig. 6 E). 1 and 2 on thoracic tergite I 20 and 13 μm; P 1, 1 a and P 2 on thoracic tergite II 15, 2 and 22 μm. Abdominal tergites I – V with three pairs of anterior setae (A 1, A 2, A 5); VI with four pairs (A 1, A 2, A 4, A 5); VII with three pairs (A 2, A 4, A 5) (Figs. 7 A, B); P 3 on abdominal tergites II – VI situated anterior to other posterior setae (Figs. 7 A, B). Posterior accessory setae on abdominal tergites I – VII oblong microchaetae and less than about 1 / 6 of P 1 in length, but P 1 a absent on VI; P 1 a nearer to P 1 than to P 2; P 2 a near to P 3 (Figs. 7 A, B). P 1 a on abdominal sternites I – VII oblong microchaetae, same as dorsal ones (Fig. 7 D); VIII with a single two of four setae. P 1, P 2 and P 2 a on abdominal tergite VI 20, 25 and 3 μm; P 1, P 1 a and P 2 on VII 24, 3 and 27 μm. Thoracic tergite II – III with pore sl (Fig. 6 A, B). Pore psm present on abdominal tergites I – VIII, those on VIII without accompanying teeth (Fig. 7 C); al on V – VII, lt on V – VI (Fig. 7 D). Sternites V – VII with spsm (Fig. 7 D). Abdominal appendage II – III each with two setae, apical seta about 1 / 3 of subapical one in length (Fig. 4 F). On abdomen VIII, striate band developed, striae distinct (Fig. 7 C); comb rectangular with 7 teeth (Fig. 4 G). Female squama genitalis with stout pointed acrostylus (Fig. 4 H).

Common Names

No common names available.

Taxonomic Hierarchy

Kingdom: Animalia

Phylum: Arthropoda

Class: Protura

Order: Protura

Family: Acerentomidae

Genus: Gracilentulus

Species: Gracilentulus microtrichus Nakamura, 2021