Procamallanus (Spirocamallanus) bothi, Moravec & Justine, 2019

Moravec, František & Justine, Jean-Lou, 2019, New species and new records of camallanid nematodes (Nematoda, Camallanidae) from marine fishes and sea snakes in New Caledonia, Parasite (Paris, France) 26 (66), pp. 1-25 : 5-8

Procamallanus (Spirocamallanus) bothi n. sp.

Figures 3 , 4

urn:lsid:zoobank.org:act:CCA32AF1-B9B7-4A1C-99FF-2C5A5A53410B

Type host: Leopard flounder Bothus pantherinus (Rüppell) ( Bothidae , Pleuronectiformes ).

Site of infection: Intestine.

Type locality: Fishmarket , Nouméa, New Caledonia (collected 11 February 2011) .

Prevalence, intensity and details about fish: 1 fish infected/ 1 fish examined; 12 nematodes. The infected fish (Fish number: JNC 3310) was 234 mm in fork length and 128 g in weight.

Deposition of type specimens: Muséum National d’ Histoire Naturelle, Paris, France (male holotype, female allotype and eight paratypes, MNHN JNC 3310 ); Helminthological Collection, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences , České Budějovice , Czech Republic (two paratypes mounted on SEM stub, N–1201) .

Etymology: The specific name of this nematode relates to the genitive form of the generic name of the host.

Description

General: Medium-sized nematode with finely transversely striated cuticle. Mouth aperture oval, surrounded by 12 submedian cephalic papillae arranged in three circles, each formed by four papillae; papillae of outer circle larger; each of four small inner papillae present near margin of oral aperture accompanied by distinct proximal pore; pair of small lateral amphids present ( Figs. 3D , 4A, 4B and 4E ). Buccal capsule orange, thick-walled, longer than wide, with simple, well-developed basal ring. Maximum width/length ratio of buccal capsule 1:1.03–1.30. Inner surface of capsule provided with 13–19 spiral ridges in lateral view, 3–8 of them being incomplete ( Figs. 3B and 3C ). Muscular oesophagus shorter than glandular oesophagus; both parts of oesophagus slightly expanded near their posterior ends ( Fig. 3A ). Intestine brown, narrow. Deirids small, simple, with rounded end situated approximately at mid-way between base of buccal capsule and nerve ring ( Figs. 3A, 3B, 3E and 4D ). Excretory pore located short distance posterior to posterior end of muscular oesophagus ( Fig. 3A ).

Male (two specimens; holotype; measurements of paratype in parentheses): Length of body 18.20 (19.18) mm, maximum width 272 (367). Buccal capsule including basal ring 90 (90) long, its width 69 (72); basal ring 9 (9) long and 48 (51) wide. Maximum width/length ratio of buccal capsule 1:1.30 (1:1.25). Spiral ridges 14 (14), 6 (5) of which incomplete. Length of muscular oesophagus 476 (490), maximum width 102 (111); length of glandular oesophagus 612 (748), maximum width 123 (156); length ratio of muscular and glandular oesophagus 1:1.29 (1:1.53). Length of entire oesophagus and buccal capsule representing 6 (7)% of body length. Deirids, nerve ring and excretory pore 201 (195), 313 (313) and 639 (680) from anterior extremity, respectively. Posterior end of body ventrally bent, provided with wide, vesiculated caudal alae supported by pedunculate papillae; anteriorly alae interconnected by mound, forming a kind of pseudosucker, and posteriorly reaching to caudal terminal spines ( Figs. 3F, 3I , 4F and 4G ). Preanal papillae: three pairs of subventral pedunculate papillae, of which second and third pairs closer to each other than first and second pairs; postanal papillae: six pairs of pedunculate papillae, four subventral and two lateral (last pair representing phasmids); additional two pairs of small, transversely-elongate sessile ventral papillae surrounding cloacal opening ( Figs. 3F, 3I and 4G ). Spicules unequal, with sharply pointed distal ends; large (right) spicule 267 (270) long; small (left) spicule less sclerotized, 180 (177) long ( Fig. 3I ). Length ratio of spicules 1:1.48 (1:1.53). Gubernaculum absent. Tail conical, 207 (153) long, with two (dorsal and ventral) small terminal cuticular spines 6 (6) long ( Figs. 3F, 3I and 4H ).

Female (seven larvigerous specimens; measurements of allotype in parentheses. Measurements of additional three ovigerous specimens in brackets): Length of body 25.64–38.80 (37.92) [15.16–22.77] mm, maximum width 490–762 (734) [299– 408]. Buccal capsule including basal ring 102–114 (102) [96–105] long and 84–105 (90) [84–99] wide; basal ring 9–12 (9) [ 9] long and 60–66 (60) [57–69] wide. Maximum width/ length ratio of buccal capsule 1:1.06–1.27 (1:1.13) [1:1.03– 1.25]. Number of spiral ridges 12–18 (18) [ 12 – 19], of which 3–5 (5) [ 3 – 8] incomplete. Length of muscular oesophagus 571–639 (598) [530–571], maximum width 129–136 (136) [69–111]; length of glandular oesophagus 721–911 (911) [612–748], maximum width 135–177 (177) [102–135]; length ratio of muscular and glandular oesophagus 1:1.22–1.52 (1:1.52) [1:1.15–1.38]. Length of entire oesophagus and buccal capsule representing 4–6 (4) [ 7 – 9]% of body length. Deirids, nerve ring and excretory pore 231–258 (233) [218–231], 340–381 (381) [313–354] and 707–884 (707) [639–680], respectively, from anterior extremity. Vulva mostly pre-equatorial (exceptionally equatorial), 11.37–18.90 (18.90) [7.71–10.36] mm from anterior extremity, at 36–50 (50) [ 46 –50]% of body length. Vulval lips not elevated. Vagina directed posteriorly from vulva. Uterus filled with numerous larvae 390–404 long and 21–24 in maximum width, with slender tail [with small amount of eggs]. Tail broad, rounded, its posterior end abruptly narrowed to form digit-like protrusion provided with 2 (2) [ 2], dorsal and ventral, small terminal cuticular spikes; length of entire tail 190–218 (204) [138–204]; digit-like protrusion 36–51 (39) [ 21 – 42] long, 15–18) [ 12 – 15] wide, length of spines 3–5 (5) [ 5] ( Figs. 3G, 3H , 4C and 4I ).

Remarks

Nematodes of the present material belong to the morphological group of Procamallanus (Spirocamallanus) species characterized by the presence of wide caudal alae, three pairs of pedunculate preanal papillae, two unequal spicules and two caudal spikes on a digital projection in the female. According to Yooyen et al. [ 46], in the Indo-Pacific region this group contains 23 nominal species reported mostly from marine fishes. However, the great majority of them are poorly described and should be considered species inquirendae [see also 31, 40].

The following nine species of this morphological group from the Indo-Pacific region can be considered valid: P. (S.) anguillae Moravec, Taraschewski, Thairungroj Anantaphruti, Maipanich et Laoprasert, 2006 from Anguilla bicolor McClelland ( Anguillidae ) in Thailand and India [ 30, 31], P. (S.) gobiomori Moravec, Salgado-Maldonado et Caspeta-Mandujano, 2000 from freshwater Eleotridae in western Mexico [ 29], P. (S.) guttatusi (Andrade-Salas, Pineda-López et García-Magaña, 1994) from Siganus guttatus (Bloch) ( Siganidae ) off the Philippines [ 17, 22], P. (S.) istiblenni (Noble, 1966) from Istiblennius zebra (Vailland et Sauvage) ( Blenniidae ) off Hawaii [ 33, 40], P. (S.) monotaxis (Olsen, 1952) from Lethrinidae off Hawaii, New Caledonia and French Polynesia [ 25, 35, 39], P. (S.) pereirai (Annereaux, 1946) from Atherinopsis californiensis Girard ( Atherinidae ) off California, USA [ 3], P. (S.) rigbyi Yooyen, Moravec et Wongsawad, 2011 from Otolithes ruber (Bloch et Schneider) ( Sciaenidae ) off Thailand [ 46], P. (S.) similis Yooyen, Moravec et Wongsawad, 2011 from Sillago sihama (Forsskål) ( Sillaginidae ) off Thailand [ 46] and P. (S.) variolae Moravec, Justine et Rigby, 2006 from Variola spp. ( Serranidae ) off New Caledonia [ 27].

Of these, as compared with the new species, the right spicule is distinctly longer in P. gobiomori (318–348 µm vs 267–270 µm), P. pereirai (430 µm), P. rigbyi (315–360 µm), P. similis (435–492 µm) and P. variolae (327–357 µm); moreover, the spiral ridges in the buccal capsule are less numerous in P. gobiomori (8–10 vs 13–19), P. similis (10–12) and P. variolae (11–12) and all these five species also differ in the family and order of their fish hosts ( Perciformes : Eleotridae , Serranidae , Sciaenidae and Sillaginidae or Atheriniformes : Atherinidae vs Pleuronectiformes : Bothidae ). The right spicule of P. anguillae is somewhat longer (289–384 µm vs 267–270 µm) than that of P. bothi n. sp., the spiral ridges are usually less numerous (10–15 vs 13–19) and both species differ in the type of the host (freshwater eel vs marine flatfish). The length of the right spicule in P. istiblenni and P. monotaxis is rather similar to that in the new species (263–302 µm and 279–315 µm, respectively vs 267–270 µm), but the spiral ridges are mostly less numerous (12–15 and 10–17, respectively vs 13–19); deirids of P. istiblenni are located in 2/3 of the distance between the base of the buccal capsule and the nerve ring (vs in the mid-length of this distance) and the excretory pore at the level of the posterior end of the muscular oesophagus (vs somewhat posterior to this level), and the female tail of P. istiblenni is more conical as compared with that of P. bothi n. sp.; the excretory pore of P. monotaxis is located short distance anterior to the posterior margin of the muscular oesophagus (vs somewhat posterior to the anterior end of the glandular oesophagus). Moreover, the hosts of P. istiblenni and P. monotaxis belong to different fish families and orders ( Perciformes : Blenniidae and Lethrinidae , respectively vs Pleuronectiformes : Bothidae ).

Figures

Figure 3. Procamallanus (Spirocamallanus) bothi n. sp. from Bothus pantherinus. (A, B) Anterior end of male, lateral and dorsoventral views, respectively; (C, D) cephalic end of male, lateral and apical views, respectively; (E) deirid; (F) tail of male, lateral view; (G) tail tip of female, lateral view; (H) tail of female, lateral view; (I) posterior end of male, lateral view.

Figure 4. Procamallanus (Spirocamallanus) bothi n. sp., scanning electron micrographs. (A, B) Cephalic end, lateral and apical views, respectively; (C) female tail, sublateral view; (D) deirid; (E) region of amphid, apical view (arrow indicates lateral pore on margin of oral aperture); (F) posterior end of male, subventral view; (G) tail of male, ventrolateral view (arrows indicate pedunculated caudal papillae); (H) tail tip of male (lateral view); (I) tail tip of female, sublateral view). (a) amphid; (b) cephalic papilla of external circle; (c) cephalic papilla of middle circle; (d) cephalic papilla of internal circle; (e) anus; (f) cloacal aperture; (g) margin of oral aperture; (p) phasmid.