Pseudanisentomon donan Nakamura, 2010

Nakamura, Osami, 2010, Taxonomic revision of the family Eosentomidae (Hexapoda: Protura) from Japan 2701, Zootaxa 2701, pp. 1-109 : 12-13

Pseudanisentomon donan Nakamura sp. nov.

Figs. 5–6; Table 2

Type specimen. Holotype female ( NSMT –Ap 453), Kubura –dake, Yonaguni Island , Okinawa Prefecture, 150 m elevation, litter of a forest dominated by L. chinensis var. subglobosa , 19-V-2000, H. Mizushima leg.

Description. Body length 1138 µm. Head 131 µm long, 100 µm wide. Setae aa, pa and m4 present, sensilla as and ps present ( Fig. 5A); seta sp 1.3 times longer than p; sensilla pp distinct ( Fig. 5B), 2 µm long. Labral setae absent ( Fig. 5C). Seta rs inflated, equal to sr in length ( Fig. 5C). On maxillary palpus ( Fig. 5D) sensillum md longer than ml. On galea ( Fig. 5E) digits similar to each other in shape, O longest and I shortest. Mandible with two apical and one subapical teeth ( Fig. 5F). Clypeal apodemes indistinct. Pseudoculus oval, 16 µm long, with two longitudinal lines, three short lines, and some depressions ( Fig. 5G); PR = 8.

Foretarsus length ( Figs. 5H, I) 98 µm; claw 18 µm, TR = 5.7; empodium 17µm, EU = 1.0; sensillum s equal to claw in length. Sensillum t1 closer to α 3 than to α 3', BS = 1.0; t2 thin but not clearly seen; t3 slightly broadened; a reaching level of t1; b long, reaching nearly to base of β 6; c not reaching base of γ 3; d short and broadened, reaching base of α 5; e absent; f1 spatulate; f2 short and broadened; g rounded-spatulate and long; a' thin; b'1 thin, nearer to δ 3' than to δ 4'; b'2 thin; c' slender in distal part. Length of middle tarsus 43 µm, length of claw 15 µm; empodium short, less than 1/5 of claw length ( Fig. 5J); hind tarsus 55 µm, claw 16 µm, empodium long, about 2/3 of claw length ( Fig. 5K); on hind tarsus ( Fig. 5K) D2 and D4 spine-like, D4 more slender than D2; D5 a thick spine.

Tracheal camerae short ( Fig. 6A). Central lobe constricted in middle ( Fig. 6B). Laterostigmata II–IV distinct, without inner structure. On female squama genitalis ( Fig. 6C) caput processus thin and bent toward median of stylus, corpus processus not developed, filum processus short. Male unknown.

Chaetotaxy as in Table 2. On thoracic tergites II–III, P1a and P2a seta-like; P1a posterior to P1–P2; P2a about halfway between P2 and P3. P1a on abdominal tergite I, P1a and P2a on II–VI, and P2a on VII filiform and longer than P1; P1a on VII sensillum-like and about one-third length of P1, at hind margin ( Fig. 6D); on tergite VIII ( Fig. 6E) P1a' with basal dilatation and anterior to P2; P2a falcate.

Diagnosis. This new species is similar to Ps. meihwa ( Yin, 1965) , Ps. wanense Zhang, 1987 from China ( Yin, 1965, 1999; Zhang, 1987), Ps. babai ( Imadaté, 1964) , and Ps. ishiii Nakamura, 1996 from Japan ( Imadaté, 1964a, 1974b, 1995; Nakamura, 1996) in having foretarsus longer than 90 µm, foretarsal sensillum b'1, anterior setae on abdominal sternite VIII, and six setae on the sternites IX–X. However, the present new species and Ps. babai are distinguished from other three by the absence of labral setae (present in other three). This new species is different from Ps. babai in pseudoculus with longitudinal lines (no inner structure in Ps. babai ), the position of foretarsal sensillum b'1 closer to δ 3' than to δ 4' (halfway between δ 3' and δ 4' in Ps. babai ) and the short empodium on middle tarsus (about 1/3 of claw length in Ps. babai ).

Etymology. The specific name, a noun in apposition, is derived from the old native appellation of Yonaguni Island.

Distribution. Japan (Yonaguni Island, known from only the type locality).