Cephalobellus magalhaesi (Schwenk, 1926)

Rusconi, José Matias, Achinelly, Maria Fernanda & Camino, Nora Beatriz, 2017, First record of Gryllophila skrjabini Sergiev, 1923 and Cephalobellus magalhaesi Schwenk, 1926 (Nematoda: Thelastomatidae) parasites of Neocurtilla claraziana Saussure, 1874 (Orthoptera: Gryllotalpidae) in Argentina, Papéis Avulsos de Zoologia (São Paulo) 57 (37), pp. 473-480 : 475-477

Cephalobellus magalhaesi (Schwenk, 1926)

Description

Morphology

Female: 5.5 to 6.4 mm long by 270 to 315 µm wide. Cuticle transversely striated up to the level of the oesophagus ( Figs. 2B and C ). Lips not salient. Buccal cavity about 7 µm deep. Oesophagus 569 µm long, consisting of an anterior cylindrical corpus, 432 µm long by 46 µm wide; an isthmus 36 µm long; and a posterior valvular bulb 102 µm in diameter. Intestine dilated anteriorly to form a cardia. Nerve ring 261 µm from the anterior end of body. Excretory pore posterior to base of oesophagus, 774 µm from the anterior extremity. Anus 270 µm from posterior end of body; tail short, attenuated conical ( Fig. 2F ). Vulva just behind the middle of body ( Fig. 2D ). Ovaries lying in the opposite direction to their corresponding uteri and reflexed near their terminations; uteri divergent. Eggs ellipsoidal, almost spherical ( Fig. 2E ), 57 µm long by 42 µm wide.

Morphometry

Female (n = 130): total length = 5862 ± 413.08 (5520-6456), cephalic diameter = 22.5 ± 5.19 (18-27), distance from anterior end to nerve ring = 261.4 ± 12.7 (252-270), width at level of nerve ring = 126 ± 12.7 (108-135), oesophagus length = 569.2 ± 11.3 (333-639), anterior distance to basal bulb = 469.3 ± 11.3 (458-485), distance from anterior end to excretory pore = 774 ± 7 (767-781), greatest width = 292.5 ± 21.4 (270-315), width at level of vulva = 272.2 ± 4.5 (270-279), vulval length = 29.2 ± 4.5 (27-36), vulval width = 11.2 ± 4.5 (9-18), V = 50.8% ± 3.4 (46.5%-55%), posterior end width = 195.7 ± 13.5 (189-216), tail length = 270 ± 5.7 (263-277), egg length = 57 ± 6.3 (54-63), egg width = 42 ± 6.3 (36-45).

Male: not found.

Host: nymphs and adults of the mole cricket Neocurtilla claraziana Saussure, 1874 .

Locality: Gorina (34°54’29”S; 58°02’25”W)

Site of infection: hindgut (last part of intestine).

Prevalence: 33%.

Figures

FIGURE 2: Cephalobellus magalhaesi. (A) Female, entire. (B) Cephalic region (SEM). (C) Cephalic region. (D) Vulva, lateral view. (E) Eggs. (F) Tail (SEM).