Acanthoatractis Jesus and Melo, 2024

Jesus, Ronald Ferreira, Nandyara, Bianca, Santos, Jeannie Nascimento dos & Melo, Francisco Tiago de Vasconcelos, 2024, Acanthoatractis xinguensis n. gen., n. sp. (Nematoda: Cosmocercoidea: Atractidae) parasite of yellow-spotted Amazon river turtle, Podocnemis unifilis Troschel (Testudines: Podocnemididae) in Brazilian Amazon, International Journal for Parasitology: Parasites and Wildlife 24, pp. 100961-100961 : 100961-

3.1. Acanthoatractis Jesus and Melo n. gen

Diagnosis: Cosmocercoidea . Atractidae . Body medium-sized, tapering anteriorly, tail short and pointed with cuticle finely longitudinally striated. Lateral alae absent. Cephalic end surrounded by eight bifurcated sclerotized structures (two subdorsal pairs, two dorsolateral pairs, two subventral pairs, and two ventrolateral pairs) shaped like single-ended wrench, arranged in circle. These sclerotized structures equal, positioned on opposite sides in both transverse and longitudinal planes. Oral aperture small, terminal, and rectangular, surrounded by two sclerotized pieces (one ventral and one dorsal); each piece with pointed ends and median portion with pair of hooks; two large lateral amphids present. Esophagus divided into two parts; anterior esophagus (corpus) with distal bulb muscular, posterior esophagus (isthmus), ending in nonvalvulated bulb; nerve ring encircling isthmus; excretory pore anterior to esophageal bulb. Male with nine pairs of caudal papillae; spicules unequal, only larger (left) one narrower in middle portion, lanceolate; gubernaculum absent. Female monodelphic, ovoviviparous with vulva close to anus.

Etymology: The name of the genus comes from the greek “acanth/o,” meaning spine or thorn, referring to the presence of spines on the cephalic end of the nematode.