Homidia longiantenna sp. nov.

Figs 1, 2-8, 9-11, 12-17, 18, 19, 20–27, Tables 2, 3

Type material.

Holotype • ♀ on slide, China, Guangxi Zhuang Autonomous Region, Guilin City, Longsheng Autonomous County, Huaping Natural Reserve, Tianping Mountain, 31 - V- 2023, 25 ° 37 ′ 52 ″ N, 109 ° 54 ′ 47 ″ E, 935.4 m asl, sample number 1281. Paratype • ♀ on slide, same data as holotype. All collected by Y-T Ma.

Description.

Size. Body length up to 3.02 mm.

Coloration. Ground colour pale yellow; eye patches dark blue; scattered brown pigment present on body, especially tibiotarsus, lateral and posterior parts of Abd. IV, sometimes Ant. III – IV and Abd. II – III also with brown pigment (Fig. 1).

Head. Antenna not annulated and 0.98–1.07 times length of body. Ratio of Ant. I – IV as 1.00 / 1.24–1.50 / 1.06 – 1.30 / 2.06 – 2.60. Distal part of Ant. IV with many sensory chaetae and normal ciliate chaetae, apical bulb bilobed (Fig. 2). Sensory organ of Ant. III with two rod-like chaetae (Fig. 3). Sensory organ of Ant. II with 3 (4) rod-like chaetae (Fig. 4). Eyes 8 + 8, G and H smaller than others, interocular chaetae as p, r, t mes. Dorsal chaetotaxy of head with four antennal (An), five median (M) and eight sutural (S) mac (Fig. 5). Prelabral and labral chaetae as 4 / 5, 5, 4, all smooth, a 0, a 1 longer than a 2; labral papillae absent (Fig. 6). Basal chaeta on maxillary outer lobe almost as thick as apical one; sublobal plate with three smooth chaetae-like processes (Fig. 7). Lateral process (l. p.) of labial palp E differentiated, as thick as normal chaeta, with tip almost reaching apex of papilla E (Fig. 8). Labial base with MM 1 R 1 ReL 1 L 2, chaeta e smooth and other ciliate, R 1 sometimes absent, R 0.60–0.73 length of M; anterior post-labial chaetae slightly expanded (Figs 9–11).

Thorax. Tergal ms formula on Th. II – Abd. V as 1, 0 / 1, 0, 1, 0, 0, sens as 2, 2 / 1, 2, 2, 23, 3 (Figs 12, 18 – 20). Th. II with four medio-medial (m 1, m 2, m 2 i, m 2 i 2), three medio-sublateral (m 4, m 4 i, m 4 p), 30–38 posterior mac. Th. III with about 39–41 mac (Fig. 12). Coxal macrochaetal formula as 3 / 4 + 1, 3 / 4 + 2 (Figs 13–15). Trochanteral organ with 71–76 smooth chaetae (Fig. 16). Tenent hair clavate, 0.95–0.98 length of inner edge of unguis; unguis with three inner teeth, basal pair located at 0.38–0.39 distance from base of inner edge of unguis, unpaired tooth at 0.62–0.64 distance from base; unguiculus lanceolate, outer edge slightly serrate (Fig. 17).

Abdomen. Range of Abd. IV length as 9.00–9.30 times as dorsal axial length of Abd. III. Abd. I with 11 (a 1 a, a 1–3, m 2 i, m 2–4, m 4 i, m 4 p and a 5) mac. Abd. II with six (a 2, a 3, m 3, m 3 e, m 3 ea, m 3 ep) central, one (m 5) lateral mac. Abd. III with two (a 2, m 3) central, four (am 6, pm 6, m 7 a, p 6) lateral mac (Fig. 18). Abd. IV with two (as, ps) normal sens, 14–20 anterior, 6–7 (A 4–6, B 4–6, Ae 7, A 4 sometimes absent) posterior and 24–26 lateral mac (Fig. 19). Abd. V with three sens (Fig. 20). Anterior face of ventral tube not seen entirely, line connecting proximal (Pr) and external-distal (Ed) mac oblique to median furrow (Fig. 21); posterior face with five or eight distal smooth and numerous ciliate chaetae (Fig. 22); lateral flap with 7–8 smooth and 19–30 ciliate chaetae (Fig. 23). Manubrial plate dorsally with 14–15 ciliate mac and 3 (2) pseudopores (Fig. 24); ventrally with 33–41 ciliate chaetae on each side (Fig. 25). Dens with 54–78 smooth inner spines (Fig. 26). Mucro bidentate with subapical tooth larger than apical one; tip of basal spine reaching apex of subapical tooth; distal smooth section of dens almost equal to mucro in length (Fig. 27).

Etymology.

Named after its characteristic long antennae.

Ecology.

Found in the leaf litter.

Remarks.

The new species is characterised by the long antennae and the slightly expanded post-labial chaetae, and can be easily distinguished from all known species of Homidia. It is similar to the species H. apigmenta Shi, Pan & Zhang, 2010, H. pseudofascia Pan, Zhang & Li, 2015, and H. wanensis Pan & Ma, 2021 in the expanded post-labial chaetae and colour pattern, but can be separated from them by the long antennae and other characters. It is also similar to H. jordanai Pan, Shi & Zhang, 2011 in the long antennae, but significant differences exist between them, such as the post-labial chaetotaxy and central mac on Abd. III and other characters. The detailed character comparisons are listed in Table 2.