Pungentus marietani Altherr, 1950

Peña-Santiago, Reyes, Ciobanu, Marcel & Abolafia, Joaquin, 2013, Characterization of Iberian species of the genus Pungentus Thorne & Swanger, 1936 (Nematoda, Dorylaimida, Nordiidae), European Journal of Taxonomy 52, pp. 1-17 : 10-12

Pungentus marietani Altherr, 1950

Figs 1 I-K, 5

P. alpinus Vinciguerra & Giannetto, 1984: 49 , figs 1-3.

Diagnosis

This species is distinguishable by the length of its body (1.15-1.66 mm), the lip region being offset by a constriction and 11-15 μm wide, an odontostyle being 22-28 μm long and 1.9-2.3 times lip region width or 1.5-2.1% of total body length, neck length of 320-337 μm, a pharyngeal expansion 130-176 μm long or 39-43% of total neck length, a didelphic-amphidelphic female genital system, a uterus being tripartite and 56-68 µm long or 1.4-1.6 times the body diameter, V = 42-52, and the female tail being rounded conoid (19-26 μm, c = 52-74, c’ = 0.7-1.0).

Material examined

Five females from one location, in various states of preservation.

Morphometrics

See Table 1 .

Description

Female

Moderately slender to slender nematodes of medium size, 1.15-1.56 mm long. Habitus after fixation ventrally curved, especially in the posterior body region, C- or G-shaped. Body cylindrical, tapering towards the anterior end. Cuticle three-layered, especially perceptible at the tail, 1.5-2.5 μm thick in anterior region, 2.0-2.5 μm at mid-body and 4.0-5.0 μm on dorsal side of tail; outer layer with very fine transverse striation, intermediate layer thicker than the outer and inner layers. Lateral chord 5.5-7.0 µm wide or occupying 12-19% of mid-body diameter, very granular, but lacking any differentiation. Lateral pores comparatively coarse, in two rows at the margins of lateral chord; ventral pores well perceptible along entire body ( Fig. 1K ), apparently connecting with sub-epidermal gland bodies. Lip region offset by constriction, 2.4-2.5 times as wide as high and ca. one-third (28-35%) of body diameter at neck base. Lips moderately angular and separate; labial and cephalic papillae distinct, but not especially protruding above cephalic contour. Amphid fovea cup-shaped, opening at level of cephalic constriction, occupying 6.5 μm or about one-half (52%) of lip region diameter. Cheilostome almost cylindrical, its walls distinctly thick and sclerotized at the anterior half; perioral refractive dots or platelets very prominent. Odontostyle 10.0-12.5 times as long as wide, 1.8-2.3 times longer than lip region diameter or 1.5-2.1% of total body length; aperture 3.0-5.0 μm long or 14-19% of its length. Odontophore rodlike, almost equal (0.9-1.1 times) to odontostyle. Guiding ring double, located at 15-16 μm or 1.2-1.5 times the lip region diameter from anterior end. Pharynx enlarging gradually; basal expansion 5.7-7.1 times as long as wide and 2.9-3.7 times the corresponding body diameter long, occupying about twofifths (39-43%) of total neck length. Pharyngeal gland nuclei located as follows: DO = 52, DN = 56- 61, S 1 N 1 = 77, S 1 N 2 = 79, S 2 N = 87-90. Nerve ring at 120-128 μm from anterior end or 38% of total neck length. Cardia rounded conoid, 7-9 x 10-14 μm. Genital system didelphic-amphidelphic, with both branches well and equally developed, the anterior 169-182, the posterior 144-210 μm long. Ovaries 43- 162 μm long; oocytes first in two or more rows, then in one row. Oviduct 82-118 μm long, or 2.2-2.9 times the body diameter, consisting of a slender portion with prismatic cells and a moderately developed pars dilatata. Oviduct-uterus junction marked by a distinct sphincter. Uterus 56-68 µm long or 1.4-1.6 times the body diameter, apparently tripartite, i.e., consisting of a proximal section with thick walls and distinct lumen, an intermediate narrowing, and a spheroid pars dilatata uteri. Vagina extending inwards 18-22 μm or about one-half (44-59%) of body diameter; pars proximalis almost as long as wide, 13-18 x 12-16 μm, with convergent walls and enveloped by weak circular musculature; pars refringens not very distinct in the females examined, but two pieces might be present; pars distalis 5.5-7.0 μm long. Vulva a pre-equatorial, short transverse slit, which is preceded by a depression of body surface. Prerectum 2.9- 4.2, rectum 0.9-1.1 anal body diameters long. Tail short and rounded conoid, somewhat more straight ventrally. Caudal pores two pairs, subdorsal, at the anterior half of tail.

Male

Unknown.

Distribution

This species was collected from one location in the southern Iberian Peninsula: the province of Granada, Sierra Nevada National Park, near road to Veleta summit (37°7’ N - 3°32’ W), in association with Mediterranean brushwood Retama sphaerocarpa (Linnaeus, 1753) Boissier 1840 as dominant species.

Remarks

The specimens from the Iberian population of this species are nearly identical to those of the types as described by Altherr (1950a) as well as to the type material of P. alpinus Vinciguerra & Giannetto, 1984 , the latter regarded as a junior synonym by Ahmad et al. (2000). Some morphological features, for instance the nature of the cuticle and the female genital system, are more accurately described here.

Pungentus marietani is certainly another widely distributed species in Europe, where it has been reported from Germany ( Ahmad et al. 2000), Italy ( Vinciguerra & Giannetto 1984, as P. alpinus ), Poland ( Brzeski 1963; Wasilewska 1967; Winiszewska-Slipinska 1987a, b, but see comments below), Switzerland ( Altherr 1950a) and the Netherlands ( Bongers 1988, as P. alpinus ). Besides, Vinciguerra (2006) mentioned its occurrence in Serbia, Slovakia, Macedonia and Canada. The true identity of the specimens studied by Winiszewska-Slipinska (1987a) remains uncertain, because of their larger general size: body 1.5-1.9 mm long (n=27) and odontostyle 28-31 µm; this material probably belongs to another species.

Figures

Fig. 1. Iberian Pungentus species. – A-C. Pungentus clavatus Ahmad & Jairajpuri, 1979. – D-H. Pungentus engadinensis (Altherr, 1950). – I-K. Pungentus marietani Altherr, 1950. – L-N. Pungentus silvestris Coomans & Geraert, 1962. – A, D, I, L. ♀, anterior region in lateral median view. B, E, J, M. ♀, genital system. C, G, K, N. ♀, posterior body region. F. ♂, posterior body region. H. ♀, caudal region.