Janinellia peebeehi, Mariaux, Jean & Georgiev, Boyko B., 2018

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 : 3

Janinellia peebeehi sp. n. Figures 1-5

Host:

Elaenia chilensis Hellmayr, 1927 ( Passeriformes , Tyrannidae ), Fio-fio, Chilean White-crested Elaenia .

Prevalence:

2/12 (16.7%).

Intensity:

1-2.

Site of infection:

Small intestine.

Locality:

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

Date:

29.11.2008 and 2.12.2008.

Specimens studied:

3 specimens. Holotype: MHNG-PLAT-82292 (on slide). Paratypes: MHNG-PLAT-120515; MHNG-PLAT-82293 (2 specimens, on slides).

Hologenophore (genseq-2 COI):

MHNG-PLAT-82292 [CHIL-002/C2] and MHNG-PLAT-120515 [CHIL-038/C2]. Partial COI sequence, Genbank MH663460 and MH663461.

Etymology.

The species name phonetically reminds one of the acronyms of the NSF program that was sponsoring the project (Planet Biodiversity Inventory, PBI).

Description.

Body of small to medium size, up to 34 mm long (inferred from fragmented specimen). Strobila with almost parallel margins, gradually expanding in posterior direction: immature, mature, pregravid and gravid proglottides up to 250, 550, 700 and 1025 wide, respectively. Maximum width achieved at level of early gravid proglottides. Most complete specimens consisting of up to 157 proglottides. Proglottides weakly craspedote, wider than long except for very last gravid ones, which can be up to twice longer than wide. Two pairs of osmoregulatory canals. Ventral canals up to 50 in diameter, with posterior transverse anastomosis in each proglottis. Dorsal ones up to 11 in diameter.

Scolex (Fig. 1) not clearly separated from neck, 210-295 (258, n = 3) wide at middle of suckers; anterior part of scolex conically tapering; apex may form pipette-like protrusion. Suckers weakly muscular, oval 110-137 × 82-105 (120 × 96, n = 12). Apical apparatus consisting of oval rostellar pouch, 127-142 × 65-75, thin-walled, densely filled with glandular tissue, reaching to level of middle to posterior half of suckers. No rostellum. Neck straight, 225-325 wide. Genital ducts passing between osmoregulatory canals. Genital pores at border of first third of lateral proglottis margin, often forming genital papilla, irregularly alternating. Genital atrium simple, inconspicuous, thin-walled, tubular, with infundibular orifice.

Testes 13-17 (14.8, n = 25) in number, disposed in two dense layers, forming a continuous field filling most of posterior two thirds of median field of proglottides; posterior, lateral and dorsal to vitellarium, overlapping posterior parts of ovary; in younger proglottides, testes may occupy most of dorsal parenchyma (Fig. 2); testes 75-100 (89, n = 15) in diameter. External vas deferens very developed, forming multiple coils at extremity of cirrus-sac, filling the antero-poral and central part of median field. Cirrus-sac 130-182 × 25-38 (157 × 32, n = 30), oblique, straight, thin-walled, reaching or crossing poral osmoregulatory canals. Internal vas deferens coiled, making several loops in proximal half of cirrus-sac (Fig. 3). Evaginated cirrus short (up to 44 long), almost cylindrical, thin, 8-9 in diameter at its basal part, slightly tapering distally; unarmed.

Vitellarium large, up to 130 wide, central, lobate, oval or bean-shaped. Ovary transversely-elongate, massive and multilobulate, with two poorly marked and slightly asymmetrical wings, occupying entire width of median field and up to 30-40% of proglottis length. Mehlis’ gland not distinct as glandular structure. Ootype central, just anterior to vitellarium. Seminal receptacle oval 45-58 × 35-45 when empty, up to 150 × 87 when full. Vagina posterior to cirrus-sac, straight, distally thin-walled, proximally bordered with a row of large, dense cells; distal part often dilated, sometimes filled with spermatozoa (Figs 2, 3).

Uterus initially as loose reticulated network, then becoming denser as eggs develop, overlapping osmoregulatory canals and filling most of proglottis, including part of lateral fields (Fig. 4). Embryophore thick, 37-42 × 30-38 (39.5 × 34.5, n = 25). Oncosphere 27-30 × 22-27 (28.5 × 24, n = 25). Embryonic hooks sub-equal: central pair 13-15 (14, n = 10) long, lateral pairs 13-15 (13.5, n = 12) long (Fig. 5).

Remarks.

The new species is the type species of the newly erected monotypic genus Janinellia gen. n.