Kintneria (?) sp.

Mariaux, Jean & Georgiev, Boyko B., 2018, Bird cestodes from Huinay (Comau Fjord), Chilean Patagonia: several species of the family Dilepididae (Platyhelminthes, Cyclophyllidea), with the erection of two new genera, ZooKeys 797, pp. 1-18 : 9-11

Kintneria (?) sp. Figures 12-14

Host:

Xolmis pyrope (Gmelin, 1789) ( Passeriformes , Tyrannidae ), Diucon, Fire-eyed Diucon.

Prevalence:

1/1.

Intensity:

3 specimens.

Site of infection:

Small intestine.

Locality:

HSFS, Comau Fjord, Los Lagos region, Chile, −42.39, −72.42. Altitude 10-30 m.

Date:

1.12.2008.

Specimens studied:

MHNG-PLAT-87930.

Hologenophore (genseq-2 COI):

MHNG-PLAT-87930 [CHIL-028/C2]. Partial COI sequence, Genbank MH663465.

Partial description

(based on only a few available mature proglottides): Body of small size, largest specimen 12.8 mm long and maximum width 675 mm wide. Up to 86 proglottides observed (up to mature stage, no complete specimens available), wider than long, craspedote. Scolex 275-330 (n = 2) in diameter, bearing four elongated and rather weak unarmed suckers155-175 (164, n = 7) in diameter. Rostellar pouch 280-285 × 123-148 (n = 2) with dense posterior glandular zone. Rostellum large, 243-265 × 95-118 (n = 2) present, strongly muscular but with distinct central glandular zone (Fig. 12). Rostellar hooks 17-18 (n = 2) in number, in one row, 41-47 long (44.5, n = 17), with long handle (Fig. 13). Neck well marked 162-250 (206, n = 3) wide. Formation of proglottides distinct at 242-312 (277, n = 3) from posterior margin of suckers. Genital pores situated in first third of length of lateral proglottis margin, alternating irregularly in small series (i.e. 3, 2, 1, 3), up to 6 consecutive pores on same side observed. Ventral osmoregulatory canals connected posteriorly in each proglottis by transverse anastomosis. Genital ducts passing between osmoregulatory canals.

Testes 16-21 (18, n = 10) in number, situated in single posterior field, in 2-3 layers, not extending beyond osmoregulatory canals. External vas deferens coiled, forming compact aggregation. Cirrus sac thin-walled 139-168 × 30-36 (149 × 33, n = 7) extending past the osmoregulatory canals. Cirrus armed with very fine spines.

Vitellarium immediately anterior to testes field, central, slightly V-shaped. Ovary lobulated and elongate transversely, anterior (poorly visible in our material). Vagina in same plane as, and posterior to, cirrus sac; wide, straight, opening in simple genital atrium about 15 deep (Fig. 14). No gravid proglottides and no early uterine development visible.

Remarks.

This material is likely to represent a new species. However a complete description is not possible without observations of the uterine development. Its generic position remains uncertain. According to Bona’s (1994) keys, it could belong to one of two very similar genera: Monosertum Bona, 1994 or Kintneria Spaskii, 1968, both parasitic in passerine birds. These genera differ from one another essentially by the structure of their uterus, with or without capsules, a character, which we cannot determine in the present material due to the lack of gravid proglottides. A few other diagnostic characters are given by Bona (1994). Among them, the small size of the body of our specimens rather resembles Monosertum ; however, this character can often vary among species in many dilepidid genera. On the other hand, it corresponds to the diagnosis of Kintneria because of its larger rostellar hooks, the ovary that doesn’t reach the anterior proglottis margin and its cirrus armament consisting of short spines. For these reasons, we consider that it most likely belongs to the genus Kintneria . This genus was erected by Spasskii (1968) for a parasite of introduced European sparrows Passer domesticus (L.) in North America. The type species of this genus was identified as Choanotaenia passerina (Fuhrmann, 1908) by Kintner (1938). Spasskii (1968) considered it a distinct species, differing from the Palaearctic Monopylidium passerinum (Fuhrmann, 1908); he also placed it in the newly erected subgenus Kintneria Spasskii, 1968 within the genus Monopylidium as M. (Kintneria) capsulata Spasskii, 1968. Bona (1994) eventually elevated Kintneria to the generic rank and its validity was accepted by Mariaux et al. (2017). Kintneria is known from the Nearctic and members of Xolmis are restricted to the Neotropics; however, other tyrant-flycatchers are known to migrate between North and South America, suggesting that genera of avian cestodes may have rather Pan-American than restricted distributions. This is the first cestode ever reported from the genus Xolmis .

To our knowledge the genus is monotypic and K. capsulata can easily be separated from our material by its shorter rostellar hooks and longer cirrus sac. Thus, should the observation of gravid segments confirm the placement of the present material into Kintneria , it would belong to a new species.

The two species belonging to the other similar genus, Monosertum parinum (Dujardin, 1845) and M. mariae (Mettrick, 1958), are known from European passerine birds only; furthermore, they are characterized by an osmoregulatory system forming a complicated reticular formation in the scolex and the neck ( Komisarovas and Georgiev 2007). Such complicated network of osmoregulatory canals has not been observed in the present material.