BASTERIA, 65: 61-68, 2001 A new of Nudibranchiaofthe species genusDoriopsilla Bergh (Gastropoda, Opisthobranchia) from SouthAfrica Antonio+S. Perrone Via Palermo 7, 73014 Gallipoli, Italy A of the nudibranch new species genus Doriopsilla Bergh, 1880,D. debruini, is described from Hout South is Bay, Africa. The new species distinguished externally by a number oflarge dark brown the of sheaths and notch patches, presence high rhinophore a very deep on the ante- rior foot. the of the is for the with the Internally arrangement organs typical genus presence of female and flat Differences between the a large gland a prostatic gland. known species are tabulated. Key words: Opisthobranchia, Nudibranchia, Dendrodorididae, Doriopsilla, South Africa, taxonomy. INTRODUCTION The genus Doriopsilla (family Dendrodorididae) was established by Bergh (1880) and the type species, Doriopsilla areolata, was described from the MediterraneanSea. Further known from Doriopsilla species are different seas (Alder & Hancock, 1864; D'Oliveira, 1895; Baba, 1949; Marcus, 1961; Burn, 1962, 1989; Marcus & Marcus, 1967; Edmunds, 1968; Meyer, 1977; Valdes & Behrens, 1998; Gosliner, Schaefer & Millen, 1999, etc.). Some ascribed Dendrodoris Doriopsilla species were to (Allan, 1933; Pruvot-Fol, 1951, 1954; Behrens, 1980, 1991; McDonald & Nybakken, 1981; McDonald, 1983; Baba, 1933, since 1949) the two are similar. the was genera superficially Recently genus Doriopsilla reviewed Valdes but (Valdes, 1996; & Ortea, 1997) the numberof valid species is uncer- tain. Four species are known from South Africa (Bergh, 1907; Gosliner, 1987) and only of these named. One of the unnamed South African two are species shows the typical habitus of Doriopsilla but with a peculiar pattern consisting of large darkbrown patches brown notal The on a pale background. present species is part of a collection of nudi- branchs from South Africa and it is here described as a new species. METHODS observed the Living specimens were in field, collectedby SCUBA and relaxed in a 7% C12 solutionmixed with an volume of seawater frozen The Mg. equal or in seawater. spe- cimens fixed 10% buffered formalin - were in a seawater solution and preserved in 70% ETOH. The material was dissected under Leica MZ and preserved a microscope anat- omical illustrations made were using a drawing tube. Anatomical preparations were stai- ned with methylene blue or carmine and studied by light microscopy. 62 BASTERIA, Vol. 65, No. 1-3, 2001 DESCRIPTION nov. 1A—B, 2A-C, 3A- F, Doriopsilla debruini spec. (figs 4A—B) 1, 1987: 89, 150. Doriopsilla sp. Gosliner, fig. 1-10 B. Material. — South Africa, Cape Peninsula, (1) Hout Bay, m depth, under stone, XII.1999, De Bruin, 1 specimen, microscope slides, colour transparencies, ASP 5357; (2) Hout Bay, 1-10 m depth, under stones, XII.1999, B. De Bruin, 2 specimens, microscope slides, colour transparencies, ASP 5400 - 5401; (3) Hout XII. B. De Bruin, 1 colour Bay, 1-10 m depth, under stone, 1999, specimen, transparencies (holotype), B. 2 Museum ofZoology, Roma; (4) Hout Bay, 1-10 m depth, under stones, XII. 1999, De Bruin, specimens, microscope slides, colour transparencies, ASP 5403 - 5404. — The have with stiffe- Morphology. living specimens a rigid notum, a rough texture ned by a subepidermal network ofneedle-shaped calcareous spicules, and range from 23- The dorsum covered with rounded tubercles of dif- 37 mm in length (fig. 1A-B). entire is ferent sizes stiffened by needle-shaped calcareous spicules (fig. 3A). These spicules are and their from the The back- radially arranged points are slightly projecting epidermis. ground colour of the notum and the foot is pale brown. The pattern on the dorsum con- of than of dark brown The sists a number, usually more 20, patches (fig. 2A-C). patches have a uniform pigmentation but in some specimens the centre of each patch is paler thanthe edge (fig. 3A). The largest tubercles are sparsely distributed but frequent on the the The brown central notum, slowly decreasing in size towards margin. orange rhinop- hores be withdrawn into sheaths. Each sheath is with 8 may high rhinophoral provided or more tubercles on its upper margin (fig. 3C). The rhinophores are perfoliate with lamellae There more than 20 oblique (fig. 3B). are nine tripinnate gills surrounding an The tentacles with ventral eccentric strong anal papilla. oral are long, a groove. They are fused only on their proximal tract and developed in a transversal direction (fig. 3F). The visible anterior borderof the foot has a deep median notch, where the buccal aperture is and overlies the oral tentacles. — buccal Anatomy. The mouth (fig. 3F) leads, through a vestibule, into a strongly mus- cular pharyngeal bulb, oval in shape and without radula. The tubular pharynx passes through the central nerve ring leading into the straight, cylindrical oesophagus (fig. 4A). Then it enters the brown digestive gland. The intestine comes to the surface in front of the heart. It crosses the proximal aorta and curves to the right, reaching the anal papilla with a loop. Some specimens show a round protuberance at the point of the intestinal emersion (pyloric caecum), but in large specimens this is not evident. The nervous has the of the with the buccal close the system typical arrangement genus, ganglia by central ring. The reproductive system is characterized by a bulky, pink coloured female gland (nidamental gland plus white mucous gland). The ovotestis is visible on the digesti- A ve gland as a pale yellow layer on the maroon background. short hermaphroditic duct leads into an elongate and convoluted ampulla. The ampulla becomes narrower and enters the female gland. The vaginal duct and the proximal deferent duct enter the fema- le the The flattened lobe gland at same point (fig. 4B). prostatic gland is a large covering the whitish vesicles and part of the female gland. The deferent duct is wider than the duct 4B these two ducts into vaginal (fig. 4B), running together (in fig. are spaced out) a common atrium. Penial hooks are hardly observed on the internal wall ofthe distal defe- duct with the duct ends with rent no apparent regular arrangement. Proximally vaginal Perrone: A new Doriopsilla from S. Africa 63 1. A, Fig. Doriopsilla debruini, Hout Bay, South Africa, 26 mm long; B, D. debruini holotype, Hout Bay, South Africa, 28 mm long; photographs A. S. Perrone. a soft bag-shaped bursa copulatrix. The aorta runs from the heart to a narrow and flat coloured blood pale gland (fig. 4A). The heart and the aorta are ochre or dark red in fresh material. Ecology. — Specimens of Doriopsilla debruini were encountered under stones in subti- dal communities.No associated observed. sponge was 64 BASTERIA, Vol. 65, No. 1-3, 2001 Fig. 2. Doriopsilla debruini,pattern. A, dorsal view; B, ventral view; C, side view. Distribution. — Doriopsilla debruini spec. nov. is known only from Hout Bay, South Africa. Etymology. — The epithet is after the collector, Bruno De Bruin. Discussion. — Doriopsilla and Dendrodoris are both included in the family Dendrodorididae.The two taxa share the absence ofa radulaand the labial cuticle as a of method. Inboth taxa the oral tentacles consequence a convergent sucking feeding are duct armed with reduced but show a variety of shapes and the deferent is hooks, Perrone: A new Doriopsillafrom S. Africa 65 Fig. 3. Doriopsilla debruini, morphology. A, arrangement of the notal tubercles; B, rhinophore; of the foot C, rhinophore sheaths; D, upper margin gill pocket; E, gill circlet; F, anterior and oral tentacles. Abbreviations: the tubercles. AN, anus; GR, groove; M, mouth; PAT, patch on notum; TB, 66 BASTERIA, Vol. 65, No. 1-3, 2001 4. A, dorsal view of the dissected the Fig. Doriopsilla debruini, anatomy. anatomy; B, reproductive organs, is Abbreviations: AN, AO, BC, bursa BG, blood DG, ampulla omitted. anus; aorta; copulatrix; gland; digesti- ve gland; FG, female gland; H, heart; I, intestine; OT, oral tube; P, penis; PH, tubular pharynx; PR, prostatic gland; VGD, vaginal duct. Doriopsilla differs fromDendrodorisin the following characters: (1) a rigid body stiffened inDendrodoris the by spicules (spicules are present during juvenile stage); (2) a develop- ed network of spicules in the notum and foot, often with a regular arrangement; (3) tubercles stiffened left ofthe the by spicules; (4) eccentric position anus in gill circlet; (5) a groove on the reduced oral tentacles; (6) absence ofthe ptyaline gland; (7) position of the buccal ganglia close by the central ring; (8) the proximal connection of the seminal vesicles. The flat shape of the prostate is a widespread feature and it was proposed as a of for Ortea, However, character diagnostic value the genus Doriopsilla (Valdes & 1997). since at least three species of Doriopsilla have a tubular prostatic gland (table 1), the flat prostate should not be a diagnostic characterof the genus. Doriopsilla appears to be a not very diverse genus but dataobtained from literature are members The not sufficient for an adequate comparison of all its (table 1). new species, D. debruini, has the diagnostic characters of Doriopsilla and clearly belongs to this genus. Perrone: A S. new Doriopsilla from Africa 67 It shares the background notal colourwithDoriopsilla laevis Beigh, 1905, but the latter is a poorly known species and its taxonomic status should be considered uncertain.A dark of phase Doriopsilla peculiaris was reported by Burn (1989). Its colourresembles that ofD. debruinibut it differs in the and the of white The cream tonality pattern opaque spots. presence oflarge dark brown patches on the notum is a unique pattern amongDoriopsilla while it is in Dendrodoris. External ofD. debruini the spp., widespread autapomorphies are of following: (1) presence high rhinophore sheaths; (2) a very deep notch on the anteri- or foot. D. debruini has long and transversally developed oral tentacles. Long tentacles are reported for D. pharpa (Valdes & Ortea, 1997) and D.