Anacanthorus maratininguensis, Santos Neto & Muriel-Cunha & Domingues, 2019

Santos Neto, João F., Muriel-Cunha, Janice & Domingues, Marcus V., 2019, New species of Anacanthorus (Dactylogyridae: Anacanthorinae) from the gills of Hoplerythrinus unitaeniatus and Erythrinus erythrinus (Characiformes: Erythrinidae) of the coastal drainage in the Eastern Amazon, Brazil, Zootaxa 4615 (2), pp. 303-320 : 308

Anacanthorus maratininguensis sp. n.

( Figs. 12–15 )

Type-host: Hoplerythrinus unitaeniatus (Spix & Agassiz) , Erythrinidae .

Site of infection: Gills.

Type-locality: Igarapé Maratininga—Moju River, municipality of Tailândia, Pará State, Brazil (02º27’55.7”S 048º53’27.6”W).

Other localities: Hoplerythrinus unitaeniatus (Prevalence: 100% of one host examined. Mean intensity: 5 parasites per host infected), Igarapé Cururutuia—Caeté River, municipality of Bragança, Pará State (1°4’44.55”S 46°44’18.54”W); H. unitaeniatus (Prevalence: 100% of three hosts examined; Mean intensity: two parasites per host infected), Igarapé Arinandeua—Guamá River, municipality of São Miguel do Guamá, Pará State (1°37’42.50”S 47°29’45.06”W).

Prevalence: 42% of three hosts examined.

Mean intensity: 3,33 parasites per host infected.

Specimens deposited: Holotype: CHIOC no. 40033 a. 8 paratypes: CHIOC nos. 40033 b–c, 40034 a–b; INPA no. 807; MPEG nos. 164–165. 10 vouchers: CHIOC nos. 40035 a–b, 40036 a–b; INPA no. 806; MPEG nos. 162– 163.

ZooBank registration: The Life Science Identifier (LSID) urn:lsid:zoobank.org:act:B94E19A2-2FAC-4C4A-84D4-04FE1EF2FF92 .

Etymology: The specific epithet refers to the affluent river’s name of the type locality of the species, Igarapé Maratininga.

Comparative measurements: Table 3 .

Description: (Based on nine specimens, six mounted in Hoyer’s, two mounted in Gomori trichrome, one mounted in Grey & Wess). Body fusiform 424 (310–492; n=9) long, excluding the haptor, 97 (72–125; n=9) wide at the height of germarium ( Fig. 15 ). Four cephalic lobes developed; three groups of head organs; cephalic glands not observed ( Fig. 15 ). Two pairs of ocelli, posterior pair farther than the anterior pair; accessory granules absent ( Fig. 15 ). Pharynx subspherical 33 (31–36; n=4) long, 32 (25–41; n=4) wide ( Fig. 15 ). Two intestinal caeca, confluent, posterior to the gonads ( Fig. 15 ). Genital pore not observed. MCO 45 (42–49; n=10) long, 13 (10–14; n=10) wide, sclerotized, tubular, with distal region more dilated than the proximal region, presenting a small projection in the form of a hook in the distal region ( Fig. 12 ); accessory piece absent ( Fig. 12 ). Seminal vesicle, uterus, and prostatic reservoir not observed. Gonads slightly overlapping ( Fig. 15 ). Germarium pyriform 40 (35–46; n=2) long, 22 (19–25; n=2) wide; testis oval 50 (49–50; n=2) long, 27 (22–31; n=2) wide ( Fig. 15 ). Peduncle elongated ( Fig. 15 ). Haptor 40 (28–50; n=6) long, 54 (30–82; n=7) wide ( Fig. 15 ). Similar 4A hooks 9 (9–10; n=3) long ( Fig. 14 ). Seven pairs of similar hooks 26 (24–27; n=6) long, blade relatively long and slightly curved; shank with proximal dilatation comprising ½ of its length 10 (9–11; n=6) long; point short and slightly curved, thumb short and erect ( Fig. 13 ). Hook filament delicate, extending until near the shank dilatation ( Fig. 13 ).

Remarks: Anacanthorus maratininguensis sp. n. is similar to Anacanthorus euryphallus Kritsky, Boeger & Van-Every, 1992 based on the MCO morphology. However, Anacanthorus maratininguensis sp. n. differs from A. euryphallus by the presence of a small projection in the form of a hook in the distal region of the MCO, absence of an accessory piece, and by the hook morphology. Anacanthorus euryphallus has the shank of the hook without proximal dilatation, whereas Anacanthorus maratininguensis sp. n. has proximal shank dilatation comprising ½ of the shank length.

Figures

FIGURES 8–15. Anacanthorus siphonocommus sp. n. 8. Holotype whole-mount (ventral); 9. Hook; 10. Hook 4A; 11. Male copulatory organ (MCO); Anacanthorus maratininguensis sp. n. 12. MCO; 13. Hook; 14. 4A hooks; 15. Holotype whole-mount (ventral). Fig. 8 scale of 50µm; Figs. 9–10 scale of 10µm; Fig. 11 scale of 25µm; Figs. 12–14 scale of 25µm; Fig. 15 scale of 50µm.