PTERYGODERMATITES ( MESOPECTINES ) SENEGALENSIS N. SP. (NEMATODA, RICTULARIIDAE), A PARASITE OF MASTOMYS HUBERTI (RODENTIA, MURIDAE) IN SENEGAL

J. Parasitol., 86(6), 2000, p. 1313–1317 q American Society of Parasitologists 2000

PTERYGODERMATITES (MESOPECTINES) SENEGALENSIS N. SP. (NEMATODA, RICTULARIIDAE), A PARASITE OF MASTOMYS HUBERTI (RODENTIA, MURIDAE) IN SENEGAL Malick Diouf, Cheikh Tidiane Baˆ, and Bernard Marchand* Laboratory of Parasitology, Department of Animal Biology, Faculty of Sciences, Cheikh Anta Diop University, Dakar, Senegal ABSTRACT: Pterygodermatites (Mesopectines) senegalensis n. sp. (Nematoda: Rictulariidae) is described from Mastomys huberti in Senegal. It differs from other species of the subgenus by the morphology of the head, which exhibits 4 simple cephalic papillae and a nearly axial buccal opening, the length of the spicules, the number of precloacal cuticular formations, and the absence of cephalic apophyses.

Species of Pterygodermatites Wedl, 1861 are intestinal nematodes of mammals and belong to 5 subgenera (Quentin, 1969). To our knowledge, only P. (Mesopectines) taterilli (Baylis, 1928), P. (Mesopectines) harrisi (Baylis, 1934), P. (Neopaucipectines) desportesi (Chabaud and Rousselot, 1956), and P. (Mesopectines) ortleppi Quentin, 1969 have been described from African rodents (Vassiliades, 1992). In the present work, we describe a new species of Pterygodermatites and report its occurrence in Mastomys huberti (Rodentia, Muridae). MATERIALS AND METHODS Nematodes were collected live from the duodenum of 25 M. huberti. For light microscopy, worms were fixed in hot 70% ethanol and cleared with lactophenol (1 g crystallized phenic acid, 1 ml lactic acid, 2 ml glycerine, 1 ml distilled water). For scanning electron microscopy, worms were dehydrated with ethanol, critical point dried, mounted on metal stubs, coated with a gold film by sputtering, and examined with a Jeol JSM 35 CF scanning electron microscope. Morphological studies were carried out using 8 males and 10 females. Measurements are those for types followed in parentheses by the range for the paratypes. Type material is deposited in the Museum National d’Histoire Naturelle de Paris (MNHN).

DESCRIPTION

like cuticular armaments. Most posterior pair of cuticular armaments 460 (380–600) mm from posterior body extremity. Female allotype: Length 26 (24–28) mm, width 890 (850–900) mm. Nerve ring, excretory pore, and deirids 240 (200–300), 300 (240–360), 1,600 (1,150–1,650) mm from cephalic extremity, respectively. Esophagus 3,250 (3,000–3,500) mm long with muscular region 1,000 (950– 1,200) mm long. Vulva between 2 rows of cuticular armaments at 2.6 (2.5–2.8) mm from cephalic extremity (Fig. 12). Prevulvar spines 42 (40–43) pairs. Ninety-one (90–94) total pairs of platelike and spinelike cuticular armaments. Level of transition from plate and spines at 480 (400–520) mm from vulvar opening. Most posterior pair of cuticular armaments at 11,300 (9,200–12,800) mm from posterior body extremity. Uterus didelphic, with branches posterior to vulva. Ovejector 1.84 (1.75–1.90) mm long. Embryonated eggs ovoid, 38 (38–40) mm long by 26 (25–30) mm wide (Fig. 3). Tail 440 (400–450) mm long (Fig. 6). Taxonomic summary Type host: Mastomys huberti Wroughton, 1908 (Rodentia, Muridae). Site of infection: Duodenum. Type locality: Richard-Toll (North of Senegal) (168709N, 158809W). Specimens deposited: MNHN 246 HF holotype, allotype and 16 paratypes (7 males and 9 females). TABLE I. Comparative morphometric data for Prerygodermaitites (Mesopectines) senegalensis n. sp and the 2 closest species of the genus and of the subgenus from African rodents.

Pterygodermatites (Mesopectines) senegalensis n. sp. (Figs 1–14) General: Nematodes yellowish after fixation. In both sexes, cephalic extremity with 4 simple cephalic papillae, 2 submedian amphids, 6 labial papillae in depressions (4 lateroventral, 2 laterodorsal), and circular oral opening with 29 (26–29) denticles (Fig. 7). Buccal capsule nearly axial with 1 dorsal and 2 ventral pharyngeal teeth. Dorsal tooth 14 (8– 16) mm long, more developed than ventral teeth (Figs. 1, 2, 7). Cephalic apophyses absent. Two lateroventral rows of spinelike cuticular armaments along body (Figs. 8, 10, 11). Esophagus strongyliform with short muscular part and long glandular posterior part. Excretory pore, deirids posterior to nerve ring (Fig. 1). Transverse cuticular striations more or less regular (Fig. 9). Male holotype: Length 9.65 (8.9–11.5) mm, width 620 (570–700) mm. Nerve ring, excretory pore, deirids 220 (210–250), 320 (310–350), 630 (570–700) mm from cephalic extremity, respectively. Esophagus 2.530 (2.400–2.800) mm long, with muscular part 540 (400–800) mm long. In posterior extremity, 1 precloacal cuticular formation 115 (110– 120) mm long present in the form of many associated tegumentary folds before the first pair of caudal papillae (Fig. 10). Eight pairs of caudal papillae (2 precloacal, 3 adcloacal, 3 postcloacal) (Figs. 5, 13, 14). Chitinized spicules equal and 100 (96–120) mm long (Fig. 4). Gubernaculum 30 (20–32) mm long (Fig. 4). Seventy (69–72) pairs of plateReceived 30 August 1999; revised 13 June 2000; accepted 13 June 2000. * Laboratoire Parasites et Ecosyste`mes me´diterrane´ens, Faculte´ des Sciences, Universite´ de Corse, B.P. 52, 20250 Corte, France.

Characteristics

P. (M.) taterilli (Baylis, 1928)

P. (M.) ortleppi Quentin, 1969

P. (M.) senegalensis n. sp. present work

Male length (mm)

3.6

5.5

Female length (mm) Number of cephalic papillae Number of precloacal cuticular formations Spicule length (mm)

34

8.4

9.65 (8.9– 11.5) 26 (24–28)

8

8

4

4 Unequal, 110/40 Dorsal

3 Equal, 67

1 Equal, 100

Dorsal

Nearly axial

6 Not reported

6 Not reported

6

63

75

70 (69–72)

64–74

91

91 (90–94)

Buccal opening Number of peribuccal papillae Dorsal esophageal tooth length (mm) Number of cuticular armaments in male Number of cuticular armaments in female

1313

14 (8–16)

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FIGURES 1–6. Pterygodermatites senegalensis n. sp. from Mastomys huberti. 1. Male, anterior extremity, left lateral view. Scale bar 5 60 mm. 2. Male, anterior extremity, left laterodorsal view. Scale bar 5 40 mm. 3. Embryonated egg. Scale bar 5 24 mm. 4. Spicule, lateral view. Scale bar 5 24 mm. 5. Male, posterior extremity, ventral view. Scale bar 5 240 mm. 6. Female, posterior extremity, lateral view. Scale bar 5 240 mm.

DIOUF ET AL.—NEW PTERYGODERMATITES FROM MASTOMYS HUBERTI

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FIGURES 7–11. Pterygodermatites senegalensis n. sp. 7. Female, head, apical view showing labial papillae (arrow), cephalic papillae (arrowhead). Am, amphid; D, denticles; Pt, pharyngeal tooth. Scale bar 5 40 mm. 8. Male, anterior extremity, ventral view showing 2 rows of armaments (arrows). Ep, excretory pore. Scale bar 5 50 mm. 9. Cuticle. Scale bar 5 20 mm. 10. Male, precloacal cuticular formation (arrow), lateral view. Scale bar 5 40 mm. 11. Female, posterior extremity showing a cuticular spine (arrow). Scale bar 5 2 mm. Etymology: The specific name of this species relates to its country of origin. Remarks The nematodes of the subgenus Mesopectines Quentin, 1969 are parasites of rodents (Gerbillidae, Muridae), carnivores (Viveridae), and primates in both Africa and Asia (Quentin, 1969). They have a buccal opening apical in position or displaced somewhat dorsally but never totally dorsal, 3 esophageal teeth, 1 crown of regular peribuccal denti-

cles, 37–51 pairs of prevulval spines, and 2 subventral rows of caudal papillae (Chabaud, 1975; Tkach and Swiderski, 1996). Our material conforms with this definition. To date, 16 species have been described in the subgenus Mesopectines (Quentin, 1969). Among these, only P. (M.) taterilli (Baylis, 1928) and P. (M.) orteleppi Quentin, 1969 resemble our material with respect to the number of peribuccal papillae, esophageal teeth, and prevulval spines. However, our material differs from previous species in body length, the morphology of the head (with 4 simple cephalic papillae), the number of

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FIGURES 12–14. Pterygodermatites senegalensis n. sp. 12. Female, vulvar opening, ventral view. Scale bar 5 2 mm. 13. Male, posterior extremity with 3 caudal papillae (arrowheads), lateral view. Scale bar 5 10 mm. 14. Male, posterior extremity with 5 caudal papillae (arrowheads), lateral view showing a spicule (arrow). Scale bar 5 10 mm. the precloacal cuticular formations, the number of the cuticular armaments, and the length of the spicules (Table I). Moreover, our specimens do not have cephalic apophyses or a dorsal buccal opening.

LITERATURE CITED BAYLIS, H. A. 1928. On a collection of nematodes from Nigerian mammals (chiefly rodents). Parasitology 20: 280–301.

. 1934. On a collection of cestodes and nematodes from small mammals in Tanganyika territory. Annals and Magazine of Natural History 10: 338–353. CHABAUD, A. G. 1975. Keys to genera of the order Spirurida. Part 1. Camallanoidea, Dracunculoidea, Gnathostomatoidea, Physalopteroidea, Rictularioidea and Thelazioidea. In CIH keys to the nematodes parasites of vertebrates, R. C. Anderson, A. G. Chabaud, and S. Willmott (eds.). Headley Brothers, Farnham Royal, U.K., p. 1–27.

DIOUF ET AL.—NEW PTERYGODERMATITES FROM MASTOMYS HUBERTI

, AND R. ROUSSELOT. 1956. Deux nouveaux Rictularia (Nematoda, Thelaziidae) d’Afrique Equatoriale. Annales de Parasitologie Humaine et Compare´e 31: 255–265. QUENTIN, J. C. 1969. Essai de classification des ne´matodes rictulaires. Me´moires du Museum National d’Histoire Naturelle de Paris 56: 57–115.

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TKACH, V. V., AND Z. SWIDERSKI. 1996. Scanning electron microscopy of the rare nematode species Pterygodermatites bovieri (Nematoda: Rictulariidae) a parasite of bats. Folia Parasitologica 43: 301–304. VASSILIADES, G. 1992. Inventaire des helminthes des verte´bre´s du Se´ne´gal. Revue Se´ne´galaise de Recherches Agricoles et Halieutiques 4: 72–83.