Yamatentomon satsuma, Nakamura, 2025

Yamatentomon satsuma sp. nov.

Figs. 1 View FIGURE 1 , 2 View FIGURE 2 ; Table 1

Materials examined. Holotype female (NSMT-Ap 737), Kinbô-zan , Daizaka , Kinbô-chô , Minamisatsuma-shi, Kagoshima Prefecture, Kyushu, Japan, 31°28'02"N, 130°23'03"E, elev. 570 m, evergreen broad-leaved forest dominated by Lithocarpus edulis , 9-XII-2007, K. Ishii et al. leg GoogleMaps . Paratypes: three males (NSMT-Ap 738–739) ( SMNH Ap-40891) , three females (NSMT-Ap 740–741) ( SMNH Ap-40892), same data as for holotype GoogleMaps .

Additional specimens examined: six males, seven females, same data as for holotype; three males, four females, Sakosetoyama, Higashibeppu, Chiran-chô, Minamikyushu-shi, Kagoshima Prefecture, Kyushu, Japan, 31°21'02"N, 130°28'05"E, elev. 230 m, mixed forest of evergreen and deciduous broad-leaved trees, 25- II- 2007, K. Ishii et al. leg.; one maturus junior , Kawanabe-tôge, Nozaki, Kawanabe-chô, Minamikyushu-shi, Kagoshima Prefecture, 31°27'07"N, 130°28'46"E, elev. 315 m, evergreen broad-leaved forest dominated by L. edulis and Castanopsis sieboldii , 10-XII-2007, K. Ishii et al. leg.; one male, Shigeta, Kamitakakuma-chô, Kanoya-shi, Kagoshima Prefecture, Kyushu, Japan, 31°29'32"N, 130°50'59"E, elev. 200 m, evergreen broad-leaved forest dominated by C. sieboldii , 8-XII-2007, K. Ishii et al. leg.

Diagnosis. Cephalic setae d6 absent; two slender sensilla on maxillary palpus; foretarsal sensillum b long, its apex surpassing base of γ 4; anterior setae A1 and A4' on tergite VII absent; accessory setae on thorax and abdominal segments I–VII all setiform and longer than one-third of P 1 in length.

Description. Body length 739 (754–923) μm in non-expanded condition. Head length 146 (135–146) μm; width 88 (85–88) μm; rostrum short, 9 (7–9) μm, LR = 17 (15–21) ( Fig. 1A View FIGURE 1 ); cephalic setae l3, l5, sd4, and sd5 all setiform and almost the same length, 10 (8–11) μm ( Fig. 1A, B View FIGURE 1 ); additional setae d6 absent ( Fig. 1A View FIGURE 1 ); setae d7, 14 (13–16) μm, slightly shorter than or subequal to sd 7 in length, 16 (15–18) μm; pores fp and cp present ( Fig. 1A View FIGURE 1 ). Two sensilla on maxillary palpus both slender and subequal in length, 9 (8–10) μm ( Fig. 1D View FIGURE 1 ). Praelabium with fringes; labial palpus with tuft of setae and broad sensillum ( Fig. 1C View FIGURE 1 ). Canal of maxillary gland with small calyx and minute appendix, posterior part short and thick, CF = 12 (11–13) ( Fig. 1E View FIGURE 1 ). Pseudoculus almost circular, 8 (8–9) μm × 8 (7–8) μm, with lever, PR = 18 (16–20) ( Fig. 1B View FIGURE 1 ).

Foretarsus ( Figs. 1F, G View FIGURE 1 ) 86 (83–89) μm; claw 37 (31–37) μm with one minute, often indistinct tooth, TR = 2.3 (2.4–2.7); empodium 3 (3–4) μm, EU = 0.09 (0.09–0.12); S-shaped seta slightly longer than claw, 39 (36–39) μm. Dorsal sensillum t1 baculiform, BS = 0.7 (0.6–0.7); t2 thin; t3 small and lanceolate. Exterior sensillum a long and proximally broadened, its apex surpassing base of sensillum d; b strikingly long, proximally slightly broadened, its apex surpassing base of γ4; apex of c reaching base of e; d situated halfway between c and e, slightly distal to t2, its apex reaching base of f; apex of e surpassing base of f; f and g close to each other, both apices slightly surpassing base of claw. Interior sensillum a' broad, level with t1, its apex almost reaching base of α4; b' absent; apex of c' reaching base of claw. Pores present near sensilla c and t3. Foretarsal setae β1 and δ4 long, setiform; β1, 20 (18–22) μm, about twice the length of δ1, and about half the length of β2, 39 (34–38) μm; δ4, 26 (25–29) μm, about three times longer than δ1; δ1–δ3 and δ5 short, setiform; δ1 and δ5 almost the same length, 9 (10–14) μm; δ2 and δ3, 16 (13–17) μm long, about 1.6 times longer than δ1. Middle tarsus 45 (44–45) μm, its claw 20 (20–21) μm; hind tarsus 51 (47–53) μm, its claw 23 (21–23) μm.

Body chaetotaxy as in Table 1 and Figs. 2A–H View FIGURE 2 . Pronotal seta 1 length 21 (19–22) μm, slightly longer than seta 2, 18 (16–18) μm. On mesonotum and metanotum, P1a 13 (11–14) μm long, P2a 13 (12–14) μm long, setiform, slightly longer than half the length of P 1 in length; P5a gemmate. A2 and M2 on prosternum and A2 on mesosternum and metasternum short setiform, length 7–8 (7–10) μm. Abdominal tergite I with four pairs of anterior setae ( A1, A2, A3, and A5); II–VI with five pairs ( A1–A5); VII with four pairs ( A2–A5), A4' absent; P3 on II–VII situated in the same row of P1, P2 and P4; II–III with eight pairs of posterior setae, P3a absent; IV–VII with nine pairs, P3a present, but often absent on IV–V; all accessory setae on I–VII setiform, 12–15 (11–16) μm, more than one-third the length of P1, 21–35 (22–37) μm. Accessory setae Pc and P1a on sternites I–VII similar to dorsal accessory setae; sternite VIII with single row of four setae.

Pronotum and prosternum without pores ( Figs. 2A, B View FIGURE 2 ); mesonotum with pores sl and al; metanotum with sl ( Fig. 2A View FIGURE 2 ); mesosternum and metasternum with a group of four (2‒5) adjacent sc ( Fig. 2B View FIGURE 2 ). Abdominal tergite I with pore psm; II–VI with psm and al ( Figs. 2C, G View FIGURE 2 ); VII with psm, psl and al ( Figs. 2D, H View FIGURE 2 ); VIII with psm with accompanying teeth ( Fig. 2E View FIGURE 2 ). Sternites I–V with single spm each ( Figs. 2F, G View FIGURE 2 ); VI with single spm and three (three or four) sam surrounded by anterior transverse line, VII with spsm and a group of adjacent four (three or four) sam surrounded by anterior connecting line ( Figs. 2H, J View FIGURE 2 ). Abdominal segment XII with one median dorsal pore and a pair of lateral pores.

Abdominal appendages II and III each with two setae; apical setae 13 and 12 (11–13) μm, respectively, subequal to or a little shorter than subapical setae, 15 (13–15) μm and 14 (14–18) μm, respectively, ( Fig. 1H View FIGURE 1 ). On abdomen VIII, striate band developed, striae distinct on its distal half ( Fig. 2E, I View FIGURE 2 ); small teeth scattered on anterior half ( Fig. 2E View FIGURE 2 ); comb consisting of 18 (17–21) teeth, with rounded margin, protruded posteriorly ( Fig. 1I View FIGURE 1 ). Female squama genitalis with pointed acrostylus ( Fig. 1J View FIGURE 1 ); male squama genitalis with 6+6 setae ( Fig. 1K View FIGURE 1 ).

Maturus junior (n = 1). Body length 630 μm in unexpanded condition. Head length 128 μm, LR = 39, CF = 12, pseudoculus 7 × 7 μm, PR = 18. Foretarsus 77 μm; claw 30 μm, TR = 2.5; empodium 3 μm, EU = 0.1; S-shaped seta not fully observed due to deformation. Shape and position of foretarsal sensilla similar to those of adult, BS = 0.6. Middle tarsus 38 μm, its claw 20 μm; hind tarsus 44 μm, its claw 22 μm. Body chaetotaxy shown in Table 1.

Chaetotaxic variation. Imago: P3a on tergites IV–V unstable. Of 17 specimens from Kinbô-zan, P3a of tergite IV asymmetrically absent on three specimens and absent on 12 specimens, and P3a of tergite V asymmetrically absent on four specimens and absent on five specimens. Of seven specimens from Sakosetoyama, P3a on tergite IV of three specimens asymmetrically absent, and absent on three specimens; two specimens without P3a on tergite V . One specimen from Shigeta with P3a absent on tergite IV and symmetrically absent on tergite V. P1 on tergite VI asymmetrically absent on one female. A1 asymmetrically present on tergite VII of one male and one female from Kinbô-zan. A1 asymmetrically present on tergite VII in one male, P1 asymmetrically absent on tergites V – VI of one female from Sakosetoyama .

Maturus junior with setae A4 on tergites V–VI and A1 on tergite VIII asymmetrically present.

Remarks. This new species resembles Y. kunnepchupi and Y. guoi in the absence of additional seta d6 on the head, anterior setae A4' on tergite VII and P3a on tergites II–III, as well as in the shape of the accessory setae on abdominal tergites I–VII. However, the present species differs from the aforementioned two species in the absence of A1 on tergite VII (present in both species). Additionally, it differs from Y. kunnepchupi in the length of foretarsal sensilla b (not reaching the base of γ 4 in Y. kunnepchupi ) and e (not surpassing the base of g). Furthermore, it differs from Y. guoi in the shape of the accessory setae on the mesonotum and metanotum (less than one-third of P 1 in Y. guoi ) and in the length of foretarsal sensillum c' (not reaching the base of the claw in Y. guoi ).

Distribution. Japan ( Kagoshima Prefecture, Kyushu).

Etymology. The specific name, a noun in apposition, is derived from the old native appellation for the region where the type locality and almost all collection sites are situated.