identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
E3C5D1D8B6D458C8BF1B654CAD77DB79.text	E3C5D1D8B6D458C8BF1B654CAD77DB79.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Prodistomum chumphonense Gilardoni & Ribas & Suwannarat & Poonlaphdecha 2026	<div><p>Prodistomum chumphonense sp. nov.</p><p>Type materials.</p><p>Holotype (MZB 2026-0001) and Paratypes (MZB 2025-7273, MZB 2026-0002 - MZB 2026-0009) were deposited in the Museum of Natural Sciences of Barcelona, Spain.</p><p>Type locality.</p><p>Thailand, Chumphon Province, Gulf of Thailand, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=99.40046&amp;materialsCitation.latitude=10.75066" title="Search Plazi for locations around (long 99.40046/lat 10.75066)">Khai Nao Beach</a> 10.75066°N, 99.40046°E</p><p>Type host.</p><p>Rastrelliger brachysoma (Bleeker, 1851) and R. kanagurta (Cuvier, 1816) ( Scombridae).</p><p>Site of infection.</p><p>Intestine.</p><p>Diagnosis.</p><p>Body elongated, cylindrical, slightly wider anteriorly. Tegument armed with minute spines along the forebody extension. Oral sucker subterminal, subglobular to weakly infundibuliform. Ventral sucker rounded, situated near the junction of the anterior and middle thirds of the body. Prepharynx long; pharynx oval, muscular. Esophagus long; pseudoesophagus indistinct. Intestinal bifurcation in the posterior third of the forebody; cacum extend to near the posterior extremity; uroproct absent. Testes two, entire, oval to spherical, tandem, situated in the mid to posterior hindbody. Cirrus sac elongate claviform, located in the anterior hindbody. External seminal vesicle saccular; internal seminal vesicle subglobular. Pars prostatica well developed. Genital pore antero-sinistral to the ventral sucker. Genital atrium distinct. Ovary pretesticular. Uterus preovarian. Vitellaria follicular, confined to the hindbody. Excretory vesicle tubular, extending anteriorly to the level of the intestinal bifurcation. Eggs large, operculate, light brown.</p><p>Etymology.</p><p>The specific epithet refers to Chumphon Province, Thailand, where the type material was collected.</p><p>Description.</p><p>(based on 10 whole mounted adult specimens) Figs 1, 2. Specimens present an elongate body, slightly wider anteriorly, cylindrical, 968 (879–1,051) µm long by 186 (141–248) µm wide at the level of the ventral sucker; body length / width ratio 5.2 (4.2–6.2). Tegument bearing minute spines from the anterior extremity to the level of the ventral sucker. Eye-spot pigment scattered in the anterior forebody. Forebody 347 (258–411) µm long, representing 36 % (25–43 %) of body length. Hindbody 622 (508–751) µm long. Oral sucker subterminal, subglobular to weakly infundibuliform, 49 (37–58) µm long by 47 (35–73) µm wide. Ventral sucker rounded to oval, median, situated near the junction of the anterior and middle thirds of the body, 51 (35–67) µm long by 55 (27–84) µm wide. Sucker width ratio 1: 1.3 (1.1–1.7). Prepharynx distinct, 68 (41–117) µm long. Pharynx oval, muscular, 31 (24–37) µm long by 34 (24–44) µm wide. Esophagus long, 68 (35–124) µm; pseudoesophagus not clearly differentiable. Intestinal bifurcation in the posterior third of the forebody. Cecum extend to near the posterior extremity; uroproct absent; postcecal distance 54 (35–79) µm. Testes two, spherical to oval, tandem, median, located in the third of the body; anterior testis 69 (58–91) µm long by 67 (46–84) µm wide; posterior testis 78 (67–90) µm long by 69 (47–87) µm wide. External seminal vesicle saccular, large, well developed. Cirrus sac elongate-claviform, median to submedian, 195 (172–226) µm long by 58 (41–70) µm wide, occupying anterior region of hindbody. Internal seminal vesicle oval, expanding anteriorly into well-developed pars prostatica surrounded by prostatic cells. Ejaculatory duct long, thick-walled, terminating in distinct, genital atrium, 59 (47–93) µm long by 50 (41–60) µm wide. Genital pore antero-sinistral to the ventral sucker. Ovary oval, pretesticular, 56 (45–73) µm long by 43 (33–57) µm wide. Seminal receptacle saccular, median, situated between the ovary and the anterior testis, sometimes overlapping adjacent gonads, 50 (37–71) µm long by 65 (47–82) µm wide. Laurer’s canal and Mehlis’ gland not observed. Uterus preovarian, intercecal. Metraterm muscular, approximately half the length of the cirrus sac. Vitellarium follicular, confined to the hindbody, extending anteriorly to the level of the ventral sucker (from its anterior to posterior margin) and posteriorly to near the posterior extremity, not reaching the body end. Eggs few (maximum 15 per specimen), oval, operculate, light brown, unembryonated, without filaments, 47 (34–57) µm long by 30 (24–37) µm wide. Excretory pore terminal. Excretory vesicle tubular, extending anteriorly dextral to gonads and ventral sucker, reaching the level of the intestinal bifurcation.</p><p>Comparisons.</p><p>Following the key provided by (Bray and Cribb 1996), Prodistomum chumphonense sp. nov. can be distinguished from congeners primarily by the restricted distribution of the vitellarium to the hindbody, the relative sizes of the oral and ventral suckers, the length of the prepharynx and esophagus, and the morphology of the terminal genitalia.</p><p>Among species of Prodistomum in which the vitelline follicles extend anteriorly into the forebody, the following taxa differ clearly from P. chumphonense sp. nov. in this character state: P. alaskense (Ward and Fillingham 1934), P. angelae (Bray and Cribb 1996), P. gaevskayae (Madhavi and Bray 2018), P. hynnodi (Yamaguti 1938), P. keyam (Bray and Cribb 1996), P. lichtenfelsi (Raychard et al. 2008), P. menidiae (Manter 1931), P. polonii (Bray and Gibson 1990), P. priedei (Bray and Merret 1998), P. santoshi (Yadav et al. 2022), P. siddiqi (Madhavi and Bray 2018), P. travassosi (Madhavi and Bray 2018), P. vinodae (Madhavi and Bray 2018), and P. waltairensis (Madhavi 1972) . In all these species, the vitellarium distinctly invades the forebody, whereas in P. chumphonense sp. nov. it clearly differs in having the vitellarium confined entirely to the hindbody, not reaching into the forebody. In addition, P. gracile (Bray and Gibson 1990) is readily distinguished by the excretory vesicle extending anteriorly to the mid-level of the esophagus.</p><p>Among species in which the vitellarium is restricted to the hindbody, P. girellae is readily distinguished by the presence of prominent gland cells associated with the external seminal vesicle (Bray and Cribb 1996), a feature absent in P. chumphonense sp. nov. and all other congeners. P. mohsini (Madhavi and Bray 2018) and P. pomatomi (Amato 1983) differ from the new species in possessing an esophageal / pseudoesophageal region distinctly longer than the prepharynx, whereas in P. chumphonense sp. nov. these regions are approximately equal in length. In contrast, in P. libyacum (Al-Bassel 2001) and P. tripathi (Yadav et al. 2022) the esophageal / pseudoesophageal region is markedly shorter than the prepharynx. Besides, the sucker size ratio further distinguishes the new species. In P. mohsini and P. tripathi, the oral sucker is larger than the ventral sucker, whereas in P. chumphonense sp. nov. the ventral sucker is consistently larger than the oral sucker (width ratio 1: 1.3).</p><p>Regarding P. orientale, the most morphologically similar species, most records in the literature with available morphometrical data (Table 1) describe the vitelline follicles as well separated from the posterior margin of the ventral sucker (Layman 1930; Yamaguti 1938; Linton 1940; Travassos et al. 1965; Lopez-Roman 1979; Fischthal 1980; Gupta and Gupta 1987; Bray and Gibson 1990; Al-Zubaidy and Mhaisen 2014; Sokolov et al. 2020); in the latter, only a drawing is provided. In contrast, in P. chumphonense sp. nov. the vitelline follicles extend anteriorly to the level of the posterior margin of the ventral sucker. Some descriptions attributed to P. orientale described by (Fischthal and Thomas 1970; Madhavi 1972; Madhavi and Triveni Lakshmi 2011; Jadgal et al. 2022) exhibit a vitelline distribution partially similar to that of the new species. However, these differ from P. chumphonense sp. nov. in other morphometrical characters. The specimens reported by (Fischthal and Thomas 1970) are wider than P. chumphonense sp. nov. (430 µm vs. 186 µm), and the vitelline follicles extend into intercecal spaces. Instead, the vitellarium of P. chumphonense sp. nov. is well separated in two branches composed by three lines of vitelline follicles. The study of (Jadgal et al. 2022) does not provide a detailed description, measurements, or drawings; however, the photographs show a larger pharynx and oral sucker, and a shorter prepharynx and esophageal / pseudoesophageal region.</p></div>	https://treatment.plazi.org/id/E3C5D1D8B6D458C8BF1B654CAD77DB79	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	Gilardoni, Carmen;Ribas, Alexis;Suwannarat, Nannaphat;Poonlaphdecha, Srisupaph	Gilardoni, Carmen, Ribas, Alexis, Suwannarat, Nannaphat, Poonlaphdecha, Srisupaph (2026): A new species of Prodistomum (Digenea, Lepocreadiidae) from Rastrelliger spp. (Scombridae) in the Gulf of Thailand. Zoosystematics and Evolution 102 (3): 845-852, DOI: 10.3897/zse.102.190596
