identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
C400832D40FD5DD98AE070A441F49D56.text	C400832D40FD5DD98AE070A441F49D56.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Myxobolus curriculus Yuan & Liu & Geng & Liu & He & Li & Xiang & Dai 2026	<div><p>Myxobolus curriculus sp. nov.</p><p>Figs 1, 2, 3, 4</p><p>Morphological description.</p><p>Upon rupturing the plasmodia, numerous myxospores were released and observed (Fig. 1 C). Mature myxospores were round in the valvular view, and lenticular in the sutural view (Fig. 1 C, Fig. 2), measuring 8.8 ± 0.2 (7.8–9.4) µm long, 8.3 ± 0.3 (7.5–9.3) µm wide, and 3.8 ± 0.3 (3.5–4.2) µm thick. Two equal, pyriform polar capsules were located anteriorly, with dimensions of 3.8 ± 0.2 (3.5–4.3) µm in length and 2.4 ± 0.3 (2.2–3.0) µm in width. Polar tubes formed 4–5 coils. Spores lacked a mucous envelope and intercapsular appendix but possessed 3–4 distinct posterior folds.</p><p>Species.</p><p>Myxobolus curriculus sp. nov.</p><p>Host.</p><p>Barbel chub Squaliobarbus curriculus ( Cyprinidae).</p><p>Site of infection.</p><p>Intestinal wall.</p><p>Plasmodia size.</p><p>Ellipsoidal, approximately 2 × 1.5 mm in size.</p><p>Prevalence.</p><p>32.35 % (11 / 34).</p><p>Locality.</p><p><a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=111.321915&amp;materialsCitation.latitude=27.729668" title="Search Plazi for locations around (long 111.321915/lat 27.729668)">Zi River</a>, Xinhua County, Loudi City, Hunan Province, China (27°43'46.8"N, 111°19'18.9"E).</p><p>Type material.</p><p>Specimens (fixed in 10 % formalin and 95 % ethanol), and digitized images of H &amp; E - stained tissue sections are deposited in the Museum of Hydrobiological Sciences, Hunan Agricultural University, China (accession numbers HNAU-CF-PAR-24061) .</p><p>Gene sequence.</p><p>A Partial SSU rDNA gene sequence (1731 bp) is deposited in GenBank under accession number PV 785691.</p><p>Etymology.</p><p>The species epithet derives from the species name of the host.</p><p>Remarks.</p><p>To date, seven Myxobolus species have been reported in barbel chub S. curriculus in China, including M. squamae Keysselitz, 1908, infecting the intestine, M. rotundatus Achmerov, 1956, infecting the intestinal wall, M. vastus Kudo, 1934, infecting the kidney and liver, M. squamosus Kudo, 1934, infecting the intestine, liver, and intestinal wall, M. pfeifferi Thelohan, 1890, infecting the gills, M. permagnus Wegener, 1910, infecting the gills, M. weishanensis Ma &amp; Chen, 1998 infecting the gills (Chen and Ma 1998). The new species is morphologically compared to these and distinguished by a combination of characters summarized in Table 1. Among them, M. squamae and M. vastus possessed ellipsoidal spores, while M. rotundatus and M. squamosus possessed round myxospores, as in the case of the new species. Furthermore, M. squamae could be easily differentiated from M. curriculus sp. nov. by bigger myxospore thickness and more folds. M. vastus possessed a bigger myxospore length and thickness, slightly more coils of polar tubes (5–6 vs. 4–5), an intercapsular appendix, and the absence of folds in the posterior. The plasmodia of M. rotundatus were smaller (2 × 1.5 mm vs. 0.193 × 0.181 mm) than those of the new species, but the size of the myxospore length and thickness was bigger. M. squamosus was recorded to be capable of infecting three different sites, while the present species was only found in the intestine of the host. In addition, M. squamosus differed from the novel species by more folds and bigger myxospore thickness (5.8–6.0 μm vs. 3.5–4.2 μm). The infection sites for M. pfeifferi, M. permagnus, and M. weishanensis were gills, different from intestinal wall for M. curriculus sp. nov. M. pfeifferi was distinguished from the concerned species by bigger myxospores (10.8–14.4 × 9.2 – 9.7 × 6.6 – 7.4 μm vs. 7.8–9.4 × 7.5 – 9.3 × 3.5 – 4.2 μm) and polar capsules (6.0–7.2 × 3.3 – 3.6 μm vs. 3.5–4.3 × 2.0 – 3.0 μm), more turns of polar tubes and less folds in the posterior. M. permagnus and M. weishanensis could be easily differentiated from M. curriculus sp. nov. by different myxospore shapes (pyriform vs. round), bigger myxospore, and more turns of polar tubes (&gt; 7 vs. 4–5) (Table 1).</p><p>LS: Length of spores; WS: Width of the spores; TS: Thickness of spores; LPC: Length of polar capsule; WPC: Width of polar capsule; PFC: number of polar filament coils; Folds: number of valvular folds; Refs: references; –: absent.</p><p>Histopathological examination</p><p>Histopathological analysis indicated that the new species developed within the circular muscle layer of intestine (Fig. 3). A development gradient was evident, with mature spores concentrated centrally and immature stages peripherally (Fig. 3 C). Expanding plasmodia compressed adjacent muscle fibers and elicited the formation of a thin outer connective tissue capsule (Fig. 3 D, E). No evident muscle fiber atrophy, necrosis, mucosal damage, epithelial desquamation, or obstruction of the intestinal lumen was observed, and no significant inflammatory response was detected.</p><p>Molecular characterization</p><p>The SSU rRNA sequence obtained is 1,731 base pairs in length and has been deposited in GenBank (PV 785691). BLAST analysis did not match any available species sequence in GenBank, but exhibited high similarity with Myxobolus algonquinensis Xiao &amp; Desser, 1997 (AF 378335, 93.02 %) infecting the ovary of Notropis cornutus, Myxobolus muellericus Molnár, Marton, Eszterbauer &amp; Székely, 2006 (DQ 439808, 92.86 %) infecting the gills of Leuciscus cephalus L., Myxobolus diversicapsularis Slukhai, 1966 infecting the gills of Rutilus rutilus (GU 968199, 92.83 %), Myxobolus feisti Molnár et al., 2008 infecting the cartilaginous gill rays of R. rutilus (EU 598804, 92.66 %), Myxobolus abitus Li &amp; Nie, 1973 (MG 520367, 92.43 %) infecting the gills of H. molitrix, and M. pavlovskii (Akhmerov, 1954) Landsberg &amp; Lom, 1991 infecting the gills of H. molitrix and bighead carp Hypophthalmichthys nobilis Richardson (MG 520368, 92.26 %). Genetic distance analysis indicated that the distances between this sequence and those of the most closely related species ranged from 0.0765 to 0.1230 (Table 2).</p><p>Both BI and ML analyses yielded phylogenetic trees with highly similar topologies. Minor discrepancies were confined to variations in support values at certain nodes (Fig. 4). The phylogenetic tree is clearly divided into two major clades, Clade A and Clade B. Species within the Clade A were further divided into three subclades. Subclade Ⅰ mainly comprised species infecting diverse organs of cypriniform hosts in Hungary and Portugal, Subclade Ⅱ mainly consisted of species infecting gills of cypriniform hosts in several different countries, and Subclade Ⅲ mainly comprised species infecting different organs of cypriniform hosts in China, India and Hungary. The node separating Subclade I and Subclade II was moderately supported (BI = 0.86, ML = 60 %), while the node grouping Subclade III with the other subclades showed low support (BI &lt;0.50, ML &lt;50 %). The present species formed a sister lineage with M. dabryi infecting the gills of Chanodichthys dabryi, Bleeker, 1871, with strong support (BI&gt; 0.95, ML&gt; 95 %), M. abitus infecting the gills of Hypophthalmichthys molitrix, and M. tauricus infecting the pin bones and fins of Barbus barbus Linnaeus, 1758, and Luciobarbus bocagei Steindachner, 1864 within the subclade Ⅲ (Fig. 4).</p></div>	https://treatment.plazi.org/id/C400832D40FD5DD98AE070A441F49D56	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Yuan, Shen;Liu, Xinhua;Geng, Xiangchang;Liu, Wei;He, Mingye;Li, Deliang;Xiang, Jianguo;Dai, Wenjing	Yuan, Shen, Liu, Xinhua, Geng, Xiangchang, Liu, Wei, He, Mingye, Li, Deliang, Xiang, Jianguo, Dai, Wenjing (2026): Morphological and molecular characterizations of Myxobolus curriculus sp. nov. (Myxozoa, Myxobolidae) infecting the intestine of Barbel chub Squaliobarbus curriculus in China. Zoosystematics and Evolution 102 (3): 807-815, DOI: 10.3897/zse.102.191790
