Circumvitellatrema momota , Dronen, Norman O., Greiner, Ellis C., Ialeggio, Donna M. & Nolan, Thomas J., 2009

Dronen, Norman O., Greiner, Ellis C., Ialeggio, Donna M. & Nolan, Thomas J., 2009, Circumvitellatrema momota n. gen., n. sp. (Digenea: Cyclocoelidae: Cyclocoelinae) from a captive-hatched blue-crowned motmot, Momotus momota (Momotidae), Zootaxa 2161, pp. 60-68: 64

publication ID 10.5281/zenodo.188988

persistent identifier

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scientific name

Circumvitellatrema momota

n. sp.

Circumvitellatrema momota  n. sp.

( Figs. 4–6View FIGURES 4 – 6)

Type host: Momotus momota (Linnaeus)  ( Coraciiformes  : Momotidae  ); the blue-crowned motmot.

Additional host: Likely in other birds being maintained at Zoos.

Type locality: Audubon Zoo in New Orleans, Louisiana, U.S.A. This is likely a species that was introduced from imported exotic birds; natural host unknown.

Site of infection: Lungs and air sacs of lungs.

Number of worms present: Approximately 80– 100 adult worms.

Deposited specimens: Holotype USNPC 101180.00; paratype (1 specimen) USNPC 101181.00; voucher specimen (2 specimens) HWML 48961, 48962.

Etymology: The species is named after the genus of the bird host, Momotus Brisson. 

Description: Based on 3 specimens. With characteristics of the genus. Body large, tapered anteriorly, 8.5 (7.4–10.5) mm long by 2.9 (2.4–3.6) mm wide at widest point. Oral sucker indistinct, 122 (110–135) long by 200 (170–220) wide. Acetabulum absent. Mouth slightly subterminal; prepharynx short, 105 (40–140) long; pharynx well developed, 297 (250–370) long by 333 (300–380) wide; esophagus 275 (220–350) long; ceca simple, long, uniting near posterior extremity to form cyclocoel. Ratio of oral sucker width to pharynx width 1: 1.7 (1: 1.5 – 1: 1.9). Testes generally smooth, usually spherical to subspherical, wider than long, arranged diagonally in posterior 1 / 3 of body in intercecal region; anterior testis 635 (530–800) long by 655 (630–690) wide; posterior testis 530 (435–610) long by 795 (700–890) wide. Posttesticular space 605 (470–860), approximately 7 % of body length. Cirrus sac (n= 1) 390 long by 210 wide. Genital pore postpharyngeal, on midline of body, opening at level of posterior 1 / 3 of pharynx on ventral surface of body. Ovary smooth, oval to round, situated intertesticularly forming triangle with testes, 465 (300–385) long by 335 (310–390) wide. Ratio of ovary width to average width of testes 1: 2.2 (1: 1.9–2.5). Uterine seminal receptacle present, located short distance posterodextral to ovary, approximately 270 (230–310) long by 260 (220–230) wide. Ootype immediately posterodextral to ovary. Laurer’s canal absent. Vitelline follicles (n= 30) round to laterally spherical, 30–100 wide, distributed along ceca from level of esophageal bifurcation to posterior extremity; vitelline fields confluent anteriorly and posteriorly forming continuous loop in body. Uterus extending from level of posterior testis anteriorly to level of pharynx with few uterine loops overreaching ceca laterally at level of testes, proximal end filled with sperm; 3–4 uterine loops invading intertesticular space, 1 invading space between ovary and posterior testis, none entering posttesticular space. Fully developed eggs in uterus of fixed specimens (n= 30) 121 (104–125) long by 62 (57–71) wide; eggs isolated from fecal samples without fixation larger than fixed eggs, 142 (137–146) long by 71 (68–74) wide; miracidia nonoculate, no miracidia free in uterus. Excretory vesicle Y to V-shaped. Excretory pore slightly subterminal, opening on dorsal surface of body.

Remarks. Circumvitellatrema momota  n. sp. represents the type and only species currently assigned to the new genus.


United States National Parasite Collection


Howard W. Manter Laboratory of Parasitology