Anacanthorus paradouradensis, Monteiro, Cassandra Moraes, Cohen, Simone Chinicz & Brasil-Sato, Marilia Carvalho, 2015

Monteiro, Cassandra Moraes, Cohen, Simone Chinicz & Brasil-Sato, Marilia Carvalho, 2015, New species and reports of dactylogyrids (Monogenoidea) from Salminus franciscanus (Actinopterygii: Bryconidae) from the upper São Francisco River, Brazil, Zootaxa 3941 (1), pp. 137-143 : 140

Anacanthorus paradouradensis sp. n.

( Figs. 4–6 )

Type locality. São Francisco River, near Três Marias Reservoir (18º12’32”S; 45º15’41”W), State of Minas Gerais, Brazil.

Site. Gills.

Specimens studied. Holotype, CHIOC 38023a and 14 paratypes, CHIOC 38021a–d, 38022a–c, 38023b–d, 38024a–d.

Etymology. The specific epithet, “ paradouradensis ”, refers to the similarity of the new species with A. douradensis .

Description. (Based on 14 specimens “in toto”). Body fusiform, 1,573 (1,082–2,422; n=13) long, (160–666; n=13) wide. Cephalic lobes well developed. Eyes 4, posterior pair with eyes slightly farther apart than anterior pair; accessory granules spread on cephalic region. Pharynx sub-spherical, 95 (80–110; n=5) in diameter. Haptor 148 (106–185; n=6) long, 200 (117–239; n=4) wide, slightly bilobed, with concave posterior border, 7 pairs of hooks and 2 pairs (1 dorsal, 1 ventral) of 4A’s. Anchors, bars absent. Hooks 22 (20–24; n=32), similar in shape and size, with depressed thumb, curved shaft, recurved point, shank proximally expanded with indented circular foramen; FH loop well developed, about 0.8 shank length. MCO 237 (225–258; n=11) long, a loose spiral with funnelshaped base, distal end flattened, expanded. Accessory piece 144 (125–180; n=11) long, articulated with base of MCO through proximal process, composed of single rod-shape section that bifurcates in two branches of similar size, with thin and blunt edges. Testis postgermarial, 188 (175–202; n=2) long; seminal vesicle elongate, a dilation of vas deferens; vas deferens looping around left intestinal cecum. Germarium 149 (137–162; n=2) long, 93 (92–94; n=2) wide, sub-ovate. Vitellaria in two bilateral fields of trunk, from pharynx to posterior region of testes, coextensive with intestinal ceca. Egg 65 (n=1) long, 47 (n=1) wide, oviduct and ootype not observed. Uterus convoluted, sclerotized. Metraterm with conspicuous wall, sclerotized.

Remarks. Anacanthorus paradouradensis sp. n. appears to be more similar to A. douradensis . The male copulatory organ and accessory piece of the new species resemble the same structures in A. douradensis . In Anacanthorus paradouradensis sp. n. the accessory piece is half the total length of the MCO, while in A. douradensis these structures have almost the same length. In both species, the accessory piece bifurcates into two branches: A. paradouradensis sp. n. these branches have similar length, while in A. douradensis they have different lengths.

Figures

FIGURES 1 – 6. Sclerotized structures of Anacanthorus spp. from Salminus franciscanus Lima & Britsky from São Francisco River, Brazil. Figs 1 – 3. Anacanthorus adkruidenieri sp. n. 1. Copulatory complex (dorsal view). 2. Hook. 3. 4 A; Figs 4 – 6. Anacanthorus paradouradensis sp. n. 4. Copulatory complex (dorsal view). 5. Hook. 6. 4 A.