Peltodoris, BERGH, 1880

Valdés, Ángel, 2002, A phylogenetic analysis and systematic revision of the cryptobranch dorids (Mollusca, Nudibranchia, Anthobranchia), Zoological Journal of the Linnean Society 136 (4), pp. 535-636 : 585-591

GENUS PELTODORIS BERGH, 1880

Peltodoris Bergh, 1880: 41 . Type species: Peltodoris atromaculata Bergh, 1880 , by subsequent designation by O’Donoghue (1929).

Phialodoris Bergh, 1889: 908 . Type species: Phialodoris podotria Bergh, 1889 , by monotypy, syn. nov.

Montereina MacFarland, 1905: 38 . Type species: Montereina nobilis MacFarland, 1905 , by original designation, syn. nov.

Diagnosis

Dorsum covered with simple tubercles, stiffened by integumentary spicules, which occasionally protrude from the dorsal surface in an irregular fashion. Head with two conical oral tentacles. Anterior border of the foot grooved and notched. Labial armature smooth. Radula composed of simple, hamate teeth. The outermost teeth may be simple or denticulate. Reproductive system with a flattened, granular prostate, having two well differentiated regions. Penis and vagina devoid of hooks. Vestibular or accessory glands absent.

Remarks

Bergh (1880) described the genus Peltodoris based on Peltodoris atromaculata Bergh, 1880 . Peltodoris is characterized by having the dorsum covered with tubercles, finger-like oral tentacles, tripinnate gill, labial armature without jaws, radula with simple, hamate teeth, large prostate and penis and vagina unarmed. Bergh (1880) distinguished Peltodoris from Discodoris on the basis of the harder body consistency and especially because of the lack of jaws.

Bergh (1889) introduced the new genus Phialodoris based on Phialodoris potrida Bergh, 1889 from Amboine. He regarded Phialodoris as very close to Discodoris and Peltodoris , and only distinguishable from the latter by the peculiar shape of the penis. The penis of Phialodoris potrida is cylindrical with a cup-shaped apex armed with very small cones. Other characteristics of this species are similar to those of other members of Peltodoris , including the absence of jaws. There is no doubt that Phialodoris is a synonym of Peltodoris , and the peculiar penis shape is probably due to a preservation artifact or interspecific variation.

MacFarland (1905) described the genus Montereina based on Montereina nobilis MacFarland, 1905 . The diagnostic features of this genus are firm body, tuberculate dorsum, long and conical tentacles, large gill, differentiated prostate and vagina and penis unarmed. No further species have been assigned to this genus, which was later synonymized with Anisodoris Bergh, 1898 by MacFarland (1906). According to Valdés & Gosliner (2001), the genus Anisodoris , which is a synonym of Diaulula Bergh, 1878 , is characterized by having the dorsum covered with caryophyllidia. The anatomy of M. nobilis is similar to that of species of Peltodoris , and both names are here regarded as synonyms. Other species from the Pacific coast of South America, such as Doris variolata d’Orbigny, 1837 , previously assigned to the genus Anisodoris , should also probably be transferred to Peltodoris .

Eliot (1906b) pointed out that Peltodoris only differs from Discodoris in lacking a labial armature (jaws) and it should be regarded as a subgenus of Discodoris . Later, Thompson (1975) synonymized Peltodoris with Discodoris with no justification. In the following years a few authors followed Thompson’s authority and cited the type species of Peltodoris in the binomen Discodoris atromaculata ( Cattaneo-Vietti et al., 1990) . However, most authors maintained the usage of Peltodoris as a valid genus ( Castiello et al., 1980; Barletta, 1981; Schmekel & Portmann, 1982; Jonas, 1986; Perrone, 1992; Ávila, 1996).

The phylogenetic analysis carried out in the present paper indicates that Discodoris and Peltodoris belong in two different clades (see below); therefore, the genus Peltodoris is retained as valid.

PELTODORIS ATROMACULATA BERGH, 1880

( FIGS 4H , 28 , 29 )

Peltodoris atromaculata Bergh, 1880: 45–46 .

Type material

SYNTYPE: Naples , Italy, spring of 1880, one specimen, 34 mm preserved length ( ZMUC GAS-2054 )

Additional material

Islas Medas, La Escala, west coast of Gerona , Spain, three specimens, 25–34 mm preserved length, leg. T . M. Gosliner ( CASIZ 099147 ). Cala Salada, Ibiza, Spain, one specimen, 49 mm preserved length, leg. A. Valdés ( CASIZ 119474 ). 1 km east of Caloura , Ilha São Miguel , Azores, Portugal, eight specimens, 44–67 mm preserved length, leg. T . M. Gosliner ( CASIZ 072584 ) .

External morphology

The general colour of the living animals is whitish to pale cream ( Fig. 4H ). There is a number of dark brown or black large patches distributed on the dorsum, varying in shape and size. The rhinophores and gill are white or pale cream. The branchial leaves have some small dark brown or black spots. The whole dorsum is covered with small, conical tubercles, which have spicules protruding on their dorsal surface ( Fig. 28D ). The largest tubercles are situated in the central region of the body. The rhinophoral and branchial sheaths have tubercles similar to those of the rest of the dorsum. There are six 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 22 lamellae in a 52-mm preserved length specimen.

Ventrally there are two short and conical oral tentacles ( Fig. 29F ). 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. 29D ) which attach to the body wall. The oval, muscular buccal bulb has two additional muscles attached; two long salivary glands connect with it at each side of the oesophageal junction. The buccal bulb is longer than the glandular portion of the oral tube. The labial cuticle is smooth. The radular formula is 22 ¥ 48.0. 48 in a 54-mm preserved length specimen. Rachidian teeth are absent. The inner lateral teeth are short, having a long, curved cusp and lacking denticles ( Fig. 28A ). They also have a secondary, short and blunt cusp situated behind the main cusp. The teeth from the middle portion of the half-row are hamate, long and larger than those closer to the medial portion of the radula ( Fig. 28B ). The outermost teeth are smaller and also smooth ( Fig. 28C ). The oesophagus is short and connects directly to the stomach ( Fig. 29A ).

The ampulla is long and thin, and branches into a short oviduct and the prostate ( Fig. 29C ). The oviduct enters the female gland mass near to its centre. The prostate is flattened, long, folded and granular ( Fig. 29B ), with two differentiated portions distinguishable by their colour and texture. It connects with a long duct that narrows and expands again into the small ejaculatory portion of the deferent duct. The muscular deferent duct opens into a common atrium with the vagina. The vagina is long. Near to its proximal end it joins the bursa copulatrix. From the bursa copulatrix leads another duct that connects to the seminal receptacle and the uterine duct. The bursa copulatrix is oval in shape, about 10 times as large as the seminal receptacle.

In the central nervous system ( Fig. 29E ) the cerebral and pleural ganglia are fused and distinct from the pedal ganglia. There are four cerebral nerves leading from the left cerebral ganglion and three from the right one, 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 long nerves. Gastro-oesophageal, rhinophoral and optical ganglia are present. The pedal ganglia are clearly separated, having four nerves leading from each one. The pedal and parapedal commissures are enveloped together with the visceral loop.

The circulatory system ( Fig. 29A ) consists of a large heart and a two blood glands situated in front of and behind the central nervous system.

PELTODORIS NOBILIS ( MACFARLAND, 1905)

( FIGS 4I , 30 , 31 )

Montereina nobilis MacFarland, 1905: 38–39 .

Type material

HOLOTYPE (by original designation): Monterey Bay, California, leg. F. M. MacFarland ( USNM 181284 ), not examined.

Additional material

Pacific Grove , Monterey Bay, California, USA, July– August 1923 and May 1926, 10 specimens, 24–67 mm preserved length, leg. F. M. MacFarland ( CASIZ 068237 ) .

External morphology

The general colour of the living animals varies from whitish to orange-yellow ( Fig. 4I ). There is a number of dark brown or black small spots distributed on the entire dorsum below the level of the tubercles. The rhinophores have a light yellow base and a orange club. The gill is pale yellow with the apices of the leaves opaque white. The whole dorsum is covered with small, rounded tubercles ( Fig. 30D ). The largest tubercles are situated in the central region of the body. The rhinophoral and branchial sheaths have tubercles no different from those on the rest of the dorsum. There are five 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 17 lamellae in a 54-mm preserved length specimen.

Ventrally there are two long and conical oral tentacles ( Fig. 31E ). 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. 31D ) which attach to the body wall. The oval, muscular buccal bulb has two additional muscles attached; two long and wide salivary glands connect with it at each side of the oesophageal junction. The buccal bulb is twice the length of the glandular portion of the oral tube. The labial cuticle is smooth. The radular formula is 27 ¥ 57.0. 57 in a 54-mm long specimen. Rachidian teeth are absent. The lateral teeth are narrow and elongate, having a single cusp and lacking denticles ( Fig. 30A ). The teeth from the middle portion of the half-row are larger than those closer to the medial portion of the radula ( Fig. 30B ). The outermost teeth are smaller and also lack denticles ( Fig. 30C ). The oesophagus is short and connects directly to the stomach ( Fig. 31A ).

The ampulla is very long and convoluted ( Fig. 31C ). It branches into a short oviduct and the prostate. The oviduct enters the female gland mass near to its centre. The prostate is flattened and has two portions distinguishable by their colour and texture ( Fig. 31B ). 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. The vagina is long and convoluted. 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 eight times as large as the seminal receptacle ( Fig. 31B ).

In the central nervous system ( Fig. 31D ) 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 relatively short nerves. Gastrooesophageal, rhinophoral and optical ganglia are present. The pedal ganglia are clearly separated, having four nerves each one. The pedal and parapedal commissures are enveloped together with the visceral loop.

The circulatory system ( Fig. 31A ) consists of a large heart and a two blood glands situated in front of and behind the central nervous system.

Remarks

Peltodoris nobilis is a well-known species from the Pacific Coast of North America (see McDonald, 1983). It was originally described in the genus Montereina ( MacFarland, 1905) and later transferred to the genus Anisodoris .

Figures

Figure 4. Living animals. A, Doris pseudoargus (CASIZ 121105). B, Doris immonda (CASIZ 089023), photo by T. M. Gosliner. C, Doris granulosa (CASIZ 073536), photo by T. M. Gosliner. D, Discodoris boholiensis (CASIZ 083654), photo by T. M. Gosliner. E, Discodoris ketos, San Pedrillo, Puntarenas, Costa Rica, photo by T. M. Gosliner. F, Thordisa rubescens (CASIZ 015860), photo by T. M. Gosliner. G, Aphelodoris antillensis (CASIZ 077289), photo by T. M. Gosliner. H, Peltodoris atromaculata (CASIZ 119474). I, Peltodoris nobilis, Monterey Bay, California, photo by A. Smith.

Figure 28. Peltodoris atromaculata (CASIZ 072584), SEM images of the radula and dorsal tubercles. A, inner lateral teeth; scale bar = 75 Mm. B, mid-lateral teeth; scale bar = 250 Mm. C, outer lateral teeth; scale bar = 150 Mm. D, dorsal tubercles; scale bar = 250 Mm.

Figure 29. Peltodoris atromaculata (CASIZ 072584). A, general view of the anatomy; scale bar = 1 mm. B, reproductive system; scale bar = 1 mm. C, detail of several reproductive organs; scale bar = 1 mm. D, lateral view of the buccal bulb; scale bar = 1 mm. E, central nervous system; scale bar = 0.5 mm. F, ventral view of the mouth area; scale bar = 1 mm.

Figure 30. Peltodoris nobilis (CASIZ 068237), SEM images of the radula and dorsal tubercles. A, inner lateral teeth; scale bar = 200 Mm. B, mid-lateral teeth; scale bar = 200 Mm. C, outer lateral teeth; scale bar = 150 Mm. D, dorsal tubercles; scale bar = 1 mm.

Figure 31. Peltodoris nobilis (CASIZ 068237). A, general view of the anatomy; scale bar = 1 mm. B, reproductive system; scale bar = 1 mm. C, detail of several reproductive organs; scale bar = 1 mm. D, central nervous system; scale bar = 0.5 mm. E, ventral view of the mouth area; scale bar = 1 mm. F, lateral view of the buccal bulb; scale bar = 1 mm.