The main island of Taiwan is composed of two biogeographic realms: The Indomalayan realm in lowland and the Palearctic realm in high mountain (Amorosi,
1989). Fourteen genera of the freshwater horsehair worms have ever been found in
these two biogeographic realms including Acutogordius (both), Beatogordius (Palearctic), Chordodes (both), Digordius (Palearctic), Euchordodes (both),Gordionus (both), Gordius (both), Lanochordodes (Palearctic), Parachordodes
(Palearctic), Paragordionus (Palearctic), Paragordius (both), Progordius (Palearctic),Semigordionus (Palearctic), Spinochordodes (Palearctic) (Schmidt-Rhaesa, 2012).
According to our collection, at least five species of freshwater horsehair worms live in Taiwan. They are Chordodes formosanus, Acutogordius formosanus n. sp., and
Gordius sp. collected by the free living adult stage and one unknown species collected
by only the cysts in aquatic hosts.Chordodes formosanus Chiu, 2011
Distribution: Taiwan: Xindian, Shimen (New Taipei City), Taipei Zoo (Taipei
City), Lujiaokeng Ecological Protected Area in Yangmingshan National Park, (Taipei City), Jiaushi (Yilian County), Taroko National Park (Hualien County), (Hsinchu City, Taiwan), Lyudao (Taitung County); Japan: Sakado (Saitama), Kijo, Miyazaki (Miyazaki) (Chiu et al., 2011; Chiu et al., 2016a; Appendix 4); Other locality where the worms have ever been seen: Shihtoushan (Miaoli County, Taiwan), Hengchun Township, Neipu (Pingtung County, Taiwan), the Kobe University (Kobe City, Japan).Host: Hierodula formosana, Hier. patellifera (Mantidae: Mantodea) (Chiu et al., 2011, 2016); Acromantis japonica (Hymenopodidae: Mantodea), Holochlora japonica, Leptoteratura sp. (Tettigoniidae: Orthoptera) (Appendix 4).
Adult morphology (Fig. 1): Body length of C. formosanus 43–440 mm, 0.7–1.5
mm in wide (widest); male generally longer than female. Cuticle usually dark-brown (but one white individual has ever been seen) with bright lengthwise regions on both dorsal and ventral sides; a darkly pigmented line on ventral side in most specimens.Some females brown in color with dark patches.
Anterior end tapered, same color as body with a white tip. Anterior end round with moderately flat areoles and short bristles on surface. Anterior surface smooth in some individuals.
Posterior end not lobed, slightly narrowed in male (Fig. 1E) but round and slightly swollen in female (Fig. 1D). Cloacal opening oval, located subterminal with circumcloacal spines in male (Fig. 1E) and on terminal end of female (Fig. 1D).
Male tail structured by a pair of oval regions without areoles posterior to cloacal opening, and paired oval bristlefields bearing bristles on the lateral side of cloacal opening; only few bristles scattered on around the cloacal opening (Fig. 1E). Bristles
in the bristlefields generally branched or unbranched in most individuals; shorter or thinner unbranched bristles also found in few individuals; one sample from host, A.
japonica, without paired oval bristlefields.
Entire body covered by six types of areoles (simple, tubercle, thorn, circumcluster, and two types of crowned areoles)
(Fig. 1A, B). Simple areoles
generally smooth on the surface but some with dots, grooves, or short bristles; most abundant covering most of body surface except anterior end and ventral side of posterior end. Some of the simple areoles significantly elevated in clusters of two to ten, and darker under light microscopy. Tubercle areoles and thorn areoles scattered among simple areoles, similar in shape but with a tubercle or a solid thorn, respectively, on latter or top of areoles. Thorn areoles much less abundant than tubercle areoles and absent in some samples. Solid thorn in the male thorn areoles longer than that in female. Crowned areoles (Fig. 1A, B, C, E,F) clustered in pair with a central tubercle in between and surrounded by 12–20
circumcluster areoles with short filaments on the apical surface. Clusters of crowned areoles and circumcluster areoles scattered over trunk except anterior and posterior ends. Each crowned areole structured by filaments originating from apical center and sidelong to edges. The apical filaments generally around 10–15 μm in length (short-crowned areoles), but crowned areoles arranged in two lines on ventral and dorsal midlines of the female structured with significantly longer apical filaments which usually longer than 200 μm (65.57–392.25 μm) (long-crowned areoles)(Fig.
1C). Long-crowned areoles bright in color in the alive female and makes two white
lines on ventral and dorsal surface. Abnormally smaller crowned areoles found on one male sample (Fig. 1G) from the host, A. japonica, extreme smaller than crowned areoles on other individuals (Fig. 1F).Immature stage (Fig. 2, 3): Egg strings stuck onto substrate or drifting on
bottom. Eggs nearly circular, around 30 μm in diameter. Egg strings white when laid and becoming light-brown within one day, turning dark-gray just before hatching. Egg strings collected in field stuck onto a rock (Fig. 3G), mostly brown to gray, or white as those just laid in laboratory.Larvae remained near egg strings after hatching, not active. Some larvae leave the eggs and accumulated on the water bottom. Larva nearly 50 μm in length which composed of preseptum, postseptum, and ectodermal septum between them (Fig. 2A).
Length of the preseptum and the postseptum nearly the same. A proboscis in the preseptum around 11 μm in length; movable when the larva is alive. A V-shaped pseudointestines in the postseptum visible under the light microscope. Under SEM, larvae superficially annulated. Three sets of hooks arranged in three rings on anterior preseptum. The outer and second ring relatively large; visible under the light microscope. Outer ring contains five single hook and one ventral double hook; six hooks on second ring located between each outer hook; inner ring contains at least three inner spines, but real number unknown. A proboscis appears inside the preseptum, ornamented with two sets of spines: nine spines on dorsal and ventral sides of the proboscis, and five small lateral papillae on left side. A pair of anterior and posterior terminal spines on posterior of the postseptum. Pseudointestine exterior opening centrally located between anterior terminal spines on the ventral body.
Cysts morphologically similar to the larva reared in the laboratory found in the field collected aquatic insects including larval chironomids, adult caddies flies (Chimarra formosana), and stoneflies (Kamimuria sp.). Larvae encysted almost the same shape with that of free-living stage except V-shaped pseudointestines not found
(Fig. 2B). Cyst wall only found in few individuals (Fig. 2B); some larvae dark in
color (Fig. 2C).
Diagnosis: The conspecific status of the adult described above are suggested by
their low genetic distances (Chiu et al., 2011, 2016a). The genetic distances among all the 39 samples in Chiu et al. (2011), 5 samples in Chiu et al. (2016a), and five samples from the "novel hosts" (see below) are from 0 to 0.019, which is significantly smaller than 0.168, the genetic distances between C. formosanus and its morphological similar species, C. japonensis (Chiu et al., 2011). The morphology ofC. formosanus and C. japonensis are similar that both of them are structured by the
same five types of areoles, but distinct by the sexual dimorphism in C. formosanus since the long-crowned areole is present only in the female while that is present in both sexes of C. japonensis (Baek, 1993; Schmidt-Rhaesa, 2004; Chiu et al., 2011).This slight difference might makes some C. formosanus samples to be ever considered as C. japonensis (Schmidt-Rhaesa, 2004).
The intra-species morphological variation of C. formosanus are first described in
Chiu et al. (2011) by their head surface, morphology of bristles in the bristlefields,
and the present of thorn areoles. In the samples collected from the non-Hierodula hosts showed additional differences included the absence, or smaller size of the bristlefields and the smaller size of the paired crowned areoles which makes them similar to their surrounded circumcluster areoles(Appendix 4). I believe these two
morphological differences are obvious enough to separate these samples into several species but it is conflicted to the result of molecular data. Despite the phylogeny restructured by molecular data can be also misled (e.g. biased model or method (Yangand Rannala, 2012)), I still tend to accept the result suggested by the molecular data
since there are still a few studies mentioned about the morphological variation of horsehair worms (Schmidt-Rhaesa and Geraci, 2006; Chiu et al., 2011).The immature stages of C. formosanus are morphological similar to the previous description of Chordodes including the egg strings stuck on substances, the similar length of the preseptum and the postseptum, the V-shaped pseudointestine, and the unfolded encysted larva (Hanelt and Janovy, 2002; Szmygiel et al., 2014), but the cyst wall is usually absent in the encysted larvae of C. formosanus. The cysts collected from the field were judged as C. formosanus by the similar morphology with larvae reared in the laboratory and the adult C. formosanus collected near the habitat of the infected paratenic hosts. Since there is no technique to amply the DNA sequence from the cyst inside paratenic hosts, the species status of these cysts are not supported by the molecular data. With the lack of morphological and molecular information, the species status of the cysts are also referred to the adult horsehair worms collected in the same river (Poinar et al., 2004). It might be some cryptic species in the cysts with similar morphology, but the survey of the cysts can still provide the valuable field information of the horsehair worms (see below).
Collecting experience (Fig. 3): Chordodes formosanus is the horsehair worm
most frequently seen in the low altitude in Taiwan. Before it is scientifically described, local residents in Taiwan have already know the animal emerging from the "large green mantid". The "large green mantid" means its main host, H. formosana (Fig. 3B,D, E, F) and H. patellifera (Fig. 3A). Among these two main hosts, H. formosana is
much more frequently met due to its significantly larger population than H. patellifera.Hierodula formosana is endemic to Taiwan whose adult always emerge in shrubs
during early summer (Chiu and Wu, 2008). The dead infected mantids are usually found to be killed on the road during the emerge season (Fig. 3B). Mature worms in the alive host is usually visible by the heads slightly emerging around the host anus(Fig. 3A). The free-living adult C. formosanus are usually found in the pool which is
active in the night (Fig. 3C). Hierodula patellifera is the additional host of C.
formosanus in Taiwan and the only known host in Japan. Adults of H. patellifera
emerge about two months later than H. formosana in the both countries. They are also frequently found to be killed on the road during the emerge season but the population is much smaller than that of H. formosana.The adult C. formosanus emerging from A. japonica, H. japonica, Leptoteratura sp., and nymphal H. formosana are rarely found. These horsehair worms are generally much smaller than that emerging from adults of Hierodula hosts. The hosts other than
Hierodula mantids might be accidently infected since Chordodes are usually the
parasite of mantids (Schmidt-Rhaesa and Ehrmann, 2001) and the infection in the aquatic paratenic hosts are not significantly increased after the emerge season of these hosts (Chiu et al., 2016a).Fig. 1. Adult of Chordodes formosanus. (A) Cuticular surface (female) with six types of areole. (B) Cuticular surface (male) with five types of areole under SEM.
(C) Ventral side of female body with both types of the crowned areoles. (D) Female tail. (E) Male tail. (F) Close view of the short-crowned areole. (G) Close view of the abnormal crowned areole on an extreme small adult male.
Bri, bristle; Cir, circumcluster areole; Clo, cloacal opening; Lc, long-crowned areole; Sc, short-crowned areole; Sim, simple areoles; T, central tubercle; Th, thorn areole; Tu, tubercle areole. (Modified from Chiu et al., 2011)
Fig. 2. Larvae and cysts of Chordodes formosanus. (A) Newly hatched free-living larva. (B-C) Cysts in the paratenic hosts (larval chironomids) with the general appearance (B) and the cyst attacked by the host immune response (C). EctoS, ectodermal septum; Ho, hooklet; PostS, postseptum; PreS, preseptum; PsI, pseudointestine gland; Rc, residual cuticle; Sty, stylet. (Modified from Chiu et
al., 2011 and Chiu et al., 2016a)
Fig. 3. Chordodes formosanus in the field. (A) Mature worm inside a male host,
Hierodula patellifera, with the visible head (arrow). (B) Dead host, H.
formosana, and worm on the road which are commonly seen during the
reproductive season. (C) The free-living adult males collected from the water.(D-E) Juvenile worms in the body cavities of the host, H. formosana. (F) Mature worm inside the host dying on the road. (G) Worm egg strings collected from a rock in the stream. (Modified from Chiu et al., 2011 and Chiu
et al., 2015)
Acutogordius formosanus n. sp.
Distribution: Taiwan: Xindian (New Taipei City), Fushan botanical garden,
Jiaushi (Yilian County) (Appendix 4); Lujiaokeng Ecological Protected Area in Yangmingshan National Park, (Taipei City) (Chiu et al., 2016a); Other locality where the worms have ever been seen: Xindian (New Taipei City), Taroko National Park (Hualien County).Host: Eugryllacris sp., Neanias magnus (Orthoptera: Gryllacrididae). Deflorita apicalis, Elimaea sp., Hexacentrus japonicus, H. unicolor, Isopsera sp., Kuzicus sp., Mecopoda elongata, Phaulula sp., Pyrgocorypha formosana, Sinochlora longifissa
(Orthoptera: Tettigoniidae) (Appendix 4).Adult morphology (Fig. 4): Body length of A. formosanus 133–428 mm,
0.4–1.1 mm in wide (widest). All individuals had ever been seen are light-brown (Fig.4A, B). The body surface is smooth. Cone-like bristles scatter on some samples are
visible under SEM (Fig. 4G).Anterior end columned and slightly narrowed at the tip (Fig. 4B, C); anterior tip white (white cap) and followed by a dark brown collar (Fig. 4B); white spots scatter on the brown collar of few samples. Anterior surface various among individuals under SEM as wrinkled, smooth (Fig. 4C), or smooth but wrinkled on the tip; short bristles scatter on some samples; boundary between white cap and dark brown collar unobvious (Fig. 4C).
Posterior end is divided into two tail lobes in the male (Fig. 4A, F) and columned and round in the female (Fig. 4H). Cloacal opening is oval, located subterminal anterior to the postclocal crescent in the male (Fig. 4D) and on terminal end of the female (Fig. 4H); circumcloacal spines not found. Male tail lobes tapered on tip (Fig.
4A, F, E); tip wrinkled or covered by moderately flat areoles with short spines among
areoles
(Fig. 4E); inner side tail lobe smooth (Fig. 4D); cone-shaped spines or flat
areoles scattered on base of some tail lobe behind postclocal crescent. Postclocal crescent located ventrally on base of tail lobes(Fig. 4A, D, F). Postclocal crescent
shape various among individuals as slightly curved, almost angled(Fig. 4D, F), and
semicircular(Fig. 4A); Semicircular postclocal crescent usually slender than curved
and angled ones(Fig. 4A); Postclocal crescents in few samples extend into the tail
lobes while most of them are anterior to the starting point of bifurcation of tail lobes.Tiny bristles randomly scatter over ventral side of the male posterior end in most individuals, while that in few males scatter only anterior of postclocal crescent or over the ventral posterior end but concentrative on tail lobes (Fig. 4F).
Immature stage (Fig. 5): Egg strings are generally irregular in shape and
deposited as short pieces (4.94–19.13 mm in length) without sticking onto substrate(Fig. 5B); they are white or light yellow in color. Eggs are oval-shaped with
28.79–34.67 µm in length and 24.04–27.71 µm in width.The newly hatched larvae near eggs preformed "worm form" (Fig. 5A) or "cyst form" as encysted larva in paratenic hosts (Fig. 5C). Worm form larvae (Fig. 5A) around 110 μm in length, postseptum tapering on tip and around 2.5 folds longer than preseptum. Proboscis in the preseptum around 11 μm in length. Pseudointestine in postseptum unequally subdivided oval which around two-thirds length and nearly the same width of the postseptum. Cyst form larvae folded their postseptum forming as oval shape which around 25 μm in length and 17 μm in width; proboscis obvious in worm form larvae with the similar length.
Under SEM (worm form larvae), larvae surface superficially annulated.
Ectodermal septum not distinguishable under both SEM and light microscope. Hooks arranged in three rings on anterior preseptum: outer ring contains five single hooks
and two ventral double hook; middle and inner rings contains six hooks and six inner spines located between each outer hook, respectively. Proboscis inside a sheath appearing inside the preseptum, ornamented with two sets of spines: seven larger spines on each of later sides arranged into two lines except the largest terminal spine;
seven smaller spines on dorsal side; no spine found on ventral proboscis. One large single posterior spine located on end of postseptum. Pseudointestine exterior opening on base of large single.
Cysts morphologically similar to the larva reared in the laboratory found in the field collected aquatic insects (larval chironomids (Chiu et al., 2016a), mayflies (Paraleptophlebia sp.), and stoneflies (Kamimuria sp.)) and snails (Physa acuta) (Fig.
5C, D, E); encysted larvae usually folded (Fig. 5C, E) with clear cyst walls (Fig. 5C)
or unfolded like the worm form larva (Fig. 5D). Unfolded encysted larvae are characterized by the long postseptum and the tapering posterior tip (Fig. 5D). Folded encysted larvae fold twice in the cyst wall; folding invisible after treated by KOH solution(Fig. 5C); proboscis visible in folded encysted larvae (Fig. 5C, E).
Pseudointestine not found in both folded and unfolded encysted larvae.
Diagnosis: The low genetic distances suggest the conspecific status among the
27 examined Acutogordius samples. The genetic distance among them was ranged from 0 to 0.0112(Appendix 4), which is similar to the intraspecific pairwise
distances of Gordius cf. robustus (0.64–2.63%)(Hanelt et al., 2015) and C.
formosanus (0–1.92%) (Chiu et al., 2011), and lower than the interspecific pairwise
distances among species of genus Gordius (8.0–24.3%)(Hanelt et al., 2015)
andChordodes (16.84%) (Chiu et al., 2011).
Acutogordius formosanus n. sp. is morphologically similar to A. protectus
Schmidt-Rhaesa and Geracu, 2006 by (1) the distributive pattern of tiny bristles onventral posterior end, (2) moderately flat areoles (rounded elevation) covering tail tips, and (3) cone-shaped spines scatter on the base of tail lobes of the male
(Schmidt-Rhaesa and Geraci, 2006), but distinct by small ornamentations on the
mid-body of Acutogordius formosanus n. sp. The relative location of the postclocal crescent and the tail lobes in the male are traditionally applied to be the diagnostic characteristic in the spices level of Acutogordius, but it is various in Acutogordiusformosanus n. sp. while both postclocal crescent extended into the tail lobes (similar
to A. acuminatus, A. feae, A. obesus, and A. sulawensis) and that is anterior to the starting point of bifurcation of tail lobes (similar to A. americanus, A. australiensis, A.doriae, A. incertus, and A. protectus) (Schmidt-Rhaesa and Geraci, 2006) are found.
The shape of the postclocal crescent is also various in Acutogordius formosanus n. sp., but it might be not only caused by the genetic variation, but also the mechanical factor from environment since most of the males reared in the water for reproduction show the angled postclocal crescent.
The cyst of Acutogordius formosanus n. sp. is usually coexisted with that of C.
formosanus in the low altitude aquatic environment but they are easy to be
distinguished. The encysted larvae of Acutogordius formosanus n. sp. fold twice in the clear cyst wall have never been seen in the C. formosanus and the unfolded encysted larvae are obviously different by the long postseptum and the tapering posterior tip.The cyst of Gordius horsehair worm is resembled to that of Acutogordius (Hanelt and
Janovy, 2002; Szmygiel et al., 2014). Nevertheless, it is still distinguishable in Taiwan
since the Gordius is only found in the high mountain (the altitude higher than 1200 m) and its larva is much larger than that of Acutogordius (see below).Collecting experience (Fig. 5): The Acutogordius horsehair worm is the
common species in the low altitude in Taiwan. Comparing with C. fomosanus, it isless noted, although its population might be similar or even larger than that of C.
fomosanus. Adult Acutogordius formosanus n. sp. is frequently seen in its definitive
hosts from mid May to late October, which is much longer than C. formosanus, but its population might be sensitive to the human disturbance of the environment (Chiu etal., 2016a)
and its definitive hosts are generally nocturnal which are not easy to be encountered. The range of the definitive hosts is wide which might potentially covers most orthopteran insects especially the family Gryllacrididae and Tettigoniidae, but it might be higher specific to the predators such as the raspy crickets. As the C.formosanus, heads of adult Acutogordius formosanus n. sp. can be found from the
posterior tips of the hosts (Fig. 4F) and the juvenile worms are sometimes visible from the translucent abdomen cuticle (Fig. 4G).In the environment with less human disturbance, cyst of Acutogordius is easy to be found in the aquatic insects. In the aquatic insects collected from Taroko National Park (Hualien, Taiwan) in August, 2011, the stoneflies (Kamimuria sp.) showed nearly 100% of the infection rate in both naiads (13/13) and adults (28/30), while in the adult mayflies the infection rate is significantly lower (11/140). In the same samples, cysts of Chordodes is only occasionally found in the stoneflies and never appeared in the mayflies.
Fig. 4. Adult of Acutogordius formosanus n. sp. (A) Ventral view of the male tail.
(B-C) Anterior end examined by the stereomicroscope (B) and SEM (C). (D) Close view of the postclocal crescent. (E) Moderately flat areoles on the tip of male tail lobes. (F) Close view of the ventral male tail. (G) Surface of the mid-body with cone-shaped spines. (H) Female tail.
Fig. 5. Immature stage of Acutogordius formosanus n. sp. (A) Newly hatched free-living larva. (B) Egg strings. (C-E) Cysts from the field-collected mayflies (C-D) and a snail (E). (F) Mature worm inside a female host,
Hexacentrus japonicus, with the visible head. (G) Juvenile worms inside a
male host, H. japonicus, which are visible from the translucent abdomen cuticle. EctoS, ectodermal septum; Ho, hooklet; PostS, postseptum; PreS, preseptum; PsI, pseudointestine gland; Rc, residual cuticle; Sty, stylet.Gordius sp.
Distribution: Taiwan: Shizhuo (altitude 1380-1400 msl), Dinghu (altitude
1680-1737 msl), Fenqihu (altitude 1405 msl) (Chiayi County); Xitou forest recreational area (altitude 1150 msl) (Nantou County); Hongshih forest road (altitude 1100-1300 msl) (Taitung County).Host: Unknown.
Adult morphology (Fig. 6): Body length of Gordius sp. usually longer than 600
mm, 0.8-1.5 mm in wide (widest). Most samples dark brown or black in color (Fig.6H, I); few individuals light-brown cuticle. Body surface smooth and mucous before
fixed by alcohol. Cuticle surface scattered by white spots (Fig. 6G) but not found under SEM (Fig. 6E). Cuticle surface generally smooth with short bristles scattering on some samples (Fig. 6E, F).Anterior end columned and round at the tip (Fig. 6D, H). Anterior tip white (white cap); a dark brown collar presents posterior anterior tip following with a vertical white stripe on the ventral (Fig. 6H). Under SEM, anterior end smooth with short bristles scattering on surface except the tip; boundaries of white cap, dark brown, and vertical white stripe are unobvious (Fig. 6D).
Posterior end divided into two tail lobes in the male (Fig. 6A) and columned, round in the female (Fig. 6C). Cloacal opening round, located subterminal anterior to postclocal crescent in male (Fig. 6A) and on terminal end of female (Fig. 6C); surface of cloacal opening covered by areoles in male (Fig. 6B); Circumcloacal spines not found. Male tail lobes round on tip (Fig. 6A, I); surface smooth with bristles scattering posterior the postclocal crescent (Fig. 6A). Postclocal crescent semicircular, located ventrally on male tail and extends into tail lobes (Fig. 6A, I).
Immature stage (Fig. 7): Egg strings white in color, irregular in shape and
deposited as short pieces (2.12–13.76 mm in length) without sticking onto substrate
(Fig. 7F). Eggs are round with 47.80–58.23 µm in diameter (Fig. 7A–D).
Newly hatched larvae nearly 170 μm in length. Postseptum tapered on tip and around 2.5 folds longer than preseptum. Proboscis in the preseptum around 13 μm in length. Pseudointestine in the postseptum unequally subdivided oval which around two-thirds length and nearly the same width of the postseptum (Fig. 7E).
Cysts morphologically similar to larva reared in the laboratory found in four of ten field collected mayflies, Ephemera orientalis (Fig. 7G, H). Larva encysted folds twice in the clear cyst wall; folding visible after treated by KOH solution (Fig. 7H).
Proboscis visible in the folded encysted larvae.
Diagnosis: The low genetic distances of partial COI sequences suggest the
conspecific status among the Gordius specimens collected from Taiwan. The genetic distance among the 5 samples was ranged from 0 to 0.0249, which is similar to the intraspecific pairwise distances of Gordius cf. robustus (0.64–2.63%), and lower than the interspecific pairwise distances among species of genus Gordius (8.0–24.3%)(Hanelt et al., 2015). These samples of Gordius sp. display many unique properties.
The areoles covering the surface of male cloacal opening has never been described in the known species (Schmidt-Rhaesa, 2012). The white spots which is likely to be the gland opening and the mucus on the body surface might be the first time to be described in the horsehair worm. Gordius sp. might be also one of the few horsehair worm able to survive and mate on the wet land instead of in the water, despite the females only laid eggs in the water during being reared in the laboratory. In addition, the horsehair worm reproduces in the winter is also rare among the species already described. These properties might suggest an undescribed species of Gordius with unique adaptation to the environment. However, as the less information on the
morphology of known Gordius spices and the small sample size of the samples examined, here I would like to first introduce them to the science and judge the species status after more information is collected.