Ceratothoa capri (Trilles, 1964)

Hadfield, Kerry A., Bruce, Niel L. & Smit, Nico J., 2016, Redescription of poorly known species of Ceratothoa Dana, 1852 (Crustacea, Isopoda, Cymothoidae), based on original type material, ZooKeys 592, pp. 39-91 : 43-45

Taxon classification Animalia Isopoda Cymothoidae

Ceratothoa capri (Trilles, 1964) Figure 2

Meinertia capri Trilles, 1964a: 188-198, figs 1-41; 1972a: 1218-1220, figs 219-263, pl. II (17), pl. III (22); 1972b: 1256.- Trilles and Raibaut 1973: 277.

Ceratothoa capri .- Trilles 1986: 623, tab. 1; 1994: 116.- Horton 2000: 1045-1046, figs 5 ( c–e).- Rodríguez-Sánchez, Serna and Junoy 2001: 154.- Junoy and Castello 2003: 307.- Kirkim, Kocataş, Katağan and Sezgin 2008: 382-385.- Kirkim, Ozcan and Katagan 2009: 1079-1085, figs 2B & 3 B–E.- Innal and Kirkim 2012: A13-A16, figs 1 A–B.- Al-Zubaidy and Mhaisen 2013: 166-172, fig. 5.

Material examined.

Lectotype [here designated]. National Museum of Natural History, Paris (MNHN-IU-2014-17477) - female (16 mm TL, 8 mm W) collected in buccal cavity of Capros aper off coast of Nouvelle (Aude, France, Mediterranean), 400-500 m depth, sample (n°81) ( Trilles 1964a, 1972a). Also noted: dissected maxilliped, P5-P7 damaged or missing, pleopod 1-2 missing, uropods missing, antennae on one side missing. Paralectotype. Male (6 mm TL), same data as lectotype (MNHN-IU-2007-4028) ( Trilles 1964a, 1972a).

Description.

Lectotype female. Length 16 mm, width 8 mm.

Body oval, 1.7 times as long as greatest width, dorsal surfaces smooth and polished in appearance, widest at pereonite 5, most narrow at pereonite 1, lateral margins posteriorly ovate. Cephalon 0.5 times longer than wide, visible from dorsal view, triangular. Frontal margin rounded to form blunt rostrum. Eyes oval with distinct margins, one eye 0.3 times width and length of cephalon. Antennula more stout than antenna. Antenna with 8 articles.

Pereonite 1 smooth, anterior border straight, anterolateral angle acute, anteriorly produced, extend to anterior margin of eyes. Posterior margins of pereonites smooth and slightly curved laterally. Coxae 2-3 narrow; 4-7 with rounded point; not extending past pereonite margin. Pereonites 1-5 increasing in length and width; 6-7 decreasing in length and width; 6 and 7 narrower and becoming more progressively rounded posteriorly. Pleon with pleonite 1 most narrow, visible in dorsal view; pleonites posterior margin smooth, mostly concave. Posterolateral angles of pleonite 2 narrowly rounded.

Pereopod 1 basis 1.7 times as long as greatest width; ischium 0.8 times as long as basis; merus proximal margin with bulbous protrusion; carpus with straight proximal margin; propodus 1.6 times as long as wide; dactylus slender, 1.1 times as long as propodus, 2.9 times as long as basal width. Pleonites 3-5 similar in form to pleonite 2; pleonite 5 free, not overlapped by lateral margins of pleonite 4, posterior margin produced medially. Pleotelson 0.6 times as long as anterior width, dorsal surface with 2 sub-medial depressions, lateral margins weakly convex, posterior margin subtruncate.

Size.

Female: 13-20 mm TL; male: 6-7 mm TL; second pullus: 2.5-3.5 mm TL ( Trilles 1964a, 1972a, b).

Distribution.

Throughout the Mediterranean with records from France ( Trilles 1964a); Tunisia ( Trilles and Raibaut 1973); Straits of Gibraltar and the Alborán Sea (southern Iberian Peninsula) ( Rodríguez-Sánchez et al. 2001); Turkey ( Kirkim et al. 2008, Innal and Kirkim 2012); Cyprus ( Kirkim et al. 2009); and Yemen ( Al-Zubaidy and Mhaisen 2013).

Rodríguez-Sánchez et al. (2001) stated that Ceratothoa capri was found in the Atlantic and Mediterranean Sea including the Bay of Biscay ( Bolívar 1892), Canary Islands ( Koelbel 1892) and the Iberian Mediterranean ( Barceló Combis 1875, Balcells 1953, Trilles 1977). None of these papers quoted by Rodríguez-Sánchez et al. (2001) mention Ceratothoa capri , and it is possible that these were erroneous reference entries for this species. These references were probably intended for Ceratothoa oestroides , which is mentioned in each of these articles and was also collected by Rodríguez-Sánchez et al. (2001). Junoy and Castello (2003) repeated this lapsus of the references in their checklist for the Iberian Peninsula and Balearic Islands. Rodríguez-Sánchez et al. (2001) also made reference to specific GPS co-ordinates in their paper which appear inaccurate as they correspond to localities on land instead of the expected aquatic points necessary for an oceanographic expedition.

Hosts.

On the branchio-spines in the gill and on the bottom of the buccal cavity of Capros aper (see Trilles 1964a, 1972a, Trilles and Raibaut 1973); from the buccal cavity of Boops boops and Spicara smaris (see Kirkim et al. 2008, Innal and Kirkim 2012); Centracanthus cirrus (see Kirkim et al. 2009); and Chelon macroleps (see Al-Zubaidy and Mhaisen 2013).

Remarks.

Ceratothoa capri can be distinguished by the acute anterolateral margins which extend past the prominent eyes; body widest at pereonite 5; a narrow pleotelson; and no appendix masculina on the second pleopod in males.

There are a number of species of Ceratothoa in the Mediterranean; however Ceratothoa capri differs from them all. There are several differences between Ceratothoa capri and Ceratothoa gobii but the most obvious is the bilobed pleotelson in Ceratothoa gobii which is absent in Ceratothoa capri . The defining pereonite 1 characters of Ceratothoa collaris are absent in Ceratothoa capri and differences between Ceratothoa capri and Ceratothoa italica include less developed eyes, acute and produced anterior margin of the cephalon and the more truncate body of Ceratothoa italica . Similar characters separate it from Ceratothoa steindachneri as well as the number of articles of the antennae and Ceratothoa oxyrrhynchaena differs from Ceratothoa capri in the shape of the 7th pereopod basis of the female. Lastly, Ceratothoa oestroides is less globular or elliptical when compared to Ceratothoa capri ; is darker in the post-cephalic region due to more chromatophores; has shorter uropods; and a more stout body.

In the original description of this species, Trilles (1964a) did not designate a holotype; however, full descriptions of the female, male and second pullus were given along with figures of each. Several years later, Trilles (1972a) listed a male and female Ceratothoa capri located in the buccal cavity of Capros aper from the Gulf of Lion, Mediterranean, which he stated were the types for the species. Examination of these specimens confirms that they are the syntypes of Ceratothoa capri . The female specimen is here designated as lectotype and redescribed. This lectotype is necessary to fix and stabilise the identity of this species and use of the name.