Paradoris indecora

PARADORIS INDECORA (BERGH, 1881)

(FIGS 34A, 35, 36)

Discodoris indecora Bergh, 1881: 108–112, pl. J, figs 26–33, pl. K, figs 11–19.

Paradoris granulata Bergh, 1884a: 686–691, pl. 76, figs 10–24.

Paradoris granulata var. Bergh, 1884a: 691–693, pl. 77, figs 25–32.

Type material

Discodoris indecora Bergh. The original type material, collected from Trieste, Italy, is lost. Paradoris granulata Bergh, 1884. LECTOTYPE (here selected): Trieste, Italy, April–May 1979 – 80, 24 mm preserved length, leg. Graeffe (ZMUC GAS-2120); PARALEC TOTYPES: Trieste, Italy, April–May 1979 –80, six specimens, 8–24 mm preserved length, leg. Graeffe (ZMUC).

Two other specimens labelled as Paradoris granulata var. belong to the same species. They were probably collected from Trieste, Italy, April–May 1979 –80, 11– 19 mm preserved length, leg. Graeffe (ZMUC GAS- 2121).

Additional material

Cabo de Palos, Murcia, Spain, 4 August 1984, one specimen, 14 mm preserved length, leg. J. Templado (MNCN 15.05 /18231).

External morphology

The general colour of the living animals is uniformly pale grey with a pale brown tinge in the centre of the dorsum (Fig. 34A). There are several dark brown spots on the tips of the larger tubercles, also associated with groups of small opaque white dots. The rhinophores are dark brown with the apex and some spots opaque white. The gill is pale grey with the apices of the leaves bright yellow and dark brown. The whole dorsum is covered with small, rounded tubercles (Fig. 35E). The largest tubercles occur in two lines running from the rhinophores to the gill. The rhinophoral and branchial sheaths have tubercles no different from those on the rest of the dorsum. There are eight tripinnate branchial leaves, forming a circle. The anal papilla is situated in the centre of the branchial circle of leaves. The rhinophores are elongate, having 14 lamellae in a 24-mm preserved length specimen.

Ventrally there are two long and conical oral tentacles (Fig. 36E). The tentacles are grooved longitudinally. The anterior border of the foot is grooved and notched.

Anatomy

The posterior end of the glandular portion of the oral tube has six strong retractor muscles (Fig. 36C) which attach to the body wall. The oval, muscular buccal bulb has two additional muscles attached; two long and thin salivary glands connect with it at each side of the oesophageal junction. The buccal bulb is half the length of the glandular portion of the oral tube. The labial cuticle has two areas covered with a number of simple rodlets (Fig. 35D). The radular formula is 20 ¥ 22.0. 22 in a 24-mm long specimen. Rachidian teeth are absent. The lateral teeth are narrow and elongate, having a single cusp and lacking denticles (Fig. 35A). The teeth from the middle portion of the half-row are larger than those closer to the medial portion of the radula, and they have a short and strong cusp compared to the base (Fig. 35B). The outermost teeth are smaller and also lack denticles (Fig. 35C). Some of them completely lack a cusp. The oesophagus is long and connects directly to the stomach (Fig. 36A).

The ampulla is very long and convoluted (Fig. 36C). It branches into a short oviduct and the prostate. The oviduct enters the female gland mass near to its centre. The prostate is tubular and has two portions distinguishable by their colour and texture (Fig. 36B). It connects with a long duct that narrows and expands again into the large ejaculatory portion of the deferent duct. The muscular deferent duct opens into a short common atrium with the vagina. Connected to the atrium there us a large, ramified accessory gland and two muscular sacs each containing a rigid spine. The vagina is long and thin. At its proximal end it joins the bursa copulatrix. From the bursa copulatrix leads another duct connecting to the uterine duct and the seminal receptacle. The bursa copulatrix is oval in shape, about four times as large as the seminal receptacle (Fig. 36B).

In the central nervous system (Fig. 36D) the cerebral and pleural ganglia are fused and distinct from the pedal ganglia. There are three cerebral nerves leading from each cerebral ganglion and three pleural nerves leading from each pleural ganglion. There is a separate abdominal ganglion on the right side of the visceral loop. The buccal ganglia are near to the rest of the central nervous system, joined to the cerebral ganglia by two relatively short nerves. Gastrooesophageal, rhinophoral and optical ganglia are present. The pedal ganglia are clearly separated, having two nerves each one. The pedal and parapedal commissures are enveloped together with the visceral loop.

The circulatory system (Fig. 36A) consists of a large heart and a two blood glands situated in front of and behind the central nervous system.

Remarks

Ortea (1995) revised the Atlantic species of Paradoris and concluded that Paradoris granulata Bergh, 1884, the type species of the genus, is a junior synonym of Discodoris indecora Bergh, 1881. The material from the Mediterranean examined here is identical to Ortea’s (1995) redescription of this species. He also described more new species from the area that appear to be distinct in several anatomical details.