Discodoris boholiensis BERGH 1877
Creators: name: Valdés, Ángel
Publisher: name: Zenodo
Year: 2002
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Nudibranchia
Discodorididae
Discodoris
Discodoris boholiensis

description: DISCODORIS BOHOLIENSIS BERGH, 1877
(FIGS 4D, 15, 16)
Discodoris boholiensis Bergh, 1877a: 519–522, pl. 60, fig. 23, pl. 61, figs 6–12.
Discodoris meta Bergh, 1877a: 522–526, pl. 60, figs 24, 25, pl. 61, figs 25–28.
Type material
SYNTYPES of Discodoris boholiensis: Bohol, Aibukit, Philippines, date unknown, three specimens, 45 mm (decapitated) 70 mm preserved length, leg. C. Semper (ZMUC GAS-2122). HOLOTYPE (by monotypy) of Discodoris meta: Cebu, Ubay, Philippines, leg. C. Semper (ZMUC).
Additional material
North side of Sombrero Island, Batangas, Luzon, Philippines, 19 February 1992, three specimens, 20– 49 mm preserved length, leg. T. M. Gosliner (CASIZ 083654).
External morphology
The background colour of the living animals varies from pale cream in the centre of the dorsum to pale ochre near to the mantle edge (Fig. 4D). The dorsum is covered with a number of rounded white spots situated on each dorsal tubercle. These white spots are more densely concentrated on the mantle margin, forming several radial white lines. There is an irregular pattern of dark brown patches and lines on the centre of the dorsum, from behind the rhinophores to the gill. A similar pattern also occurs near to the mantle edge. Both areas are connected by irregular, faded pale brown lines forming a broken network. The rhinophoral and branchial sheaths are elevated and surrounded by a dark brown line, which in the case of the branchial sheath is interrupted by several white spots. The rhinophores are dark brown to black, with several irregular white lines. The branchial leaves are also dark brown, almost black, with dark grey rachises. The whole dorsum is covered with small, conical tubercles, which have spicules protruding on their dorsal surface (Fig. 15E). The largest tubercles are situated in the central region of the body. The rhinophoral and branchial sheaths have tubercles similar to those on the rest of the dorsum. There are six tripinnate branchial leaves. The anal papilla is situated in the centre of the branchial circle of leaves. The rhinophores are elongate, having 26 lamellae in a 49-mm preserved length specimen.
Ventrally the anterior border of the foot is grooved and notched (Fig. 16F). The oral tentacles are elongate, with a blunt apex.
Anatomy
The posterior end of the glandular portion of the oral tube has six strong retractor muscles (Fig. 16E) which attach to the body wall. The oval, muscular buccal bulb has two large additional muscles attached; two long salivary glands connect with it at each side of the oesophageal junction. The buccal bulb is shorter than the glandular portion of the oral tube. The labial cuticle is armed with a number of small, simple rodlets (Fig. 15D). The radular formula is 29 ¥ 35.0. 35 in a 49- mm long specimen. Rachidian teeth are absent. The lateral teeth are hamate and lack denticles (Fig. 15A). The teeth from the middle portion of the half-row are larger than those closer to the medial portion of the radula (Fig. 15B). The outermost teeth are smaller and also lack denticles (Fig. 15C). The oesophagus is short and connects directly to the stomach (Fig. 16A).
The ampulla is long and simple (Fig. 16C). It branches into a short oviduct and the prostate. The oviduct enters the female gland mass near to its centre. The prostate is large and flattened. It has two different portions that are clearly distinguishable in colour and texture (Fig. 16B). The prostate connects with a very long and convoluted duct that narrows and expands again into the large ejaculatory portion of the deferent duct. The penis is unarmed. The muscular deferent duct opens into a common atrium with the vagina. The vagina is long. 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 rounded in shape, about three times as large as the seminal receptacle.
In the central nervous system (Fig. 16D) the cerebral and pleural ganglia are fused and distinct from the pedal ganglia. There are three cerebral nerves leading from each cerebral ganglion and two 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 long nerves. Gastro-oesophageal, rhinophoral and optical ganglia are present. The pedal ganglia are clearly separated, having two nerves leading from the left ganglion and three from the right one. The pedal and parapedal commissures are enveloped together with the visceral loop.
The circulatory system (Fig. 16A) consists of a large heart and two blood glands situated in front of and behind the central nervous system.
Remarks
Discodoris boholiensis is a well-known Indo-Pacific species characterized by having a background brown colour with black and white spots and lines on the body, and a relatively flat dorsum with undulating margins and a prominent central hump. Examination of the type material of Discodoris meta Bergh, 1877 confirmed that it is a synonym of D. boholiensis.
description: Published as part of Valdés, Ángel, 2002, A phylogenetic analysis and systematic revision of the cryptobranch dorids (Mollusca, Nudibranchia, Anthobranchia), pp. 535-636 in Zoological Journal of the Linnean Society 136 (4) on pages 565-566, DOI: 10.1046/j.1096-3642.2002.00039.x, http://zenodo.org/record/4634200