Nipponentomon jaceki, Shrubovych, Julia, 2009

Shrubovych, Julia, 2009, Nipponentomon jaceki sp. nov. from the Russian Far East (Protura: Acerentomidae, Nipponentominae), Zootaxa 2231, pp. 55-61 : 55-61

Nipponentomon jaceki sp. nov.

Figs. 1–27 , Tables 1–2

Material examined. Type material. Holotype female (slide 18.1a), litter under Acer sp., mixed forest, Mt. Khualaza, 550 m elev., Anisimovka, Livadiysky Range, Shkotovsky area, Primorski Kray, Russia (43°00'15'' North, 132°47'37'' East), 18. IX. 2004, leg. R. J. Pomorski. Eleven paratypes (4 females, 2 males, 2 maturi juniors, 3 larvae II), same data as holotype. Additional specimens: 10 females, 7 males, 5 praeimagos, 3 maturi juniors, and 1 larva II, litter under conifers and in decaying wood, mixed forest, Khualaza Mt., 700 m elev.; 11 females, 6 males, 3 praeimagos, litter under Alnus and Betula spp., 1270 m elev.; 1 female, 1 praeimago, 1 maturus junior, and 1 larva II, in litter under Acer , Ulmus , and Fraxinus spp., lowland deciduous forest at western end of Anisimovka, 19. IX. 2004, leg. R. J. Pomorski, M. Potapov.

Other material: 1 male, decaying wood of Pinus koreensis, Pidan Mt. , 800 m elev., Livadiysky Range, Shkotovsky area, 20. IX. 2004, leg. M. Potapov; 1 female, decaying wood, mixed forest, Ussuriysky reserve, Ussuriysky area, 5. X. 2004, leg. M. Potapov; 1 female, soil and mosses on cliff by sea shore, Care Mramorny, Kraskino, Khasansky area, 28. IX. 2004, leg. M. Potapov; 1 male, soil near Skvoznaya cave, Chondalaz Range, between Nakhodka and Partizansk, Partizansky area, 26. IX. 2004, leg. R. J. Pomorski.

The holotype (slide 18.1a), 22 females, 13 males, 7 praeimagos, 6 maturi juniors and 5 larvae II (slides 18.1–18.18) and other materials are deposited in the collection of the State Museum of Natural History of the National Academy of Sciences of Ukraine, L’viv ( SMNH); 4 females, 2 males, and 1 praeimago (slides 18.19, 18.21) in the collection of M. Potapov; 4 females, 2 males, and 1 praeimago (slides 6546 and 6547) in the collection of the Institute of Systematics and Evolution of Animals of the Polish Academy of Sciences ( ISEA), Kraków, Poland.

All specimens are mounted as microscopic slides in the medium of Faure ( Dunger & Fiedler 1989).

Description. Head setae long, additional (a) and postpseudocular (pp) setae present, dorsal side with 2+2 modified setae, indicated of the arrows in Fig. 1 . Rostrum very short, rounded ( Fig. 2 ). Pseudoculus round, with distinct short lever, PR 14–19 ( Fig. 3 ). Maxillary gland with large, densely granulated calyx; posterior filament short, with bilobed posterior dilation, CF 5.1–7.3 ( Fig. 4 ). Maxillary palps short, dorsal sensillum shorter and thicker than lateral sensillum ( Fig. 5 ). Labial palps well developed, with broad basal sensillum ( Fig. 6 ). Labium with smooth inner margin.

Main setae on nota long ( Fig. 9 ). Seta M on meso- and metanotum of medium length (seta P1 about 2 times longer than M). Accessory setae P1a and P2a modified, short, stumpy, truncated at the tip; P3a and P4 subequal in length and shape, short, unmodified; P5 a small sensillum. Length ratio of P1: P1a: P2 on mesonotum as 7.6–8.7: 1: 9–10.1. Mesonotum and metanotum with pores al and sl. Prosternum without seta A2, metasternum with 7 anterior setae, A1 absent ( Fig. 10 ). Setae M2 on prosternum and A2 on meso- and metasternum sensillum-like, rounded at the tip; other setae of normal shape. Prosternum with no pores; meso- and metasternum each with single median pore. Chaetotaxy formula as in Table 1.

TABLE 1. Body chaetotaxy of Nipponentomon jaceki n. sp. a a Boldface: primary and secondary setae; normal print: tertiary setae; italics: setae added in adult stage. Setae in parentheses present or absent in maturus junior.

Foretarsus without sensillum b’; sensillum t1 filiform; t3 leaf-like; d, f and c’ long, nearly seta-like; other sensilla slender ( Figs. 7, 8 ). Sensillum d close to e. Sensillum b slightly shorter than a and c; g and e shorter than t2; a’ slightly distal to t2, reaching to base of t3. Setae β 1 of normal shape, slightly longer than δ 1 and the same length as δ 2; δ 4 modified, short, thick and truncated on the apex. Claw very long and slender, with small single inner tooth. Empodial appendage short. Length formula of sensilla: t3 <(e = g) <t1 <(b = a’) <(a = c), t2 <d <(c’ = f). BS 0.6–0.8, TR 2.0–2.4, EU 0.1–0.2. Pores present on exterior part of foretarsi near base of sensillum c and sensillum t3.

Chaetotaxy of abdomen as in Table 1. Accessory setae on urotergites I–V sensillum-like ( Figs. 12, 13 ). Urotergites VI–VII usually lacking P1a; P2a longer and thinner than on preceding tergites, of normal shape ( Fig. 13 ). Pore psm present on urotergite I–VIII, psl on V–VII, al on II–VII anterior to level of A5. Comb-like structures on lateral side of terga absent ( Fig. 14 ).

Abdominal legs with 4, 2, 2 setae. Subapical seta of second and third legs nearly as long as apical seta. Accessory setae on urosternites I–VII unmodified. Urosternites I–VII with single median pore, situated in posterior part (between and slightly anterior to setae P1) on I–IV, and in anterior part of sternites (near Ac) on V–VII ( Figs 11, 15 ).

Abdominal segment VIII with distinct striate band ( Figs.16, 17 ); tergite and sternite with two irregular rows of small, scattered granules ( Figs. 18, 19 ); comb VIII with concave hind margin, composed of 8–10 irregular, slender teeth ( Fig. 20 ). Pore psm with several surrounding teeth ( Fig. 18 ), other pores absent. Hind margin of sternite smooth, that of laterotergite with small teeth ( Fig. 19 ). Seta 1a on urotergite IX subequal to seta 1 in length. Seta 2a on urotergites IX and X shorter than the other setae, spine-like. Lateral part of urotergite IX–XI with distinct ciliated lines ( Fig. 21 ). Hind margin of urotergite IX–XI with distinct ciliation ( Fig. 22 ). Hind margin of urosternite IX smooth in middle part, with distinct ciliation laterally. Hind margin of urosternite X distinctly ciliated. Dorsal lobe of telson with single median pore ( Fig. 23 ), ventral lobe with 1+1 obscure anterolateral pores. Hind margin of dorsal lobe smooth ( Fig. 18 ), that of ventral lobe with delicate serration in central part ( Figs. 19, 22 ).

Male squama genitalis with 7+7 setae, additional setae (add) present in adult and praeimago ( Figs. 24, 25 ). Female squama genitalis short, with blunt, bilobed acrostyli ( Figs. 26, 27 ).

Observed chaetal variability of adults as follows (n = 46): on mesonotum, asymmetrical absence of P2a (on 1 specimen); on metanotum, asymmetrical presence of P2a’ (2); on urotergite VII, asymmetrical presence of P1a (3); on urosternite I, absence of Pc (1); on urosternite IV; absence of Ac (1); on urosternite VI, absence of Ac (3); on urosternite VII, absence of Ac (1).

Etymology. Nipponentomon jaceki is named for my friend and colleague R. Jacek Pomorski.

Diagnosis and discussion. Nipponentomon jaceki sp. n. is similar to N. aureitarsum (Ewing, 1940) , N. bifidum Rusek, 1974 , N. macleani Nosek, 1977 , N. pembertonense Bernard & Biechele, 2008 , N. bidentatum Nakamura, 2004 and N. khabarovskense Nakamura, 2004 ( Tuxen 1964, Rusek 1974, Nosek 1977, Nakamura 2004), in that it does not have a prominent rostrum. The present new species differs from these related species in the shape of comb VIII (with distinctly concave hind margin), from N. aureitarsum , N. bifidum , N. macleani , N. bidentatum , and N. pembertonense in the lack of seta P1a on urotergite VII, from N. bifidum in the structure of the maxillary gland (in N. bifidum the calyx with additional appendage granulated), from N. macleani in the position of sensilla a’ and c’ on foretarsus (in N. macleani the sensillum a’ close to t3, and the sensillum c’ posteriorly to t3), and from N. bidentatum in the presence of additional setae (add) on head.

The new species is most similar to N. khabarovskense . The two species differ in the shape of comb VIII (in N. jaceki the hind margin is concave, in N. khabarovskense the hind margin is straight), shape of the maxillary sensilla (in N. khabarovskense they are seta-like, in N. jaceki they are sensilliform - rounded on the tip and thicker), and in the length of foretarsal sensilla e and g (long in N. khabarovskense and short in N. jaceki ).

Measurement Adult Praeimago Maturus junior Larva II

Figures

FIGURES 1 – 8. Nipponentomon jaceki sp. nov. 1 — head, dorsal view (arrows show modified setae; pp = postpseudocular seta, a = additional seta); 2 — rostrum; 3 — pseudoculus; 4 — canal of maxillary gland (A—lateral view, B—dorsal view); 5 — maxillary palp; 6 — labial palp; 7 — foretarsus, exterior view (arrows show pores); 8 — foretarsus, interior view. Figs. 3 and 4 A—holotype, Figs. 7 and 8 — paratype 18.3 b, others—paratype 18.2 a. Scale bars: 20 µm.

FIGURES 9 – 15. Nipponentomon jaceki sp. nov. 9 — nota (sl = sublateral pore; al = anterolateral pore); 10 — prosternum (A) and metasternum (B); 11 — urosternites I – III; 12 – urotergites I, V, VII (psm = posteromedial pore; psl = posterosublateral pore); 13 — accessory seta P 2 a on urotergites and urosternites V – VII; 14 — anterolateral pore on urotergite VII; 15 — urosternites V and VII. (Arrows show pores). Figs. 10 A, 13, 15 — paratype 18.2 a, 14 B—paratype 18.3 a, 14 C—paratype 18.3 b, others—holotype. Scale bars: 20 µm.

FIGURES 16 – 27. Nipponentomon jaceki sp. nov. 16 — “ striate band ”, dorsal view; 17 — “ striate band ”, ventral view; 18 — urotergites VIII—XI & telson; 19 — urosternites VIII—XI & telson; 20 — comb VIII; 21 — lateral structures on urotergites IX—XI; 22 — hind margin of urotergites IX – XI and of urosternites IX—telson; 23 — telson, dorsal view; 24 — male squama genitalis (add = additional seta); 25 — squama genitalis of praeimago; 26 — female squama genitalis; 27 — acrostyli. (Arrows show pores). Figs. 18, 20, 21 — holotype, 24 — paratype 18.4 a, 25 — paratype 18.4 d, 27 — paratype 18. 5, others—paratype 18.2 a. Scale bars: 20 µm.