Eudigraphis huadongensis Yang & Bu, 2025

Yang, Si-Qi, Bu, Yun, Nunes Godeiro, Nerivania, Gao, Yan & Jin, Ya-Li, 2025, A new species of Eudigraphis (Diplopoda, Polyxenida, Polyxenidae) from East China, with embryonic and post-embryonic development observations, and mitogenomic and genetic divergence analyses, ZooKeys 1247, pp. 63-88 : 63-88

publication ID	https://doi.org/10.3897/zookeys.1247.155348
publication LSID	lsid:zoobank.org:pub:5475679A-3522-4C74-A9CD-7096C73D897F
DOI	https://doi.org/10.5281/zenodo.16324099
persistent identifier	https://treatment.plazi.org/id/151F673C-248A-588E-89EF-6B346E8E1B4B
treatment provided by	ZooKeys by Pensoft
scientific name	Eudigraphis huadongensis Yang & Bu
status	sp. nov.

Treatment

Eudigraphis huadongensis Yang & Bu sp. nov.

Figs 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7 , 8 View Figure 8 , 9 View Figure 9 , 10 View Figure 10 , 11 View Figure 11 , 12 View Figure 12 , 13 View Figure 13 , Tables 1 View Table 1 , 2 View Table 2 , 3 View Table 3 , 4 View Table 4 , 5 View Table 5 , 6 View Table 6

Material examined.

Holotype: • female (slide no. JS-WX-PX 2022012 ) ( SNHM), China, Jiangsu Province, Wuxi, Daji Mountain , alt. 5 m, 31°32’N, 120°12’E, 2022-X-26, coll. Y. Bu. GoogleMaps Paratypes (30 females, 11 males): • 1 female (slide no. JS-WX-PX 2021001 ), 1 male (slide no. JS-WX-PX 2021002 ), ibidem, 2021-VII-8, coll. Y. Bu GoogleMaps ; • 11 females (slides no. JS-WX-PX 2022003 – JS-WX-PX 2022008 , JS-WX-PX 2022010 – JS-WX-PX 2022011 , JS-WX-PX 2022013 – JS-WX-PX 2022015 ), 1 male (slide no. JS-WX-PX 2022009 ), ibidem, 2022-X-26, coll. Y. Bu GoogleMaps ; • 2 females (slides no. SH-TMS-PX 2020001 , SH-TMS-PX 2020002 ), China, Shanghai, Tianma Mountain , alt. 99 m, 31°4’N, 121°9’E, 2020-VII-31, coll. S. Q. Yang, Y. L. Jin & Y. Bu GoogleMaps ; • 3 female (slides no. SH-TMS-PX 2021002 , SH-TMS-PX 2021003 , SH-TMS-PX 2021005 ), 1 male (slide no. SH-TMS-PX 20210004 ), ibidem, 2021-IX-25, coll. Y. L. Jin, S. Q. Yang, Godeiro N. N. & Y. Bu GoogleMaps ; • 6 females (slides no. JS-SZ-PX 2023004 – JS-SZ-PX 2023005 , JS-SZ-PX 2023007 – JS-SZ-PX 2023008 , JS-SZ-PX 2023013 – JS-SZ-PX 2023014 ), 6 males (slides no. JS-SZ-PX 2023003 , JS-SZ-PX 2023006 , JS-SZ-PX 2023009 – JS-SZ-PX 2023012 ), Jiangsu Province, Suzhou, Shoutaohu Park , alt. 7 m, 31°17’N, 120°31’E, 2023-IV-14, coll. Y. Gao & Y. Bu GoogleMaps ; • 5 females (slides no. JS-SZ-PX 2023023 – JS-SZ-PX 2023027 ), Jiangsu Province, Suzhou, Lingyan Mountain , alt. 30 m, 31°16’N, 120°31’E, 2023-IV-15, coll. Y. Gao & Y. Bu GoogleMaps ; • 2 females (slides no. ZJ-HZ-PX 2023004 – ZJ-HZ-PX 2023005 ), 2 males (slides no. ZJ-HZ-PX 2023009 – ZJ-HZ-PX 2023010 ), Zhejiang Province, Huzhou, Changxing , alt. 211 m, 31°1’N, 119°47’E, 2023-IV-30, coll. Y. Gao & Y. Bu. GoogleMaps

Additional specimens examined.

Stadium I: • 7 individuals (slides no. SH-TMS-2020004 – SH-TMS-20200010 ), China, Shanghai, Tianma Mountain , alt. 99 m, 31°4’N, 121°9’E, 2020-VII-31, coll. Y. L. Jin & S. Q. Yang GoogleMaps . Stadium II: • 3 individuals (slides no. JS-WX-PX 2018023 – JS-WX-PX 2018025 ), China, Jiangsu Province, Wuxi, Daji Mountain , alt. 5 m, 31°32’N, 120°12’E, 2018-X-8, coll. Y. Bu GoogleMaps ; • 1 individual (slide no. JS-TMS-PX 2018036 ), China, Shanghai, Tianma Mountain , alt. 99 m, 31°4’N, 121°9’E, 2020-VII-31, coll. Y. Bu GoogleMaps ; • 2 individuals (slides no. JS-WX-PX 2021005 , JS-WX-PX 2021008 ), ibidem, 2021-VII-8, coll. Y. Bu GoogleMaps ; Stadium III: • 6 individuals (slides no. JS-WX-PX 2021014 – JS-WX-PX 2021019 ), China, Jiangsu Province, Wuxi, Daji Mountain , alt. 5 m, 31°32’N, 120°12’E, 2021-IX-3, coll. Y. Bu GoogleMaps . Stadium IV: • 5 individuals (slides no. JS-WX-PX 2018014 – JS-WX-PX 2018018 ), China, Jiangsu Province, Wuxi, Daji Mountain , alt. 5 m, 31°32’N, 120°12’E, 2018-X-8, coll. Y. Bu GoogleMaps ; • 1 individual (slide no. JS-WX-PX 2021011 ), ibidem, 2021-IX-3, coll. Y. Bu GoogleMaps . Stadium V: • 6 individuals (slides no. JS-WX-PX 2018006 – JS-WX-PX 2018011 ), China, Jiangsu Province, Wuxi, Daji Mountain , alt. 5 m, 31°32’N, 120°12’E, 2018-X-8, coll. Y. Bu GoogleMaps . Stadium VI: • 3 individuals (slides no. JS-WX-PX 2018004 , JS-WX-PX 2018005 , JS-WX-PX 2018012 ), China, Jiangsu Province, Wuxi, Daji Mountain , alt. 5 m, 31°32’N, 120°12’E, 2018-X-8, coll. Y. Bu GoogleMaps . Stadium VII: • 2 females (slides no. JS-WX-PX 2018001 , JS-WX-PX 2018003 ), 1 male (slide no. JS-WX-PX 2018002 ), China, Jiangsu Province, Wuxi, Daji Mountain , alt. 5 m, 31°32’N, 120°12’E, 2018-X-8, coll. Y. Bu GoogleMaps ; • 1 female (slide no. SH-XSS-PX 2017001 ), China, Shanghai, Sheshan Mountain , alt. 100 m, 31°6’N, 121°12’E, 2017-V-10, coll. Y. Bu & Y. L. Jin GoogleMaps .

Diagnosis.

Eudigraphis huadongensis sp. nov. is characterized by three long bacilliform sensilla, one conical sensillum and one setiform sensillum on the sixth antennal article, two long bacilliform sensilla, one conical sensillum and one setiform sensillum on seventh antennal article; posterior vertex trichome groups with 11–16 sockets in anterior row and 7–13 sockets in posterior row; 12 slender sensilla on lateral palp of gnathochilarium and 20 or 21 conical sensilla on the medial palp; 2 + 2 lamellae and 5 + 5 clypeo-labral setae on the labrum. The mandible has 14 branched comb teeth, ten rows of simple comb teeth, three longitudinal groups of intermediate sensilla, 14 serrate limbs, one smooth limb, 13 salivary ostioles, seven molar processes and seven molar combs. The leg setae have a coniform pleated base. The telson has 11–17 ornamental trichomes on each side dorsal to the caudal bundle; hooked caudal trichomes with a maximum of eight hooks.

Description.

Adult with 13 pairs of legs, body length 3.4 mm on average (3.0– 3.6 mm, n = 45, holotype 3.4 mm), caudal bundle 0.4–0.5 mm (Fig. 2 View Figure 2 ).

Coloration. Body evenly yellowish brown dorsally, pale yellow ventrally. Head with one dark brown transverse band on vertex connecting with red-brown eyes. Antenna with articles IV – VIII dark brown, with the basal three articles milky white. Legs variable in color, with last four or five podomere sections pale purple, basal sections white or purple. Body trichomes yellow-brown and caudal bundle trichomes grey to brown (Figs 2 View Figure 2 , 9 View Figure 9 ).

Head length 314 μm on average (270–450 μm, n = 45), width 500 μm on average (400–600 μm, n = 45) (Fig. 5 A View Figure 5 ), each side with eight ommatidia: five dorsal and three lateral ones (Figs 3 A View Figure 3 , 5 B View Figure 5 , 7 H View Figure 7 ). Vertex with two posterior trichome groups separated by a large medial gap, each group arranged in two close adjacent rows, anterior row with large trichome sockets, posterior row with small trichome sockets (Figs 3 A View Figure 3 , 5 A View Figure 5 , 5 G View Figure 5 , 5 H View Figure 5 ). Holotype has 14 sockets on both sides of anterior row, and ten sockets on both sides of posterior row (Figs 3 A View Figure 3 , 5 G View Figure 5 , 5 H View Figure 5 ). Paratypes with 11–16 sockets in anterior row and 7–13 in posterior row on each side.

Antennae length 420 μm on average (400–500 μm, n = 45), consist of eight antennal articles, article VIII shorter than VII (Fig. 5 C View Figure 5 ). Antennal article VI with three thick bacilliform sensilla: anterior Ta (10–16 μm), intermediate Ti (11–17 μm) and posterior Tp (11–17 μm), one setiform sensillum s (7–9 μm) between Ta and Ti, and one conical sensillum c (2–3 μm) close to Tp (Figs 4 A View Figure 4 , 5 F View Figure 5 , 7 I View Figure 7 ). Antennal article VII with two thick bacilliform sensilla Ta (11–17 μm) and Tp (10–16 μm), one setiform sensillum s (5–7 μm) between them, and one conical sensillum c (2–3 μm) close to Tp (Figs 4 A View Figure 4 , 5 F View Figure 5 , 7 I View Figure 7 ). Antennal article VIII with four sensory cones (5–8 μm).

Trichobothria. Trichobothrium a (posterior position), trichobothrium b (lateral position), and trichobothrium c (anterior position) with narrow cylindrical funicles, with sockets of equal size, forming an isosceles triangle with equal distance between ab and bc (Figs 3 A View Figure 3 , 5 D View Figure 5 , 7 H View Figure 7 ).

Labrum. Surface heavily covered by coarse granules, anterior margin with 2 + 2 lamellae on each side of the median cleft, clypeo-labrum with 5 + 5 short setae, 18–27 μm (Fig. 5 E View Figure 5 ).

Gnathochilarium. Lateral palp (90–107 μm) 2.1–2.3 times as long as medial palp (40–50 μm), each medial palp (MP) with 20 conical or slender sensilla, lateral palps (LP) each with 12 conical sensilla (Figs 4 B View Figure 4 , 5 I View Figure 5 ).

Mandible. Comb-lobe with a row of 14 branched comb teeth (BT) and ten rows of simple comb teeth (CT) (Fig. 6 A, B View Figure 6 ); intermediate plate with intermediate lobe (IL), intermediate sensilla (IS) pointed at apex and arranged in three longitudinal groups, and several fimbriate lamellae (FL) deeply incised into long pointed processes (Fig. 6 D View Figure 6 ); proximal plate bearing molar plate (Fig. 6 C, D View Figure 6 ) consisting of 14 broad serrated limbs (SL) with stoutly chitinous spines at apices and one smooth limb (SmL), wide granulated zone, 13 salivary ostioles (SaO) arranged roughly in two rows (Fig. 6 C View Figure 6 ), seven molar processes (MPr) and seven molar combs (MC) with regularly arranged teeth.

Trunk composed of ten tergites, nine pleural projections and telson (Fig. 2 View Figure 2 ). Collum with trichome sockets arranged in two oval-shaped groups in lateral positions opposite each other, connected by a single posterior row of trichome sockets in the middle (Figs 3 B View Figure 3 , 7 A View Figure 7 ), with 50 + 48 trichome sockets in holotype (Figs 3 B View Figure 3 , 7 D View Figure 7 ), and five trichome sockets on each lateral protuberance in holotype (Figs 3 B View Figure 3 , 7 A View Figure 7 ), with 86–103 in total and five or six on lateral protuberance each side in paratypes (Table 2 View Table 2 ). Tergite II with 62 + 61 trichomes in holotype (Figs 3 C View Figure 3 , 7 B View Figure 7 ), 103–132 in total in paratypes connected by a continuous posterior row of trichomes. Tergites II – X exhibit a consistent pattern of trichome insertions. Tergite X with fewer trichomes than other tergites (Figs 3 D View Figure 3 , 7 C View Figure 7 ), 76 in holotype and 64–110 in paratypes. The number of trichomes for each tergite is given in Table 2 View Table 2 .

Legs. Leg 1 lacks tarsus 1. Chaetotaxy (setae on each leg article) (Table 3 View Table 3 ): coxa 1: one seta, coxa 2: two setae, coxae 3–13: 0–4 setae; prefemur with one seta; femur usually with one large, long seta and one short seta in similar shape (Fig. 4 E, F View Figure 4 ), short seta sometimes absent on legs 1 and 13; tibia with one short seta (Fig. 4 E, F View Figure 4 ), occasionally absent on legs 11–13; post-femur and tarsus 1 without seta, and tarsus 2 with one pointed seta. Large and long setae on legs with coniform pleated base (Figs 4 C View Figure 4 , 4 E View Figure 4 , 5 J View Figure 5 ). Pointed setae on tarsus 2 with acute triangular base (Figs 4 D View Figure 4 , 4 E View Figure 4 , 5 K View Figure 5 ).

Telotarsus short, with a robust and pointed claw, narrow posterior lateral process, equal to half length of claw, anterior setiform process longer than claw, and a large, triangular lamella (Figs 4 G View Figure 4 , 7 J View Figure 7 ).

Sex organ. Female with paired genital vulvae between coxa of leg 2, each consists of three plates: one large upper plate with six short setae, two small lower plates each with five setae (Fig. 7 F View Figure 7 ). Male with paired penes between coxa 2 and two pairs of coxal glands on coxal plates of legs 8 and 9, each penis with eight short setae (Fig. 7 G View Figure 7 ). All short setae on sex organs similar to the larger leg setae.

Telson. Ornamental trichomes arranged either side dorsal to the caudal bundle (Fig. 7 C View Figure 7 ), with 13 + 13 trichomes ‘ a’ (holotype) (Figs 4 H View Figure 4 , 7 E View Figure 7 ), and 11–17 trichomes ‘ a’ on each side in paratypes (some asymmetry present). All have a single trichome ‘ b’ and three trichome ‘ c’ with large protruding base sockets c 1, c 2 and c 3 arranged in a triangle (Figs 4 H View Figure 4 , 7 E View Figure 7 ). Circular indentation d present (Figs 4 H View Figure 4 , 7 E View Figure 7 ).

Caudal bundles composed of a bundle of uniform, long hooked trichomes (Fig. 7 C View Figure 7 ). Females with two latero-sternal bundles of trichome sockets of nest trichomes. Males without nest trichomes, but with two groups of large trichome sockets ventrally. Hooked trichomes with a maximum of eight hooks.

Variation.

Among 52 adults observed, the number of trichomes on head, tergites, and telson are fairly variable and usually asymmetrical. The posterior of the vertex varied with 11–16 sockets in anterior row and 7–13 in posterior row. The ornamental trichomes showed asymmetry between sides: 12 + 14 in one specimen, 13 + 12 in two specimens, 15 + 14 in four specimens, 16 + 17 in two specimens and 13 + 16 in one specimen. The clypeo-labrum with 6 + 6 setae was observed in two specimens, 5 + 4 setae in five specimens, 4 + 4 setae in five specimens. Medial palp gnathochilarium with 21 + 21 conical sensilla was observed in five specimens. On the female genital vulvae, 7–11 setae were observed on the upper plate in ten specimens instead of more common six setae, and six setae (instead of five) on one of the lower plates in five specimens.

Etymology.

The species was named after the Chinese words “Huadong” = “East China ” which is the region where all type specimens were collected.

Remarks.

Eudigraphis huadongensis sp. nov. is similar to E. sinensis , E. xishuangbanna , and E. taiwaniensis in having the same number of sensilla on antennal articles VI and VII, similar body color, and same number of sensilla on the medial palp of gnathochilarium. They can be distinguished by the number of sensilla on the lateral palp of gnathochilarium (12 in E. huadongensis sp. nov. and E. taiwaniensis vs 13 in E. sinensis , 17 in E. xishuangbanna ), mandible structures (one smooth limb on proximal plate in E. huadongensis sp. nov. vs two or three in others), labrum (with 2 + 2 lamellae in E. huadongensis sp. nov. and E. taiwaniensis vs 3 + 3 in E. sinensis , 3 + 3 or 4 + 4 in E. xishuangbanna ), shape of large seta on legs (coniform base without other affiliated structures in E. huadongensis sp. nov. vs oval base with spines, pubescence, or processes in Eudigraphis species), and number of hooks on caudal trichome (maximum eight in E. huadongensis sp. nov. vs maximum four or five in others). All seven species of the genus Eudigraphis are compared in Table 4 View Table 4 .