taxonID	type	description	language	source
03B7591DFF91C038DF15A0409AF3F9D3.taxon	vernacular_names	[Japanese name: kagi-nashi-hada-mushi-ka]	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C038DF3AA0009A89F910.taxon	vernacular_names	[New Japanese name: kagi-nashi-hada-mushi-zoku]	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	description	(Figs 1, 2)	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	vernacular_names	[New Japanese name: Futo-tsuno-zame-kagi-nashi-hada-mushi]	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	materials_examined	Holotype. MPM Coll. - No. 25318. Paratypes. Four specimens (MPM Coll. - No. 25319), 4 specimens (KMNH IvR 600098 – 600101), and 4 specimens (KAUM-AT- 3327 – 3329).	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	description	Description. Body pyriform, 3051 – 3978 (3595; n = 12) long including haptor, 1939 – 2498 (2142; n = 13) wide at anterior margin of germarium. Haptor without sclerotized armature, diamond-shaped sucker to accommodate shape of host dermal denticle; lower half of haptor more muscular and thicker, deep inside, attaching to tip of dermal denticle of host; 546 – 696 (604; n = 12) long, 653 – 912 (739; n = 12) wide. Eyes absent. Mouth opening subterminal of anterior body; two small protrusions on anterior side of mouth; pharynx bowlshaped with center protruding anteriorly, 248 – 369 (313; n = 13) long, 303 – 425 (381; n = 13) wide; esophagus absent; bifurcate intestinal cecum with numerous diverticula leading laterally and two medial diverticula dorsal to the anterior portion of the testis, not confluent posteriorly. Testis subspherical, intercecal, midline at top of lower body, 432 – 729 (560; n = 13) long, 577 – 893 (668; n = 13) wide. Vas deferens exiting from anterior margin of testis, swelling to form seminal vesicle at left of seminal receptacle, extending anteriorly on dorsal side of vitelline reservoir, entering ejaculatory bulb ventrally. Ejaculatory bulb muscular, spherical to oval, not directly connected to penis but located ventral to base of the penis. Sclerotized tube extending from left side of ejaculatory bulb, turning once (n = 12) or twice (n = 1) to dorsal side, entering base of penis, and extending three-quarters of the penis length, 440 – 733 (582; n = 13) long. Penis weakly muscular, curved dorsoventrally, 294 – 507 (427; n = 13) long along curve; terminal quarter of duct not sclerotized. Germarium spherical to oval, intercecal, situated slightly right at mid-body level, 195 – 364 (234; n = 13) long, 205 – 455 (260; n = 13) wide. Oviduct arising from anterior part of germarium, receiving duct from posterior aspect of vitelline reservoir. Ovovitelline duct extending posteriorly, connecting duct from seminal receptacle, traveling anteriorly on dorsal side, and connecting with oötype base surrounded by Mehlis gland. Oötype traveling medially, opening ventrally at unarmed common genital pore located in upper third of body, at penis level. Vaginal pore unarmed, on ventral surface between left intestinal cecum and upper third of oötype, posterior to penis. Vaginal tube muscular, extending to seminal receptacle ventrally with slight bend. Seminal receptacle midbody, left of germarium. Egg ovate slightly angled, with long filament, 86 – 145 (110; n = 3) long, 64 – 94 (78; n = 3) wide without filament, in oötype.	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	biology_ecology	Type host. Shortspine spurdog Squalus mitsukurii Jordan and Snyder, 1903 (Squaliformes: Squalidae).	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	materials_examined	Type locality. The East China Sea off Kuchino-erabu Island (30 ° 25 ′ N, 130 ° 12 ′ E), Yakushima Town, Kagoshima Prefecture, Japan.	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	biology_ecology	Sites of infection. Body surface (dermal denticles).	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	etymology	Etymology. The new scientific name is from Ancient Greek words (myzō = suck + lepís = scale) and refers to the haptor of the new species holding the tip of host’s dermal denticle. The new Japanese name, “ futo-tsuno-zame ” refers to the host in Japanese, and “ kagi-nashi-hada-mushi ” means microbothriid.	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	materials_examined	Representative DNA sequences. INSDC accession numbers: LC 805883 (28 S rDNA, 1295 bp), LC 805884 (18 S rDNA, 1877 bp), LC 805885 (ITS 1 - 5.8 S-ITS 2, 909 bp), and LC 805886 (cox 1, 934 bp). Each sequence obtained from two paratypes (KMNH IvR 600100, 600101) were identical.	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF91C03FDF2BA0C39978F87A.taxon	discussion	Remarks. Microbothrium myzolepis n. sp. exhibits the characteristic morphological features inherent to the genus, including singular testes, diverticulated intestinal ceca, rounded germarium, and unarmed penis accompanied by a sclerotized tube (Nitta and Nagasawa 2017). This newly described species is distinct from M. lepidorhini by the vaginal pore situated posterior to the genital pore on the left side of the ventral body (vs. right: Guiart 1938; Brinkmann 1940, 1952 a). It differs from M. tolloi by the unsclerotized vagina (vs. sclerotized: Brinkmann 1952 b). The vagina of the new species displays a slight bend without sinusoidal or coiled attributes, but that of M. apiculatum was thick-walled and strongly muscular tube with tight sinuosity (Saint-Remy 1891; MacCallum 1926 a, b; Price 1938). In addition, the vaginal pole of M. myzolepis n. sp. opens at the posterior to the genital pore, while that of M. apiculatum opens at same level as genital pore (Saint-Remy 1891; MacCallum 1926 a, b; Price 1938). Microbothrium myzolepis n. sp. is separated from M. cirrhigalei n. sp. by the sclerotized tube associated with the penis completes one to two turns (vs. three) and the muscular vagina (vs. only the vaginal opening is muscular) (Table 3).	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF96C033DDC1A3459A61FD40.taxon	description	(Fig. 3) [New Japanese name: Hige-tsuno-zame-kagi-nashi-hadamushi]	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF96C033DDC1A3459A61FD40.taxon	materials_examined	Holotype. MPM Coll. - No. 25320. Paratypes. Four specimens (MPM Coll. - No. 25321), 6 specimens (KMNH IvR 600084 – 600089), and 4 specimens (KAUM-AT- 3318).	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF96C033DDC1A3459A61FD40.taxon	description	Description. Body lanceolate, 2041 – 2717 (2361; n = 15) long including haptor, 931 – 1292 (1144; n = 15) wide at anterior margin of testis. Haptor muscular sucker to accommodate shape of host dermal denticle, without sclerotized armature, attached to tip of dermal denticle of host, 240 – 359 (301; n = 15) long, 275 – 419 (352; n = 15) wide. Eyes absent. Mouth opening at terminal of anterior body; two protrusions on anterior side of mouth; prepharynx sometimes associated with small buccal cavity, surrounded by anterior glands on each side; pharynx pyriform, 147 – 283 (227; n = 15) long, 190 – 347 (281; n = 15) wide; esophagus short or absent; bifurcate intestinal cecum with numerous diverticula leading laterally, not confluent posteriorly. Testis subspherical, intercecal, midline at top of lower body, 357 – 641 (537; n = 15) long, 402 – 653 (519; n = 15) wide. Vas deferens exiting from anterior margin of testis, immediately swelling to form seminal vesicle at anterior of testis, extending anteriorly on dorsal side, curving along penis, and entering ejaculatory bulb. Ejaculatory bulb weakly muscular, spherical to oval. Sclerotized tube extending from left side of ejaculatory bulb, turning three times (n = 14), entering base of penis, and extending to penis tip, 838 – 1149 (980; n = 14) long. Penis weakly muscular, tapered, 150 – 218 (185; n = 15) long along the curve. Germarium spherical to ovoid, intercecal, slightly right side at mid-body level, 107 – 230 (157; n = 15) long, 118 – 189 (149; n = 15) wide. Oviduct arising from anterior part of germarium and receiving ducts from vitelline reservoir and seminal receptacle. Ovovitelline duct extending anteriorly, connecting with oötype base. Oötype with thick wall, rounded, opening ventrally at unarmed common genital pore located in upper quarter of body. Vaginal pore muscular, unarmed, on ventral surface between left intestinal cecum and middle of oötype at upper third of oötype. Vaginal tube not muscular, extending downward, turning right, anterior to seminal vesicle, running along anterior margin of seminal vesicle, and connecting to seminal receptacle. Seminal receptacle midbody, left of germarium. Egg ovate, with short filament, 107 – 138 (123; n = 4) long, 72 – 107 (85; n = 4) wide without filaments, in oötype.	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF96C033DDC1A3459A61FD40.taxon	materials_examined	Type host. Mandarin dogfish, Cirrhigaleus barbifer Tanaka, 1912 (Squaliformes: Squalidae). Type locality. Oita Marine Palace Aquarium (Umitamago). The other compatible fishes with C. barbifer in the tank had no infected any microbothriid during regular health check-ups; thus, the ancestors of type specimens were likely derived from the East China Sea off the Danjo Islands at 140 m depth, Higashi-Hama-machi, Goto City, Nagasaki Prefecture. Sites of infection. Body surface (dermal denticles).	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF96C033DDC1A3459A61FD40.taxon	etymology	Etymology. The specific name is derived from the generic name of the type host, Cirrhigaleus barbifer. The new Japanese name, “ hige-tsuno-zame ” refers to the host in Japanese, and “ kagi-nashi-hada-mushi ” means microbothriid. Representative DNA sequences. INSDC accession numbers: LC 805887 (28 S rDNA, 1297 bp), LC 805888 (18 S rDNA, 1860 bp), LC 805889 (ITS 1 - 5.8 S-ITS 2, 914 bp), and LC 805890 (cox 1, 426 bp). Each sequence obtained from two paratypes (MPM Coll. - No. 25321) were identical.	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
03B7591DFF96C033DDC1A3459A61FD40.taxon	discussion	Remarks. Microbothrium cirrhigalei n. sp. was assigned to the genus because of the presence of defined genus characteristics (see Nitta and Nagasawa 2017; Remarks of M. myzolepis n. sp.). The new species is distinguished from M. lepidorhini by the vaginal pore positioned on the left side of the ventral body (vs. right in M. lepidorhini: Guiart 1938; Brinkmann 1940, 1952 a). Microbothrium cirrhigalei n. sp. readily separated from M. tolloi by the vagina is devoid of sclerotization (vs. sclerotized in M. tolloi: Brinkmann 1952 b). The sclerotized tube associated with the penis of the new species completes three turns, but those of its congeners turn zero to two times (Table 3). Furthermore, the vagina of M. cirrhigalei n. sp. is not muscular (only the vaginal opening is muscular), while those of M. apiculatum and M. myzolepis n. sp. are muscular (Saint-Remy 1891; MacCallum 1926 a, b; Price 1938; Table 3). Molecular data comparison The genetic distance between the 18 S rDNA sequences of M. myzolepis n. sp. and M. cirrhigalei n. sp. was 0.7 %, M. myzolepis n. sp. and Leptocotyle minor (Monticelli, 1888) was 5.8 %, M. myzolepis n. sp. and H. japonica was 8.7 %, M. cirrhigalei n. sp. and L. minor was 5.8 %, and M. cirrhigalei n. sp. and H. japonica was 8.5 % (1852 bp). The genetic distance between the 28 S rDNA sequences of M. myzolepis n. sp. and M. cirrhigalei n. sp. was 2.1 % (1261 bp). The genetic distances of ITS 1 - 5.8 S-ITS 2 and cox 1 sequences between M. myzolepis n. sp. and M. cirrhigalei n. sp. were 4.8 % and 20.1 %, respectively; those between M. myzolepis n. sp. and H. japonica were 49.3 % and 28.6 %, respectively; and those between M. cirrhigalei n. sp. and H. japonica were 50.7 % and 30.7 % (819 bp and 387 bp), respectively. The pairwise sequence divergences among the microbothriid species for the 18 S rDNA, 28 S rDNA, ITS 1 - 5.8 S-ITS 2, and cox 1 sequences are summarized in Tables 4 – 6. Phylogenetic analysis The phylogenetic trees based on partial 28 S rDNA sequences are shown in Fig. 4. In accordance with the findings of Perkins et al. (2009) and Nitta and Nagasawa (2017), the tree utilized Calicotyle japonica Kitamura, Ogawa, Shimizu, Kurashima, Mano, Taniuchi, and Hirose, 2010 (Monocotylidae) as an outgroup. It is noteworthy that the topologies of the trees constructed through both ML and BI analyses exhibited congruence. Phylogenetic trees illustrated a distinct separation within the microbothriid lineage, resulting in the formation of two major clades. The first major clade encompassed species from Dermopristis Kearn, Whittington, and Evans-Gowing, 2010, Dermophthirius MacCallum, 1926, and Haplocotyle Nitta and Nagasawa, 2017, with a notable affinity between the species of the former two genera. The second major clade includes Pseudoleptobothrium Young, 1967, Asthenocotyle Robinson, 1961, Leptocotyle Monticelli, 1905, and Microbothrium. Microbothrium myzolepis n. sp. and M. cirrhigalei n. sp. were placed in the same clade.	en	Ota, Masato Nitta and Shogo (2025): Two New Species of Microbothrium (Monogenea: Microbothriidae) Parasitic on Japanese Squalids (Elasmobranchii: Squaliformes). Species Diversity 30 (1): 25-36, DOI: 10.12782/specdiv.30.25, URL: https://doi.org/10.12782/specdiv.30.25
