Paragonimus kerberti, Bayssade-Dufour & Chermette & Šundić & Radujković, 2015

Bayssade-Dufour, Christiane, Chermette, René, Šundić, Danijela & Radujković, Branko M., 2015, Paragonimus kerberti n. sp. (Digenea, Paragonimidae), parasite of carnivores in Cameroon, Ecologica Montenegrina 2 (3), pp. 271-277 : 274-276

Paragonimus kerberti n. sp. ( Figs. 2 A-B, 3)

Material studied: Adult worms from experimentally infected cats were studied. The type specimens were deposited in National History Museum of Paris , France .

Registration numbers: holotype 187 TM 1 ; paratype 187 TM 2 .

Etymology: The specific name Paragonimus kerberti was given in honour to Coenraad Kerbert, who described P. westermani , type species of the genus (in 1878).

First intermediate host (snail): unknown.

Second intermediate host (crustacean): Sudanonautes africanus (A. Milne-Edwards, 1869) .

Definitive hosts: Felis catus (experimental).

Site : lungs.

Type locality: Bikpwae , in South Province of Cameroon: 2°59’ N, 11°17’ E, altitude: 636 m. a.s.l. ( Fig. 1)

Other localities: Bulutu , Béchati and Mahollé , near Tombel in South- West province of Cameroon. Bulutu is settled at 4°38’25’’N, 9°26’21’’E; altitude 2457 m.a.s.l. Mahollé is settled at 4°44’47’’N, 9°40’13’’E; altitude 523 m. a.s.l. ( Fig. 1) .

Description of the adult worms

The adult worms originated from the lungs of final hosts, experimentally infected. New species is described after 3 adult ovigerous worms: 186 TM 1 , 187 TM 1 , 187 TM 2 . Measurements were done upon one young (85 days old) and one older (331 days old) specimen .

The bodies of these worms (from fixed, stained and mounted specimens, more or less flattened), measured 7,692 µm x 4,600 µm for young specimen, and 10,900 µm x 6,000 µm for the old one. Forebody 2,840 – 3,400 long; hindbody 4,840 –7,400 long. Ratio forebody/hindbody 0.58–0.46.

All present an elongate body, with spinous tegument. Oral sucker rounded, ventro-terminal, ventral sucker in the 1/3 of the body. Oral sucker 770–1,200. Ventral sucker rounded, 700–900. Ratio oral sucker/ventral sucker ( OS /VS) in adults: 1.10–1.33. Digestive apparatus with a mouth in oral sucker, pharynx well developed (384–800), oesophagus short, ondulating caeca large, reaching the hindbody. The genital apparatus with a lobed ovary, with 5-10 thick lobes, like a hand, opposite to uterus (1,307 x 846– 1,500 x 1,000). Uterus curled, drawing an 8 (visible in young specimen), the first curl crossing the metraterm, near the hermaphrodite pore (4,460 –5,400). Ovary and uterus pretesticular. Metraterm opening in hermaphrodite pore, immediately posterior to the acetabulum. Mehlis gland voluminous, median (540– 1,050). Vitellin system abundant, dendritic, extended in latero-dorsal fields of the body. Two transverse vitelloducts ending in a median rounded bag.

Two large, unequal, triangular testes, larger anteriorly than posteriorly, with 6-10 small rounded lobes, both in hindbody (left testes 2,150x 1,000 – 3,500 x2,000; right testes 1,770x 1,307 – 3,400 x2,500). Seminal vesicle falciform, 1,000 –1,600. Two spermiducts reaching the seminal vesicle under the acetabulum. The excretory bladder long, reaching the caecal bifurcation (6,460 –9,100).

Description of the metacercariae

Excysted living metacercariae measured 610-960 x 380-580 µm. They had a long excretory bladder, filled with dark granules, extending either between the two suckers, or close to the pharynx. The excretory pore was terminal. Suckers subequal; OS /VS ratio range from 0.75 to 1.15.

n. sp. (scale bar 100 µm).

Measurement of eggs

The metraterm eggs measure in length 98 µm, based on 20 specimens.

First living laid eggs measure 102 (85-115) x 60 (48-75) µm (20 specimens).

The duration of incubation (35 eggs monitored), at 22 °C, was 37 days, with a very long period of morula stage.

Prepatent period (period between infection with a parasite and appearance of eggs in feces) unknown, probably about 78-80 days. In cat 187 TM all the mated worms after 85 days were ovigerous.

Remarks

Paragonimus kerberti n.sp. is the fourth paragonimid species described from Africa. This species can be distinguished from other African paragonimids by four main characteristics:

— triangular testes, larger anteriorly than posteriorly, with small rounded lobes on the inner part,

— hand shape ovaries with 5-10 lobes,

— falciform seminal vesicle, posterior to the ventral sucker,

— utrerus in the form of “8”.