Spurilla undetermined

Carmona, Leila, Lei, Bonnie R., Pola, Marta, Gosliner, Terrence M., Valdés, Ángel & Cervera, Juan Lucas, 2014, Untangling the Spurilla neapolitana (Delle Chiaje, 1841) species complex: a review of the genus Spurilla Bergh, 1864 (Mollusca: Nudibranchia: Aeolidiidae), Zoological Journal of the Linnean Society 170 (1), pp. 132-154 : 144-146

publication ID	https://doi.org/ 10.1111/zoj.12098
persistent identifier	https://treatment.plazi.org/id/03A32C78-1559-E410-FC30-BD7EFE69FEF0
treatment provided by	Carolina
scientific name	Spurilla undetermined
status	SP.

Treatment

SPURILLA ONUBENSIS SP. NOV.

( FIGS 3D View Figure 3 , 5A View Figure 5 , 6A–B View Figure 6 )

Spurilla sp. A View in CoL : Just & Edmunds (1985: 144, pl. 68, figs A–D).

Spurilla sp. A View in CoL : Carmona et al. (2013: 6).

Material examined

Holotype: MNCN 15.05 About MNCN /60081, one specimen, dissected, 15 mm in length preserved, Spain, Huelva, El Portil, collected by Sergio García-Gómez, iv.09, deposited at MNCN.

Paratype: MNCN 15.05 About MNCN / 60082, one specimen, dissected, 18 mm in length preserved, Spain, Huelva, El Portil, collected by Sergio García-Gómez, iv.09, deposited at the MNCN.

More material: MNCN 15.05 About MNCN /66445, one specimen, dissected, 15 mm in length preserved, Morocco, David (Atlantic Ocean), collected by Naoufal Tamsouri, 23.vii.09 .

Type locality and habitat

Spain, Huelva, El Portil. Found in intertidal area, in tide pools and under the rocks.

Geographical distribution

So far, this species is only known from Arcachon ( France) ( Just & Edmunds, 1985), Huelva (southeastern Spain; present study), and David ( Morocco, Atlantic Ocean; present study).

Etymology

The Latin word onubensis refers to the Spanish Province of Huelva (Onuba during Roman times), which is the hometown of Sergio García-Gómez who kindly provided us with numerous specimens of Aeolidiidae from this area, including material of this new species.

External morphology ( Fig. 5A View Figure 5 )

The body is elongate and moderately broad, tapering gradually to the posterior end. The anterior foot corners extend into tentaculiform processes. The body colour is translucent bright orange. The notum is devoid of any kind of spots, marks, or pigment. The branches of the digestive gland form a reticulate pattern. The latter is restricted to both sides of the head, just below the rhinophores, and forms short branches ( Fig. 5A View Figure 5 ).

The rhinophores, the oral tentacles, and the foot corners have the same colour as the rest of the body. The rhinophores are perfoliate, bearing around ten lamellae, and have white apices. They are slightly shorter than the oral tentacles. The coloration of the tips of the oral tentacles is lighter than the background colour of the animals.

The ceratal length is rather uniform. The cerata are short and thick, with their tips curved inwards. The cerata are arranged in up to 11 arches, leaving a distinct gap between the pre- and post-pericardial groups. The cerata extend from behind the rhinophores to the tail. Each arch contains between two and 27 cerata, decreasing in size towards the foot. The cerata are translucent orange, with translucent white apices. The dark olive green ramifications of the digestive gland are visible through the ceratal wall. The cleioproctic anus is located within the second right arch. The genital aperture is located among the cerata of the most anterior group on the right.

Anatomy

The masticatory border is smooth ( Fig. 6A View Figure 6 ). The radular formulae are 17 × 0.1.0 ( MNCN 15.05/60081, 15 mm), 20 × 0.1.0 ( MNCN 15.05/60082, 18 mm), and 25 × 0.1.0 ( MNCN 15.05/66445, 15 mm). The teeth are progressively smaller towards the posterior region of the radula. The radular teeth are biarched with 24–38 elongate, moderately broad, and acutely pointed denticles on either side of the triangular central cusp ( Fig. 6B View Figure 6 ). The large, composite, and conspicuous oral glands lie dorsolaterally to the buccal bulb. Salivary glands are absent.

The reproductive system is diaulic ( Fig. 3D View Figure 3 ). The preampullary duct widens into the ampulla that narrows again before dividing into the oviduct and vas deferens. The elongate and thin vas deferens enters the wider proximal portion of the penial sac, which contains the unarmed penial papilla. The short oviduct connects to the receptaculum seminis. The remaining portion of the oviduct departs from the base of the receptaculum and enters the female gland. The vagina opens ventral to the penis.

Remarks

Just & Edmunds (1985) compiled unpublished illustrations by Lemche, including one of a Spurilla species under the name Spurilla sp. A (illustrated in plate 68). This plate depicts a specimen with exactly the same colour pattern as our specimens of S. onubensis sp. nov. described herein. Both lack any trace of white spots, clearly visible on the notum and the cerata in other Spurilla species , and have a bright-orange body. Pruvot-Fol (1953) described S. mograbina from Temara ( Morocco), which is close to David (the locality where one of our specimens of S. onubensis sp. nov. was collected), and illustrated a single specimen with opaque cream spots scattered on the dorsal side of the cerata and the notum. Spurilla onubensis sp. nov. is clearly different from S. mograbina as our specimens lack such pigmentation. Although our specimens were initially identified as S. neapolitana (see Carmona et al., 2013), both morphological and molecular data clearly separate Spurilla onubensis sp. nov. from S. neapolitana and the remaining members of this genus.

To date, S. onubensis sp. nov. and S. neapolitana are the only eastern Atlantic species of this genus, but they were not recovered as sister species in the phylogenetic analyses (see molecular results). Furthermore, the geographical range of S. neapolitana overlaps with that of S. onubensis sp. nov.