Spirinia Gerlach, 1963

Leduc, Daniel & Verschelde, Dominick, 2015, New Spirinia and Stygodesmodora species (Nematoda, Spiriniinae) from the Southwest Pacific, and a revision of the related genera Spirinia, Chromaspirina and Perspiria, European Journal of Taxonomy 118, pp. 1-25 : 8-9

Genus Spirinia Gerlach, 1963

Type species

Spira parasitifera Bastian, 1865 .

Emended diagnosis

Robust body with rounded or conical head region and conical tail, fine body annulations. Annulated head region; body annulations normally completely surround the amphideal fovea, with few exceptions. Spiral amphideal fovea. Buccal cavity narrow, lightly cuticularised; no or small/inconspicuous dorsal tooth, no or minute subventral teeth. Pharynx with small pyriform, oval, or rounded posterior bulb without cuticularised lumen. Precloacal supplements usually absent. Short conical tail.

Valid species

Spirinia gerlachi ( Luc & De Coninck, 1959) . Main diagnostic characters: “Annulations beginning halfway down the lateral organ…long attenuated conical tail”; also clear in drawings ( Luc & De Coninck 1959: fig. 25). Despite the presence of an amphid only partially surrounded by cuticle annulations, this species is left within Spirinia because of the shape of the tail (conical), which is the primary trait for differentiating between Spirinia and Perspiria .

Spirinia gnaigeri Ott, 1977 . Amphids almost entirely located within the body annulations in one male, but only the posterior half of another male’s amphid is surrounded by body annulations (compare figs 42 and 43 in Ott 1977); however, as the species has a conical tail, it belongs within Spirinia .

S. guanabarensis ( Maria et al., 2009) comb. nov. (synonym: Chromaspirina guanabarensis Maria et al., 2009 ). Main diagnostic characters: “Buccal cavity large with an acute dorsal tooth and two smaller ventrosublateral teeth. ” However, later in the text it is stated that: “ Chromaspirina guanabarensis sp. nov. belongs to the group of species characterized by a poorly developed dorsal tooth.” Drawings also show a small buccal cavity with a small dorsal tooth and minute subventral teeth ( Maria et al. 2009: fig. 1). Tail is conical. This species is therefore transferred to Spirinia .

S. hopperi Coles, 1987 . Main diagnostic characters: “Cuticle without striations... small dorsal tooth is present in the narrow mouth cavity.” Drawings show a conical tail ( Coles 1987: fig. 3).

S. inaurita ( Wieser & Hopper, 1967) comb. nov. (synonym: Chromaspirina inaurita Wieser & Hopper, 1967 ). Main diagnostic characters: ‘‘Buccal cavity with three small teeth (these teeth are smaller than in most other species of Chromaspirina and stress the proximity of the genus to Spirinia ).’’; the drawings are inconclusive, but the description clearly describes small teeth. This species is therefore transferred to Spirinia .

S. laevioides Gerlach, 1963 . The drawing shows a small buccal cavity, a small dorsal tooth, and amphids located within the annulated head region ( Gerlach 1963: fig. 2).

S. laevis ( Bastian, 1865) (synonym: S. pilosa Allgén, 1935 ). The drawing shows small teeth, amphids located entirely within the annulated head region, and a short conical tail ( Bastian 1865: fig. 204).

S. okemwai ( Muthumbi et al., 1995) comb. nov. (synonym: Chromaspirina okemwai Muthumbi et al., 1995 ). We studied the type material, which shows that this species has a cylindrical pharynx with only a slightly swollen terminal bulb, whose shape cannot be described. The teeth are difficult to distinguish and hence cannot be called ‘large’ or ‘distinct’; therefore, we transfer this species to the genus Spirinia .

S. parasitifera ( Bastian, 1865) . Some descriptions of this species show the amphids being only partially surrounded by annulations ( Gerlach 1963; Vincx & Gourbault 1989), and others describe specimens with amphids entirely surrounded by annulations ( Coles 1987; Vincx & Gourbault 1989); furthermore, additional descriptions and drawings depict either a conical tail ( Gerlach 1963: fig. 1; Coles 1987: fig. 3) or a prolonged conical to long conical tail ( Wieser & Hopper 1967: fig. 17). Hence, until further examination and comparison of these different specimens can be done, we leave this species within Spirinia .

S. parma (Ott, 1972) comb. nov. (synonym: Chromaspirina parma Ott, 1972 ). Main diagnostic characters: “... stoma conical, with a small acute dorsal tooth and two minute ventral teeth…”; this species is therefore transferred to the genus Spirinia .

S. schneideri (Villot, 1875) . Luc & Deconinck (1959) describe this species with a smooth cuticle, and Coles (1987) describes it “without cuticular striations”. The SEM micrograph by Coles (1987: fig. 9a), however, shows striations surrounding the amphids. The tail is short and conical.

S. sophia Silva et al., 2009 . Main diagnostic characters: “Buccal cavity with one dorsal tooth and two minute, ventrosublateral teeth”; clear in drawings, which also show the amphid completely surrounded by cuticle annulations ( Silva et al. 2009: fig. 6). Tail conical.

Species inquirendae

Spirinia granulata (Allgén, 1929) comb. nov. (synonym: Spirina granulata Allgén, 1929 ). This species was described based on two juveniles only, with very poor drawings and inadequate descriptions. Hence, we have to regard this species as species inquirenda.

S. paucispira (Schuurmans Stekhoven, 1950) comb. nov. (synonym: Chromaspirina paucispira Schuurmans Stekhoven, 1950 ). This species was considered species inquirenda by Wieser & Hopper (1967) and Muthumbi et al. (1995), because the original description was based on a single female specimen. It was stated that the buccal cavity of this species has an “indication of a dorsal tooth”. Based on this character, which is sufficient to distinguish between Spirinia and Chromaspirina , this species is transferred to the genus Spirinia (but remains species inquirenda due to the incomplete nature of the original description).

S. similis (Cobb, 1898) (synonym: Spira similis Cobb, 1898 ). Considered invalid by Coles (1987) due to lack of illustrations.

S. tenuicauda (Allgén, 1959) (synonym: Spirina tenuicauda Allgén, 1959 ). This species has to be regarded as a species inquirenda, as the only description Allgén made was to write “differing from Sp. parasitifera ,” and his drawings are inadequate.