Atopogyrodactylus praecipuus Kritsky & Boeger & Patella 2020, n. sp.
Creators: name: Kritsky, Delane C.
name: Boeger, Walter A.
name: Patella, Luciana
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Platyhelminthes
Monogenea
Gyrodactylidea
Gyrodactylidae
Atopogyrodactylus
Atopogyrodactylus praecipuus

description: Atopogyrodactylus praecipuus n. sp.
(Figs. 1–10)
Type-host: Bristlenose catfish, Ancistrus sp. (Loricariidae).
Type-locality: Headwaters of the Rio Candeias south of Campo Novo de Rondônia and Road BR421, Rondônia, Brazil (10°49’8.67” S, 63°37’31.16” W to 10°47’12.35” S, 63°37’31.16” W), 15 December 2013.
Site on host: External surface.
Type specimens: Holotype, IOC 40095; 14 paratypes, IOC 40095, 40096, 40097, HWML 216037; 14 remaining paratypes in collection of WAB.
Etymology: The specific name (an adjective) is derived from Latin (praecipuus = peculiar, special, or extraordinary).
ZooBank registration: The Life Science Identifier (LSID) for Atopogyrodactylus praecipuus n. sp. is urn:lsid: zoobank.org:act: 549E2EBC-6063-48A3-AC2B-611ACFD54480.
Description: Greatest body width in anterior trunk at level of germarium; peduncle elongate, slender, slightly tapered posteriorly. Cephalic lobes moderately developed; head organs conspicuous. Testis subspherical to subovate; anterior seminal vesicle slightly smaller than posterior vesicle. Copulatory sac absent; MCO usually shaped as an inverted U. Accessory copulatory sclerite rod-shaped, subterminally expanded, with terminal spine. Germarium subspherical, with germinal cells surrounding distinct fertilization chamber; fertilization chamber containing oocyte. Oviduct with comparatively thick wall—often appearing sclerotized; Mehlis’ gland well developed, surrounding ootype; uterus containing a maximum of 1 egg; uterine pore lying to right of MCO, a transverse to diagonal slit with thickened rim. Proximal egg filament short, flared, about 1/10 total egg length; egg droplet prominent, an amorphous mass surrounding egg filament. Haptor cup shaped; anchor delicate, lacking well-defined basal roots, with tapered shaft, elongate recurved point; ventral haptoral plate ovoid, with thickened rim. Hook shank tapered to fine proximal ligament, lacking keel; hooklet flexed ventrally, with fine elongate closed point, ventrally leaning shaft, globose heel, truncate toe; FH loop about 1/4 shank length.
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1 Scientific names of hosts are current and follow Eschmeyer et al. (2019)
2 L = Loricariidae; P = Pimelodidae
3 Syn. Phanerothecium caballeroi, forma major of Kritsky & Thatcher (1977)
Measurements: Measurements of immature specimens follow those of the adults in brackets, respectively. Body 1,310 (968–1,530; n = 3) [706 (467–895; n = 10)] long; width 118 (116–123; n = 3) [83 (66–105; n = 10)] at level of germarium. Posterior pharyngeal bulb 59 (53–63; n = 3) [41 (35–49; n = 8)] wide; anterior pharyngeal bulb 45 (35–50; n = 3) [36 (31–45; n = 8)] wide. Accessory copulatory sclerite 30–31 (n = 1) [32 (28–35; n = 2)] long. Haptor 49 (41–57; n = 7) [42 (37–47; n = 7)] long, 50 (42–59; n = 5) [43 (39–55; n = 7)] wide. Ventral haptoral plate 32 (26–38; n = 5) [28 (24–36; n = 10)] long, 22 (18–29; n = 4) [21 (18–23; n = 7)] wide. Anchor 21 (17–23; n = 3) [17 (16–18; n = 9)] long. Hook 27–28 (n = 3) [27 (26–31; n = 11)] long; hooklet 5 (4–6; n = 3) [5 (4–6; n = 19)] long. Germarium 65 (49–80; n = 2) in diameter; testis [57 (49–69; n = 9)] long, [49 (38–62; n = 9)] wide. Egg 201 (192–207; n = 3) long, 66 (53–80; n = 3) wide.
Remarks: Atopogyrodactylus praecipuus n. sp. is the type species and currently the only member assigned to the genus.
description: Published as part of Kritsky, Delane C., Boeger, Walter A. & Patella, Luciana, 2020, Neotropical Monogenoidea. 63. Atopogyrodactylus praecipuus gen. et sp. n. (Gyrodactylidae), an oviparous gyrodactylid from the external surface of a bristlenose catfish Ancistrus sp. (Siluriformes: Loricariidae) from the Rondônian Amazon, Brazil, pp. 169-176 in Zootaxa 4732 (1) on pages 171-175, DOI: 10.11646/zootaxa.4732.1.8, http://zenodo.org/record/3662651