Portadas 21 (2)

Contributions to West-Mediterranean Solenogastres (Mollusca) with three new species

Contribuciones al conocimiento de los Solenogastres (Mollusca) del Mediterráneo occidental, con tres nuevas especies

Luitfried v. SALVINI-PLAWEN*

Recibido el 1-X-2002. Aceptado el 13-III-2003

ABSTRACT Six species of West-Mediterranean Solenogastres are treated, three of which are described as new to science: Micromenia subrubra n.sp. from off Malta, Macellomenia adenota n.sp. from off Ceuta, Urgorria monoplicata n.sp. from off the Costa Brava. Records of other species ( Nematomenia banyulensis, Tegulaherpia sp. and Eleutheromenia sierra ) contribute to our knowledge of respective geographical distribution. The re-finding of E. sierra also results in the definition of a new genus Scheltemaia n.g. for two South- Australian, former Eleutheromenia species.

RESUMEN Se estudian seis especies de Solenogastres del Mediterráneo occidental, incluyendo tres nuevas especies: Micromenia subrubra n.sp. de Malta, Macellomenia adenota n.sp. de Ceuta, Urgorria monoplicata n.sp. de la Costa Brava. Se aportan informaciones sobre otras especies, Nematomenia banyulensis, Tegulaherpia sp. y Eleutheromenia sierra , que contribuyen a un mejor conocimiento de sus distribuciones. La redescripción de E. sierra justifica la definición de un nuevo género Scheltemaia n.g. para dos especies descritas del Estrecho de Bass, Australia meridional.

KEY WORDS : Mollusca, Solenogastres, geographical distribution, new species. PALABRAS CLAVE: Mollusca, Solenogastres, distribución geográfica, nuevas especies.

INTRODUCTION

The Solenogastres are a small class of digestive gland) and to the lack of partic - aplacophoran Mollusca, characterised by ular excretory organs (no emunctoria), the mantle cover of cuticle and unicellu - they appear to represent a very conserva - larily formed, calcareous mantle bodies tive off-shoot of Mollusca. Apart from the or sclerites (scales, spicules, a.o.) and by plesiomorphic, aplacophoran mantle and the laterally rounded body with the foot a few other features, they are by diphyly narrowed to a longitudinal pedal groove. also clearly different from the Caudo - With respect to the mantle cover, to char - foveata (cf. SALVINI -P LAWEN , 2003). acters of the alimentary tract (no true Solenogastres are generally small radula ribbon, midgut without separate (average 3 mm - 3 cm; rarely longer, up

* Institut für Zoologie, Universität Wien, A-1090 Wien (Vienna/Austria), Althanstrasse 14

37 Iberus , 21 (2), 2003

to 30 cm), and about 230 species are mentary - is of interest. In regard to the nominally known at present. Their revised classification ( SALVINI -P LAWEN purely marine habitats (mostly below 50 1978), systematic problems remain; m depth), their organisation based these also concern several descriptions mainly on internal systematic charac - that are fragmentary compared to the ters, together with the great effort and required standard and await supple - expense required to collect them have mentation or revision. clearly prevented broader assessments The present contribution compiles and a greater familiarity with this Solenogastres from different samplings group. Much material from more recent of the western Mediterranean Sea. Apart collections (expeditions and individual from enlarging our information on samplings) awaits elaboration and will organisational diversity and providing no doubt contribute to a still fairly frag - geographical insight, this study also mentary knowledge. This is also valid improves our understanding of the bio - for basic faunistics (biodiversity, bio - diversity of Solenogastres even within a geography, etc.). Due to such incom - fairly well investigated biogeographical pleteness, all information - even if frag - region (cf. SALVINI -P LAWEN 1986, 1990).

SYSTEMATICS

Ordo PHOLIDOSKEPIA Salvini-Plawen, 1978

Solenogastres with a single layer supplemented by other solid scle - of adpressed and overlapping solid, rites; cuticle thin, no epidermal papi- scaly mantle sclerites, sometimes llae.

Family DONDERSIIDAE Simroth, 1893

The family is characterised by two cles (so-called type A in SALVINI - different types of mantle scales, by a PLAWEN , 1972, 1978), as well as by the monoserial radula provided with lack of respiratory organs. It includes paired, long denticles, by the foregut seven genera (cf. SALVINI -P LAWEN glandular organs as subepithelial folli - 1978).

Genus Nematomenia Simroth, 1893

Type species: Dondersia flavens Pruvot, 1890. Dondersia Hubrecht, 1888, partim; Myzomenia Simroth, 1893; Herpomenia Heath, 1911.

Definition : Solenogastres-Dondersi - radula, in part forming the unpaired idae with common atrio-buccal outlet for the paired foregut glandular opening; radula rudimentary: either organs; midgut without serial constric - monoserial radula with two pairs of tions; terminal sense organ present; sec - distally touching denticles (bifid-mono - ondary genital opening single, no copu - stichous type), or radula sheath without latory stylets.

Nematomenia banyulensis (Pruvot, 1890)

Dondersia banyulensis Pruvot; Myzomenia banyulensis (Pruvot) in Simroth 1893;

38 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

Diagnosis : Body distinctly red, elon - als comes from the campaign FAUNA gate and slender, up to 30 mm, middor - IBERICA III (PB 923-0121), station 186 A, sal scales forming a longitudianl crest; from off Cabo Cros in front of Punta na main type of scales short and wide, dis - Foradada/NE-Mallorca (39 ° 47.64’-39 ° tally pointed, proximally in part 49.66’ N, 2 ° 40.78’-2 ° 38.71’ E) at 59-61 m notched; mid-foregut forming a protrusi - from a bottom also characterised by the ble cone, without radula, radula sheath presence of Hydrozoa-Sertulariidae. This forming the single outlet of paired glan - latter record interbridges the known oc - dular organs and, by elongation, open - currence from the Gulf of Naples and the ing at the tip of the cone, posterior Côte Vermeille (Banyuls). foregut curving anteriorly to open pre- One of the Malta animals (3.6 mm) cerebrally into frontal midgut; no papil - and the larger individual of the Mal - lated dorsal foregut gland; musculus lorca specimens (preserved only 3.2 mm longitudinalis distinctly separated. long, 0.5 mm high and 0.4 mm wide) Spawning ducts fused throughout, axi - were serially cross sectioned (semithin ally with one pair of receptacula seminis. ribbons of 2 µm with glassknife); they Remarks : This well-known species show all typical characters of N. banyu - (up to 30 mm in length) is recorded lensis (particularly curved foregut with along the European coasts with wide cone, etc.). Although the Mallorca gaps from off Dalmatia/Croatia to the animal (deposited in the Mus. Nacional Trondheimsfjord/Norway (P RUVOT Cienc. Nat., Madrid, mol. no. 15.02/15) 1891, N IERSTRASZ AND STORK 1940, contained eggs of Ø 80-100 µm and SALVINI -P LAWEN 1997, H ANDL AND sperm, the receptacula seminis were not SALVINI -P LAWEN 2001). There is a recent yet differentiated. As PRUVOT (1891: 716) finding of several 3-5 mm long, red spec - indicates that young individuals are imens by C. Mifsud (26.8.2002) from off pale reddish or orange, the distinct red Ras il-Wahx/NW-Malta (ca.35 o57´N, colour of both the small Mallorca 14 o19´E) at 120-140 m, and another animals (maximum size of only 3.5 mm) record (25.6.1994) of two small individu - is of interest.

Genus Micromenia Leloup, 1948 Rupertomenia Schwabl, 1955

Type species: Micromenia simplex Leloup, 1848.

Definition : Solenogastres-Dondersi - (bifid-monostichous type); midgut idae with atrial sense organ (vestibu - without serial constrictions; terminal lum) and mouth separate; monoserial sense organ (s) present; secondary radula with one pair of lateral, curved genital opening single, no copulatory denticles touching each other distally stylets.

Micromenia subrubra spec. nov.

Holotype : NW-Malta, off Ras il-Wahx, 35 o57´N, 14 o19´E, yellow mud and sand at 140 m (Sept. 1996); spicules and section series (cs 2 µm) on slides: Naturhist. Mus. Wien (NHMW), Moll. IVN 1002446. Paratype 1 : NW-Malta, off Ras il-Pellegrin, about 35 o55’N, 14 o19’E, 120 m (April 1994); spicules and section series (cs 2 µm) on slides: Nat. Hist. Mus. London, Rg.no. 20020531. Paratype 2 : NW-Malta, off Delli, grey mud at 140 m (June 1999); whole animal, 5 mm long (Fig. 10), preserved in ethanol: Naturhist. Mus. Wien (NHMW), Moll. IVN 102447. Derivatio nominis : Latin subrubrus = not very bright red, reddish.

39 Iberus , 21 (2), 2003

Diagnosis : Body reddish, to 5 mm x very slender shovel- to trowel-like 0.5 mm in size (stretched in life up to 7 scales 55-110 µm long (handle 12-20 µm mm), dorso-posterior body end gener - long) and 7-15 µm wide; b) slightly ally elongated. Calcareous mantle scle - curved solid needles with indistinct rites of two types: slender shovel-like handle, 80-110 µm long x 4-6 µm wide; scales and slightly curved solid needles. both types may extend beyond the Anteriorly concentrated subepithelial general body contour. glands opening into dorsal pharyngeal Foot and mantle cavity : Pedal ciliary pouch; paired ventral foregut glandular pit flat and wide (125 µm), densely cili - organs with single opening; midgut ated, without folds or ridges. Foot with short rostral caecum. With one pair formed by posterior narrowing of the cil - of receptacula seminis and vesiculae iated epithelium, changing along its seminales. Mantle cavity extending as a course between a flattened ridge (25 µm ventrally open gutter onto the elongated wide) with centrally high cells and a real dorso-posterior body portion, ventro- fold. It does not enter the mantle cavity. rostrally with pouch; 2-4 dorsoterminal Pedal gland voluminous with large sense organs (Figs 1-4, 10, 12). follicles at both sides in the anterior Material and methods : Several speci - body. Sole glands along pedal groove mens had been collected by Constantine small, scattered, of same histological Mifsud (Malta) in April,June/July 1994, quality as pedal glands. June 1995, August, Sept. and Nov. 1996, Mantle cavity as an elongated, ven - June 1999 and May 2001 from muddy trally open gutter extending along entire bottoms off Western Malta in the area dorso-posterior beak-like body portion, off Ras il-Pellegrin (between the Gnejna densely ciliated without respiratory for - and Fomm ir-Rih bays), about 35 o55’N, mations. At the beginning of this beak- 14 o19’E, at 120-160 m (see MIFSUD , 1996), like portion the ventroterminal body and off cape Ras il-Wahx, about wall including “abdominal” spicules is 35 o57´N, 14 o19´E, at 140 m. curved dorso-anteriorly to form a wide Ribbons of semithin serial sections dorsally open gutter facing the gutter of (cs 2 µm) of several specimens have the mantle “cavity”. This entire internal been made with glassknifes and stained space is rostrally three-partitioned (Fig. with Richardson’s solution. 4): dorsal epithelium closing up as rectal External appearance : The slender opening (anus); central portion closing animals are generally 2.5-5 mm in length up to represent the short outlet of the vo - (Fig. 10), but when stretched in life may luminous spawning duct; the ventral even reach a length of up to 7 mm. They portion becoming a rostral, wide and are fairly susceptible to mechanical effects flattened pouch which - at least dorsally and easily damaged through sampling - appears to be lined by mantle epithe - treatment. The animals exhibit in life a dis - lium (with cuticle-like substance and tinct, not very intensive reddish colour embedded small sclerites). More throughout, ranging from pink to red (see frontally this pouch either (holotype) Fig. 4 in MIFSUD 1996). The hind end in continues ventrally in a fairly circular adults shows a beak-like extension of the blind sack (Figs. 4, 12), or shows a mid - dorso-posterior body (Fig. 10); in smaller ventral ridge, implying distinct symme - (juvenile or sub-mature) individuals (up try of the wide pouch; the latter condi - to 3 mm in length) the posterior body in tion (paratype 1) extends anteriorly until life may be swollen and appear to be still just below the end of the pericardium. devoid of the dorso-posterior body elon - Musculature : Body wall musculature gation. The mantle sclerites are generally distinct but not very compact, its fibres adjoining and give the body surface a showing a loose arrangement enclosing somewhat shiny appearance; the mid - lacunae. No lateroventral reinforcement dorsal scales may form a low crest. of longitudinal fibres. The regular Mantle : Cuticle 7-15 µm. Calcareous dorsoventral bundles are weak and run mantle sclerites of two types (Fig. 1): a) peripherically, only occasionally causing

40 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

2 ce go

gl ph mg as du

vg rs as 1

pi fo

50 µm 3 30 µm

10 µm

co hg go vs pc pd so

sd mg sr mc

fo 100 µm Figures 1-4. Micromenia subrubra spec.nov. 1: mantle sclerites; 2: organisation of the anterior body; 3: one radula tooth/plate; 4: organisation of the posterior body. Abbreviations, as: atrial sense organ; ce: cerebral ganglion; co: suprarectal commissure; du: outlet of ventral foregut glandu - lar organs (type A); fo: pedal fold (foot); gl: follicles of glands; go: gonad; hg: hindgut (rectum); mc: mantle cavity; mg: midgut; mo: mouth opening; pc: pericardium; pd: pericardioduct; ph: pharynx; pi: pedal pit; rs: radula sheath; sd: spawning duct; so: terminal sense organ; sr: receptacu - lum seminis; vg: (first) ventral ganglion; vs: vesicula seminalis. Figuras 1-4. Micromenia subrubra spec.nov. 1: Escleritas del manto; 2: organización de la parte ante - rior del cuerpo; 3: diente radular; 4: organización de la parte posterior del cuerpo. Abreviaturas, as: órgano sensorial atrial; ce: ganglio cerebral; co: comisura suprarrectal; du: abertura de los órganos diges - tivos ventrales anteriores (tipo A); fo: pie; gl: grupos de glándulas; go: gónada; hg: recto; mc: cavidad del manto; mg: tubo digestivo; mo: abertura bucal; pc: pericardio; pd: pericardioducto; ph: faringe; pi: foseta pedal; rs: rádula; sd: conducto de la puesta; so: organo sensorial terminal; sr: receptáculo seminal; vg: (primer) ganglio ventral; vs: vesícula seminal.

41 Iberus , 21 (2), 2003

constrictions of the midgut. At the begin - sense organs at the posterior elongation ning of the pericardium, the in - of the body (Fig. 4). ner/upper pair of dorsoventral bundles Alimentary tract : Mouth opening fuses with the peri-pericardial muscula - wide, separate from the atrium, leading ture. into a voluminous (or but longitudinally Sensory system : Cerebral ganglion folded) foregut with a dorsal enlarge - (110-125 µm wide, 75-80 µm high, 70 µm ment below the cerebral ganglion. This long) with separate connectives, the pouch receives frontally subepithelial buccal ones first and very close to the follicles of glandular cells (Fig. 2) ventral connectives. Four laterofrontal without forming a papilla. Behind pairs of medullary roots of cerebral pouch, foregut with some distinct circu - nerves (holotype), a ventro-lateral, a lar musculature. lateral and two subsequent dorsolateral Radula (Fig. 3) consists of monoser - ones; the lateral and dorsolateral roots ial teeth or plates (20 µm wide), each connect at each side to an adjacent basal with a curved denticle laterally (up to 20 ganglion; this latter gives rise to only µm long), both which are very close two (rather than three) nerves which medially and touch distally. Ventral lead together with the separate ventro - foregut glandular organs present as lateral cerebral nerve to the atrial region. wide ducts or ampullae (Fig. 2) with All these (six) nerves are medullary. large subepithelial follicles filling the Lateral ganglia elongate (55 µm x Ø space to the midgut; wide ducts fuse to 30 µm) and adjacent to the cerebral open by a single outlet ventral of the ganglia. Ventral ganglia voluminous (Ø anterior radula. 60 x 45 µm), interconnected by two com - Foregut in radular region with missures, followed by another pair of dorsal and lateral coating of small ventral ganglia with their commissure, subepithelial foregut glands adjacent to all posterior to the ciliated pedal pit strengthened circular musculature. (Fig. 2). Buccal ganglia (Ø up to 45 x 25 Postradular foregut opening axially µm) posterio-lateral of the radula sheath without sphincter into the (surround - between the follicles of the foregut glan - ing) midgut. Frontal midgut caecum dular organs, interconnected by an short. Midgut, depending on the indi - exceptionally long commissure dor - vidual, at a more or less distinct dis - soterminally of the sheath (150 µm tance from the body wall. Regionally when relaxed in the here 300 µm wide showing irregular bulges, but no true body, 60 µm when contracted and serial constrictions due to the dorsoven - curved). tral musculature and not forming Suprarectal commissure overlying regular lateroventral pouches. Middor - rectum just below end of the peri - sal ciliary tract present. In two speci - cardium (Fig. 4). The lateral cords con - mens small nematocysts were embed - tinue medullarly into the dorsoposterior ded in the midgut epithelium. body extension and form two additional Circulatory system : Atrium of heart thick commissures. forming a spacious invagination of the Atrial sense organ clearly separated pericardial roof, being free in its anteri - from mouth. A distinct pre-atrial, cili - ormost portion only and interconnected ated pit is formed which leads into the with the ventricle by one distinct voluminous atrium. Atrial ciliary tract opening. Ventricle for half or two-thirds running at the periphery of the opening its entire extension as an invagination of only, frontally continuous with the pre- anterior pericardium. atrial pit. No dorsal ciliation. Cavity Body spaces (pseudocoel) between itself with several stoutish papillae, the organs in part filled by distinct mes - most being elaborated as pairs. enchyme as well as blood cells. The There are two (holotype) to four latter consisting of round cells (Ø 2-5 (paratype 1) subsequent dorso-terminal µm) with in part densely granulated contents and well visible nucleus, and of

42 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

more irregular, vacuolised cells (Ø 3-7 muscle bundles. Such a condition, µm). however, could perhaps be correlated Gonopericardial system : The two with body size and would then not rep - gonads distincly separated throughout, resent a good generic character. Apart containing eggs of at most 40 µm in from this, note the closer similarities diameter. Terminal portion of the gonads with respect to the shovel- to trowel-like in fully mature animals serves as a volu - scales in the present species and in Don - minous sperm bag, then being ventrally dersia festiva Hubrecht, 1888, as well as continuous with the two short and wide in Heathia porosa Heath, 1911 (see SCHEL - gonopericardioducts, which are ciliated TEMA , 1998a). There is also a remarkable throughout. Ducts open dorsally into the multiplication of dorsoterminal sense pericardium, ciliation continuing as a organs in some Dondersia species: two in paired, wide lateral tract throughout D. festiva and D. indica Stork, 1941, three pericardium and entering pericardiod - in D. annulata Nierstrasz, 1902, and ucts. Pericardioducts emerging termino- eleven in D. californica Heath, 1911. laterally, each elaborating in its subse - With respect to the mentioned elabo - quent curve towards anterior an elongate ration of the midgut, the species in ques - and wound, anteriorly directed vesicula tion belongs to Micromenia . At present, seminis (Fig. 4). Ciliated pericardioducts two Micromenia species are known, i.e. open rostrally from laterodorsal into the M. simplex Leloup and M. fodiens respective spawning duct. (S CHWABL , 1955). Besides the known Both spawning ducts connected ante - geographic occurrence off Spitzbergen, riorly by a curved duct (stalk) with a M. simplex differs from the specimens at voluminous receptaculum seminis (Fig. hand by several dominant characters, 4). After a short length, both glandular e.g. the lack of the dorsoposterior body spawning ducts open anterio-laterally elongation, the differentiation of scat - into a voluminous continuation showing tered pharyngeal glands, the paired a rostro-median pouch between the opening of the ventral foregut glandular openings and being provided with a dis - organs and the unpaired spawning duct tinctly lower, ciliated epithelium. This (LELOUP , 1948; SALVINI -P LAWEN , 1972). subsequently single spawning duct soon M. fodiens is known from SW Sweden widens laterally and becomes dorsally as and from Norway in the area off Bergen well as ventrally lined by a high glandu - (SALVINI -P LAWEN , 1988); new evidence lar epithelium and provided with some comes from the Skagerrak (two localities, musculature. It opens by means of a 70-80 m) and the Trondheimsfjord short and simply-lined, central outlet, (several localities, 185-530 m) (pers. surrounded by musculature, into the comm. C. Handl, Vienna). M. fodiens “mantle cavity” (see above). differs from the present animals by the Discussion : It should be mentioned whitish body colour and the lack of the that two sub-mature animals showed an dorsoposterior body elongation as well atrial sense organ without papillae, and as of a pedal fold, the shape of the scales, it cannot be evaluated whether this the rudimentary atrial sense organ refers to the sub-mature status or without papillae, and also by details of reflects a teratological condition. the gonopericardial system ( SCHWABL The characteristic radula classifies 1955, SALVINI -P LAWEN 1972, 1988). the present animals within the Donder - M. subrubra spec.nov. is thus well- siidae in the closer relationship of Don - separated and its finding enlarges the dersia Hubrecht, 1888, itself (see SALVINI - biodiversity of Micromenia by a Mediter - PLAWEN , 1978) and of Micromenia . As ranean species. With respect to the body already pointed out earlier ( SALVINI - colour, together with Nematomenia banyu - PLAWEN , 1972: 218), the genus Microme - lensis (above) and the enigmatic Ne - nia differs from Dondersia by the absence matomenia (?) corallophila (K OWALEVSKY , of serial midgut constrictions due to the 1881) recorded upon Corallium rubrum peripherical course of the dorsoventral

43 Iberus , 21 (2), 2003

(L.) off La Calle/Algeria (cf. SALVINI - The family is characterised by the PLAWEN 1997), M. subrubra is the third nail-shaped type of mantle sclerites, “red Solenogastre” in the region. by a monoserial radula of serrate Family MACELLOMENIIDAE Salvini- plates, by the foregut glandular Plawen, 1978 organs as subepithelial follicles (so- called type A in SALVINI -P LAWEN , 1972, 1978), as well as by the presence of respi - ratory organs; at present it includes one genus only (cf. SALVINI -P LAWEN , 1978). Genus Macellomenia Simroth, 1893

Type species: Paramenia palifera Pruvot, 1890. Definition : Solenogastres-Macel - Paramenia Pruvot, 1890, partim [non Brauer lomeniidae with solid acicular sclerites and Bergenstam, 1889] with enlarged basal plate; paired ventral foregut glandular organs (type

A) with distally single outleading duct; terminal sense organ present; secondary genital opening unpaired; no copulatory stylets. Macellomenia adenota spec. nov.

Material : A single specimen 1.65 mm long and 0.75 mm across was collected in May 1986 from the Strait of Gibraltar, off Punta Almina (North of Ceuta: 35 o54.1’N, 0 o16.5’W; 25-40 m). After exami - nation of the mantle cover, ribbons of semithin serial sections (somewhat oblique cs 2 µm) were made with a glassknife and stained with haematoxyline-eosine. Holotype : Mus.Nat.Hist.Nat. (Malacologie), Paris; section series

Derivatio nominis : Greek adén = gland, Latin cells. Mantle cuticle thin, about 15 µm -otus = provided with; referring to the paired (13-20 µm). pre-pallial “abdominal gland” in addition to Rear of body with mantle cavity not the foregut glands. retained. With pre-pallial ventral mantle Diagnosis : Body less than 2 mm long; invagination with opening of a paired, mantle sclerites with spine slightly slender pouch, each including a bundle curved and up to 125 µm long, not form - of at least 12 slender spicules or spines ing a crest; atrial sense organ (vestibu - (abdominal spicula). In addition, a lum) and mouth opening separate; paired short tube also opens aside the radula plates curved with seven denti - end of the foot lateral in the groove of cles, the median one most promenent; the mantle invagination; it is elaborated midgut with paired rostral caecum, with - just anterio-dorsal of each spicule out regular lateral constrictions; with pouch, provided with an epithelium of paired “abdominal gland” and paired ab - well elaborated glandular cells and sur - dominal spicules, all opening into a pre- rounded by musculature (“abdominal pallial mantle invagination (Figs 5, 6, 16). gland”, Fig. 16). Description : Characteristic solid man - Pedal pit of foot simple, receiving tle sclerites (Figs. 5a, b) with a 70-100 the outlets of the pedal gland follicles. µm long, slightly curved spine and an The single pedal fold soon flattens to a oblique basal plate (20-25 µm x 12-15 wide ciliated ridge ending with mantle µm) reinforced at the free proximal rim. invagination. Sole glands along groove Some sclerites embedded in epidermis present. which includes several larger gland Body wall musculature without par - ticular ventral reinforcement of the lon -

44 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

100 µm go

bw 20 µm ca a mg

b bu a ce gl

5 as 6 fo Figures 5, 6. Macellomenia adenota spec.nov. 5: mantle sclerites from lateral (a) and frontal (b), and one radula plate; 6: organisation of the anterior body. Abbreviations, as: atrial sense organ; bu: buccal ganglion; bw: body wall (mantle and musculature); ca: midgut caecum; ce: cerebral gan - glion; fo: pedal fold (foot); gl: ventral foregut glandular organ; go: gonad; mg: midgut. Figuras 5, 6. Macellomenia adenota spec.nov. 5: escleritas del manto en vista lateral (a) y frontal (b), y diente radular; 6: organización de la parte anterior del cuerpo. Abreviaturas, as: órganos sensorial atrial; bu: ganglio bucal; bw: pared del cuerpo (manto y musculatura); ca: ciego digestivo; ce: ganglio cerebral; fo: pie; gl: órgano glandular digestivo ventral; go: gónada; mg: tubo digestivo.

gitudinal layer. Serial dorsoventral lateroventrally of the midgut and empty - bundles weak, running fairly close to ing at each side into short duct; both body wall, not constricting midgut. ducts uniting from lateral to a median Preoral atrial sense organ ending as outlet with circular musculature. Duct blind sack (Fig. 6), with few single, running below radula sheath and then stoutish papillae. Alimentary canal with below free radula to open beneath ante - mouth opening separate from atrium, riormost plate of protruded radula. leading into a short foregut. Animal Foregut opening into midgut above with somewhat protruded radula appa - beginning radula, midgut giving rise ratus, foregut forming a posterior pouch from this area to a paired rostral caecum above radula sheath as well as a flat with high epithelium (30-120 µm) equal blind sack extending rostrally over the to that of midgut. Midgut with some cerebral ganglion. Plates of monoserial nematocysts. radula only 25 µm wide and curved; Nervous system with single cerebral with seven denticles, the median one ganglion (110 µm wide, 40 µm high, 35 distinctly being strongest (Fig. 5). No µm long), connectives of body cords particular radula support. emerging separately. Buccal ganglia (Ø Ventral foregut glandular organs, 25 µm) aside radula sheath (Fig. 6), their each consisting of a densely packed commissure over sheath. Ventral ganglia bunch of subepithelial follicles extending (Ø 65 x 35 µm) adjacent to pedal pit.

45 Iberus , 21 (2), 2003

Animal mature, paired gonad with organ of the present specimen are not relatively large eggs (Ø up to 110 µm). known, this animal clearly represents a Other organs of gonopericardial system proper species, Macellomenia adenota (pericardium, spawning ducts, etc.) and spec. nov.. An association of abdominal mantle cavity not retained. spicula with a paired gland has been Discussion : Within Macellomeniidae, reported also in Squamatoherpia tricuspi - only two species of Macellomenia have data (B ÜCHINGER AND HANDL , 1996), been described so far, viz. M. palifera though in different mutual arrange - (Pruvot, 1890) and M. aciculata Schel - ment. The histology of the present tema, 1999, both provided with a similar, “abdominal glands” looks similar to remarkable mantle cover of solid acicu - that of spawning ducts; as no characters lar spicules with enlarged basal plate. of the pericardium and mantle cavity The present specimen fits well into that are known, the glands could be the frame, but exhibits specific differences. anlagen of those organs. If so, however, M. aciculata possesses radula plates with the spawning ducts would represent five equal denticles, the mouth opens at fairly unusual, lateral organs with the back of the atrial sense organ and medial opening into a pre-pallial mantle there is a lack of abdominal spicules invagination. The presence or absence of (SCHELTEMA 1999). The present specimen a terminal sense organ, as well as the coincides with the geographically closer common ( M. aciculata ; M. palifera ?) or type species M. palifera by the radula separated atrial and buccal openings plates with seven denticles and by the (M. adenota ) are judged to be generic presence of invaginated pouches for ab - characters ( SALVINI -P LAWEN , 1967b, dominal spicules ( PRUVOT , 1891: 790- 1978); due to the currently limited 791). There are specific differences how - insight in species organisation and ever: (a) Curved radula plates with a dis - species diversity of Macellomeniidae, tinctly prominent median denticle; (b) however, no reclassification is proposed paired midgut caecum (not present in M. herein. palifera ; PRUVOT 1891: 790); (c) the paired No accurate evaluation is possible “abdominal gland” (see below) empty - with regard to the Macellomenia speci - ing into the mantle invagination close in mens reported by Caudwell et al. (1995) front of the abdominal spicules; (d) body from the Irish Sea at 80 m and 120 m. In length (though mature, less than 2 mm; view of the present species from the M. palifera = 4-8 mm, Pruvot 1891: 727) Strait of Gibraltar and of M. aciculata and lack of a middorsal crest of spicules from 50 o N, 13 o W, the geographical dis - (PRUVOT , 1891: 727 and Fig. 4). Most tribution of each Macellomenia species probably (e), also in M. palifera the appears to be limited. This is in contrast mouth opening is located within the pre - to an earlier estimation (Salvini-Plawen, oral atrium. 1997) and speaks against a conspeci - Though the gonopericardial system, ficity of the Irish specimens with the the mantle cavity and the terminal sense Mediterranean M. palifera from the Côte

Vermeille. However, as already sur - animals can clear up the conspecificity mised (Salvini-Plawen 1997: 44), only an issue. anatomical investigation of the Irish Family LEPIDOMENIIDAE Pruvot,

1902 The family is characterised by one type of scaly mantle sclerites, by a distichous radula, by the foregut glandular organs as subepithelial follicles (so-called type A in

46 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

SALVINI -P LAWEN , 1972, 1978), as well as includes at present three genera (cf. by the lack of respiratory organs; it SALVINI -P LAWEN , 1978, 1988). Genus Tegulaherpia Salvini-Plawen,

1983

Type species: Tegulaherpia stimulosa Salvini-Plawen, 1983. Definition : Solenogastres-Lepidomeniidae with atrial sense organ (vestibulum) and mouth opening separate; terminal sense organ present; secondary genital opening unpaired; with copulatory stylets; no respiratory organs.

Tegulaherpia (?) spec. traceable. Gut containing several nema - tocysts, among them stenoteles, of a Material : A single specimen was collected by hydrozoan food. Diego Moreno (Cabo de Gata/Almería) from Discussion : The mantle scales, the sand below stones at Punta del Esparto nearby distinctly separate atrial sense organ Los Escullos, Cabo de Gata (Southeast Spain, » and mouth, and the distichous radula fit o o 36 50’N, 02 03’W) at 1 m depth only. After well within the characters of the genus examination of the mantle scales, ribbons of Tegulaherpia . Other characters, however, semithin serial sections (cs 2 µm) were made particularly the foregut glands and the with a glassknife and stained by Richardson’s copulatory stylets, could not be verified solution. The slides (mantle scales and series to confirm the generic classification. The section) are deposited in the Mus. Nacional shape and size of the scales (23 x 18 µm), Cienc. Nat., Madrid, mol. no. 15.02/14. and the radula (with four median denti - Description (Fig. 7): Specimen of 1.25 cles per tooth) do not coincide with the mm length and 0.35 mm across with an two known European Tegulaherpia evenly rounded body (Fig. 7 A), not yet species (cf. SALVINI -P LAWEN , 1988, 1997). mature, though developing eggs visible. No specific relationship can therefore be Of whitish colour and smooth surface hypothesised. The Adriatic T. stimulosa with small, densely adjoining and Salvini-Plawen, 1983 possesses 30-40 µm strongly overlapping, delicate scales x 20-25 µm sized scales and 4-5 radula measuring 23 x 18 µm (Fig. 7 C) tightly denticles; the geographically overlap - adjacent. Atrial opening with anterior ping, West-Mediterranean and NE- stereocilia (“bristles”), mouth and foot Atlantic T. myodoryata Salvini-Plawen, well visible in life (Fig. 7 A). 1988 (= T. celtica Caudwell et al., 1995) Unfortunately, the animal was very shows somewhat larger scales, 30-45 µm poorly preserved (partly in histolytic x 20-30 µm, and 4-5 radula denticles state) and only a few characters can be (SALVINI -P LAWEN , 1988; HANDL AND verified. Mouth opening distinctly sepa - SALVINI -P LAWEN , 2001). Fig. 7 D shows a rate from the atrial sense organ and scale of T. myodoryata from the most leading into a fairly straight foregut sur - eastern record off Malta (see MIFSUD , rounded by strong longitudinal muscu - 1996: Fig. 3) for comparison. Most spe - lature. Distichous radula consisting of cific differences between both known paired, erect teeth with symphysis, each species, however, concern the arrange - provided with a distal hook and four ment of the copulatory stylet apparatus median denticles (Fig. 7 B). Foregut and the outlet of the (fused) spawning glandular organs not traceable. Single duct ( SALVINI -P LAWEN , 1988); no com - cerebral ganglion above the mouth (90 parison of the present animal can there - µm wide, 60 µm high, 45 µm long) gives fore be made. According to the mantle rise to the connectives separately. Apart scales, the specimen appears to repre - from the gut, no organ of the posterior sent a species proper. body (spawning ducts, etc.) were clearly

47 Iberus , 21 (2), 2003

The habitat (sand) could also point 1985; G ARCIA -Á LVAREZ , U RGORRI AND to Meiomeniidae which have mesop - CRISTOBO , 2000b). sammic species; yet, these are charac - Apart from the possible presence of terised by mantle sclerites of two or an independent, third Tegulaherpia three different kinds ( SALVINI -P LAWEN , species, this finding is likewise of inter -

est as the shallowest record of a 1978 solenogastre (one meter depth only). Solenogastres with acicular, gener - Due to the need of calmer waters for cil - ally hollow mantle spicules, cuticle iary gliding, Solenogastres species are mostly thick, with epidermal papillae. generally very rare on substrata shal - Remarks : As some findings indicate lower than about 50 meters, including (SALVINI -P LAWEN , 1978; S CHELTEMA AND Urgorria monoplicata (below) or the KUZIRIAN , 1991; H ANDL AND SALVINI - mesopsammic representatives (cf. GAR - PLAWEN , 2002), the main character of this CÍA -Á LVAREZ ET AL ., 2000b). However, taxon - the hollow acicular spicules - exceptions such as Epimenia arabica strictly taken may be polyphyletic (not Salvini-Plawen and Benayahu, 1991, a supported, however, by computerised large-sized species (13-21 cm) living hid - cladograms; cf. SALVINI -P LAWEN , 2003). den in Alcyonaria-colonies at 2-5 meters Investigations have also called attention depth, occur. on differences in the developmental Ordo CAVIBELONIA Salvini-Plawen, arrangement of the spicules at the generic level, e.g. in Pararrhopaliidae (cf. Table I) or in Simrothiellidae: they are either (1) in a radial or (2) in a tangential alignment ( HOFF - MAN 1949). The latter may be produced (2a) in a single, obliquely disposed layer, or (2b) they are arranged in two or more fairly rectangularly intercrossing layers of low angle and almost embedded within the cuticle (and also termed “skeletal”; SCHELTEMA , 1999, SCHELTEMA AND SCHANDER , 2000). Another criterion exists with respect to the enclosed cavity: the spicules may be either thick-walled or thin-walled. Spicules may be distally hooked (or barbed), asymmetrically flat - Plawen, 1972 tened and serrate, or asymmetrically axe- like enlarged (termed “captate” by (Parameniidae Simroth, 1893; Paramenidae ARNOVSKY , 2000). Pruvot, 1902; Perimeniidae Nierstrasz, Family PARARRHOPALIIDAE Salvini- 1909*); Pruvotiniidae Heath, 1911; Pruvo - tinidae Scheltema, 1998)

* As NIERSTRASZ (1909: 291-292) consciously introduced a synonymy ( Perimenia instead of Pru - votina ), his family “Perimeniidae” cannot be accepted as valid. The family is characterised by a distichous radula, by the foregut glandular organs generally as subepithelial follicles (so-called type A in SALVINI -P LAWEN 1972, 1978), as well as by the additional presence of hooked mantle spicules and/or of a middorsal papillous pharyngeal gland and/or of Genus Eleutheromenia Salvini- respiratory organs ( SALVINI -P LAWEN , Plawen, 1967 1978, GARCÍA -Á LVAREZ , S ALVINI -P LAWEN AND URGORRI , 2001); it includes 15 genera (Table I).

48 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

as mo fo

C D

20 µm

Figure 7. A-C: Tegulaherpia (?) sp. A: living animal from ventrolateral (sketch by Diego Moreno, Cabo de Gata); B: one pair of radula teeth with symphysis; C: one mantle scale. D: Mantle scale of Tegulaherpia myodoryata from off Malta. Abbreviations, as: atrial sense organ; mo: mouth opening; fo: pedal fold (foot). Figure 7. A-C: Tegulaherpia (?) sp. A: animal vivl en vista ventrolateral (esquema de Diego Moreno, Cabo de Gata); B: par de dientes radulares con sínfisis; C: escala del manto. D: Escala del manto de Tegulaherpia myodoryata de Malta. Abreviaturas, as: órgano sensorial atrial; mo: abertura bucal; fo: pie.

(Paramenia Pruvot, 1890, partim [non Brauer and Bergenstamm, 1889]; Pruvotina Cockerell, 1903, partim; Perimenia Nierstrasz, 1909, partim) Type species: Paramenia sierra Pruvot, 1890; Costa Brava. Definition (amended) : Solenogastres with hollow spicules in more than one layer, also including hooked ones; with common atrio-buccal opening; radula present, ventral foregut glandular organs subepithelial with paired outlet (type A); no dorsal papillous foregut gland; midgut with serial ventro-lateral constrictions; with dorsoterminal sense organ, with respiratory organs; unpaired secondary genital opening; no receptacula seminis and no copulatory stylets. Eleutheromenia sierra (Pruvot, 1890) ries of 15 prominent lobes; cuticle mod - Paramenia sierra Pruvot, 1890 erately thick, no epidermal papillae; spicules upright, tangential and inter - Material : One specimen (preserved 11,5 mm crossed, as well as hooked, all hollow; long, with lobes up to 1,7 mm high) of typical elongate scales along the pedal groove. aspect and shape (Fig. 11) comes from the Skjörn Abdominal spicules in a paired bundle, Fjord north of Trondheim/Norway at 218 m each consisting of numerous hollow depth (collected 2.3.1992 by G. Steiner, Vienna). straight elements. Radula teeth with dis - Ribbons of semithin serial sections of this spec - tal hook, no median denticles; ventral imen (cs 2 µm) were made with glassknives and foregut glandular follicles with paired stained with toluidine-blue. duct, midgut with rostral caecum. Vesic - Type material no longer existent. The present ulae seminales present, no receptacula material (series sections on slides) is deposited in the Naturhist. Mus. Wien (NHMW), Moll. seminis; up to 28 gill folds. Costa Brava, IVN 102448. Bretagne, Irish Sea, Trondheim area; 40- Diagnosis : Body up to 12 mm x 2 mm 128 m (Figs. 8, 11, 15). with middorsal carina extended to a se - Body wall : Body marked by a mid - dorsal carina elaborated into three

49 Iberus , 21 (2), 2003

smaller and twelve subsequent promi - The mantle or pallial cavity holds at nent lobes (Fig. 11). In these bulges, cir - its posterior wall blunt gill folds (28 in cular musculature splits into a small PRUVOT , 1890, 1891). The hindgut opens subepithelial fraction (entering the frontally and, even more anteriorly, the bulge) and main fibres traversing the outlet of the spawnings ducts opens base of bulge, thus as usual delimiting ventrally. Between the end of the foot body cavity. Space between this split and the opening of the mantle cavity the musculature filled by mesenchyme and invaginated bundles of the abdominal large vacuole (gland) cells. Regions spicula are elaborated (Fig. 15). There between the lobes normally structured. are no copulatory stylets. Epidermis covered by a 25-30 µm Sensory system : Cerebral ganglion thick cuticle, locally reaching 50 µm. unpaired (240 µm wide, central Ø 130 Especially in the posterior body, big, µm) giving rise to connectives sepa - pluricellular epidermal glands, but no rately; two pairs of small ganglia imme - true epidermal papillae; only a few epi - diately adjacent to it, innervating the dermal protrusions scattered ventrally atrial region. Lateral body cords loosely at both sides of the posterior pedal provided, ventral ones more densely groove (mantle rims). provided with nuclei; in the posterior Mantle with three main types of body, cords are clearly medullary. In the hollow spicules (Fig. 8) in part extend - ventral system, ganglia with commis - ing beyond cuticle and thus resulting in sures fairly densely elaborated, without a somewhat rough surface. Spicule correspondance to lateroventral connec - types are (a) more or less straight ones tives. The (first) ventral ganglia (Ø 80 (130-350 µm), (b) similar type with a µm) showing two commissures; without harpoon-like indentation at the solid commissural sack. Buccal ganglia like - distal portion (up to 400 µm; see wise prominent (Ø 60 µm). “species incerta II” in SALVINI -P LAWEN , Suprarectal commissure 150 µm long 1978: 118-119 and Unciherpia in GARCÍA - (Ø 40 µm) and interconnecting the ÁLVAREZ ET AL ., 2001), and (c) somewhat ganglia posteriora superiora medullarly; bent spicules (up to 125 µm) with solid at least two pairs of posterior nerves distal portion forming a hook with knob originate there. at the turn. In addition, some very Atrial sense organ with stoutish slender acicular spicules and, sporadi - single or bifurcated papillae and bor - cally, ones with distal serration (d) dered by a horseshoe-shaped ciliary occur; along the pedal groove (e) elon - fold, the dorso-posterior incurvings gate scales (up to 80 x 13 µm). exclude the buccal groove continuous Behind foot, a pair of ventromedially with the mouth. directed invaginations of the body Region of the dorsoterminal sense epithelium, each embedded within organ (close to the body end, according ventral body wall musculature and to PRUVOT , 1891) in present animal housing a bundle of straight, 130 µm (or destroyed. more) long, hollow abdominal spicules Alimentary tract : Mouth opening in (Fig. 15). Epidermis as usual underlain the dorsoposterior area of the common by circular and longitudinal muscles; atrio-buccal cavity, connected with the only weak lateroventral reinforcement sensory region by a groove. Buccal of longitudinal musculature. space with high folds leading into the Foot and mantle cavity : The ciliated pharyngeal foregut; foregut with dis - pedal pit gives rise to a single longitudi - tinct pre-radular circular musculature nal fold which runs through the pedal and intercellularly opening, subepithe - groove. The foot ends, however, in front lial pharyngeal glands; without com - of the abdominal spicules, not entering pacted dorsal foregut gland (with the mantle cavity. The pedal gland is papilla). Radula typically distichous, voluminous, and the sole glands open each tooth (25-30 µm high) with a distal all over into the pedal fold and groove. hook; median denticles could not be dis -

50 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

a b

d c e

50 µm

Figure 8. Eleutheromenia sierra (Pruvot) from the Trondheim area, types of mantle sclerites. Figura 8. Eleutheromenia sierra (Pruvot) del área de Trondheim, tipos de escleritas del manto.

cerned in the sections. Radula support dial lumen. Atrium clearly paired and represented by an assemblage of muscu - fusing just before the axial transition into lar and connective tissue. Ventral ventricle. Two kinds of blood cells: foregut glandular organs as follicles round, homogeneous ones (Ø 10 µm) emptying at each side into distinct and oval to round, vacuolated or vari - opening lateroventrally of radula (type ously granulated cells (10-20 µm long). A in SALVINI -P LAWEN , 1972, 1978). Pericardioducts emerging posteri - Midgut with rostral caecum and con - orly, forming in their curve towards stricted only ventro-laterally by serial anterior short sacculations (vesiculae dorsoventral muscle bundles to form seminales) and opening laterodorsally pouches. No nematocysts were ob - into respective spawning duct. No served within the gut. Middorsal ciliary receptacula seminis present. Spawning tract widens to cover entire hindgut ducts voluminous, highly glandular, opening into mantle cavity above and and subdivided into two equal sections: behind unpaired spawning duct outlet. paired portion not axially continuous Gonopericardial system : Paired gonad with unpaired section, the latter extend - showing developing germ cells in the ing somewhat below the former, with posterior region within lateral sacks, the paired dorsoventral interconnection. most posterior pair representing vesicu - Unpaired section opening by means of lae seminales. Paired gonopericardial simple outlet ventrally to exterior; this ducts opening dorsofrontally into peri - opening representing the anterior-most cardium with a paired anterior begin - area of the mantle cavity opening. ning. Pericardium voluminous with Discussion : Though the present speci - paired lateral ciliary tract and containing men comes from Skjörn Fjord (Trond - mature eggs (Ø 140 µm or 150 x 130 µm); heim region), the type locality of Parame - probably due to such conditions, PRU - nia sierra (Pruvot) is off the Costa Brava VOT (1891) cosistently termed the peri - (Catalunia/Spain); for comparison with cardium as “sac ovigère”. Heart the description by Pruvot (1891), a full throughout as mediodorsal invagination, descriptive presentation of the new anteriorly very wide, then hanging by a finding was given here. The specimen double “mesenterium” into the pericar - from Norway exhibits an almost identi -

51 Iberus , 21 (2), 2003

cal organisation to E. sierra which (Cap Creus/Costa Brava) at 75-80 m, includes, for example, also the dorso- and a finding from off Roscoff/Bretagne frontal opening of the gonopericar- at about 40 m (Pruvot, 1897), several dioducts into the pericardium (P RUVOT , other records have been reported from 1891: Fig. 17). Some characters are not the Irish Sea (cf. SALVINI -P LAWEN , 1997). mentioned by Pruvot (such as, e.g. the Though without closer examination, posterior-most gonad serving as seminal due to their typical appearance (lobu - vesicles, or the subdivision of the spawn - lated keel), however, these latter speci - ing ducts); there appear to be, however, mens may likewise belong to E. sierra ; just three discrepancies. First, the mantle this is biogeographically supported by spicules are not exactly identical. Pruvot’s record from off Roscoff and by Second, in the region of the posterior the present specimen (Trondheim area). body drawn as a cross section by Paramenia sierra Pruvot was generically PRUVOT (1891: Fig. 61), Pruvot claims a transferred by SALVINI -P LAWEN (1967b) to “glande cloacale” (Fig. 61: y). Here, apart a new genus Eleutheromenia . A second from muscle fibres, numerous sole species, Pruvotina impexa THIELE (1913a), glands, the medullary ventral nerve after re-examination was generically sep - cords as well as two connected ganglia arated later as Labidoherpia impexa (Salvini- innervating the spawning ducts are Plawen, 1978). Most recently, SCHELTEMA present in the Norwegian specimen. (1998b) and SCHELTEMA AND SCHANDER Some of these structures could represent (2000) described two Eleutheromenia species Pruvot’s gland as no real glandular from the Bass Strait, South of Australia. organ is discernible; also the distance to According to the descriptions and a pre - the mantle cavity (“cloaca”) is too long liminary re-examination of specimens ( E. in both Pruvot’s animal and the present mimus from Slope Station 40, E. bassensis specimen to represent a pallial gland. from BSS-S 202; a full description of the A third and more essential point of dis - anatomies is in preparation by Cl. Handl, agreement of the new specimen with Para - Wien/Vienna, Austria), both these latter menia sierra appears due to PRUVOT ’s species differ markedly in several charac - (1891: 790) somewhat misleading decrip - ters from Eleutheromenia sierra (P RUVOT , tion of the “petits caecums” at the end of 1891 and above): the pedal groove, which he equalises with (1) They do possess copulatory “l’appareil spiculaire pénial de Proneome - stylets, in contrast to E. sierra (with nia vagans ” [= Pararrhopalia pruvoti abdominal spicules, see above); Simroth, 1893]. This equalisation led to the (2) The ventral foregut glandular (incorrect) definition of Paramenia sierra as organs are tubular with epithelial gland possessing copulatory stylets ( THIELE , cells (type C in SALVINI -P LAWEN 1972, 1913b, SALVINI -P LAWEN , 1967b). As Pruvot, 1978); however, describes correctly in detail (3) In both species a “ventral com - (PRUVOT , 1891: 790), P. sierra possesses missure sack” of unknown function is “une paire de petits caecums” (plural!)... present, similarily as in the gymnomeni - “plongés dans les muscles longitudineaux ids Genitoconia , Wirenia [= Aesthoherpia] ventraux, dans chacun desquels” he recog - and Gymnomenia (S ALVINI -P LAWEN , nised “un faisceau de spicules”. This is an 1967a, 1988, HASZPRUNAR , 1986, SCHEL - exact description of a paired bundle of TEMA , 1999); abdominal spicules, such as exists in the (4) The glandular anterio-ventral present individual (Fig. 15). portion of the pericardium (not in open The Norwegian specimen described communication with the mantle cavity) here is thus regarded as conspecific with - in connection with the pericardial Eleutheromenia sierra (Pruvot). glands - speculatively might represent Apart from the single, no longer part of some kind of excretory system. existent type specimen (11-12 mm x 2 With respect to the generic charac - mm) of the original description by PRU - ters among the family Pararrhopaliidae VOT (1890, 1891) from off Portaló Island (Table I), at least the above characters (1)

52 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

Table I. Generic characters in Pararrhopaliidae (see SALVINI -P LAWEN 1967b, 1978; GARCÍA - ÁLVAREZ ET AL ., 2001, GARCÍA -Á LVAREZ AND URGORRI , 2001). A: ventral foregut glandular organs with subepithelial follicles (type A); C: ventral foregut glandular organs epithelial (type C); dts: dorso-terminal sense organ; pphf: peri-pharyngeal ring of follicular glands; -: absent; +: present. Tabla I. Caracteres genéricos en Pararrhopaliidae (ver SALVINI -P LAWEN 1967b, 1978; GARCÍA - ÁLVAREZ ET AL ., 2001, GARCÍA -Á LVAREZ Y URGORRI , 2001). A: órganos glandulares digestivos ven - trales con folículos subepiteliales (tipo A); C: órganos glandulares digestivos ventrales epiteliales (tipo C); dts: órgano sensorial dorso-terminal; pphf: anillo perifaríngeo de glándulas foliculares; -: ausente; +: pre - sente. hooked dorsal ventral respiratory mouth copulatory radula cuticle dts spicules gland glands folds separate stylets Pruvotina + +A + - - + thick + Pararrhopalia + +A - + + + thick + Labidoherpia + + A +-+ + thick + Eleutheromenia +- A + - - + thick + Gephyroherpia +- A + + - + thick + Luitfriedia + - A + - - - thick + Lophomenia -+A ? + - + thick + Metameria -+A - + - + thick + Hypomenia -+A - + - + thick ? Halomenia --A + + - + thick + Forcepimenia --A ? +?+thin - Scheltemaia + - C + - + + thick + Unciherpia + - pphf +---thin + Uncimenia - (?) - pphf ++-- thin + Sialoherpia --pphf ?+? - thick +

and (2) concern the generic level. Apart from the different type of the foregut glandu - lar organs in both Australian species (see also Unciherpiinae in GARCÍA -Á LVAREZ ET AL ., 2001), copulatory stylets are only present in Labidoherpia Salvini-Plawen (with pa - pillous dorsal pharyngeal gland) and in Pararrhopalia Simroth (with papillous gland, mouth separate). Thus, both these Scheltemaia gen. nov. species, E. mimus and E. bassensis , do not fit into an existing genus and conse - Type species (with respect to the more accu - quently are transferred to a separate rate description): Eleutheromenia mimus genus Scheltemaia gen.nov. (see also the Scheltema and Schander, 2000; Bass Strait cladistic analysis in SALVINI -P LAWEN , (South Australia). 2003).

Definition : Solenogastres-Parar - each as tubes or sacks with epithelial rhopaliidae with hollow spicules includ - gland cells (type C in SALVINI -P LAWEN ing hooked ones; with common atrio- 1972, 1978); no dorsal papillous foregut buccal opening; radula distichous; gland; with “commissure sack” between paired ventral foregut glandular organs (first) ventral ganglia; with dorsotermi -

53 Iberus , 21 (2), 2003

go 100 µm

bw ca gl

mu ph ce

Figure 9. Urgorria monoplicata spec. nov. Organisation of the anterior body. Abbreviations, as: atrial sense organ; bw: body wall (mantle and musculature); ca: midgut caecum; ce: cerebral gan - glion; fo: pedal fold (foot); gl: ventral foregut glandular organ; go: gonad; mu: muscle bundle; ph: pharynx. Figura 9. Urgorria monoplicata spec. nov. Organización del cuerpo anterior. Abreviaturas, as: órgano sensorial atrial, bw: pared del cuerpo (manto y musculatura); ca: ciego digestivo; ce: ganglio cerebral; fo: pie; gl: órgano glandular digestivo ventral; go: gónada; mu: unión muscular; ph: faringe.

nal sense organ, with respiratory organs; unpaired secondary genital opening; with copulatory stylets; no recepta cula seminis. Two species known. Family RHOPALOMENIIDAE Salvini-Plawen, 1978

The family is characterised by a thick glandular organs subepithelial (type A) cuticle and hollow acicular spicules in and/or epithelial (type C; SALVINI - several layers, without hooked spicules; PLAWEN , 1972, 1978); no respiratory radula distichous or lacking; no papillate organs. It includes five genera ( GARCÍA - dorsal foregut gland, ventral foregut ÁLVAREZ AND SALVINI -P LAWEN , 2001).

Genus Urgorria García-Álvarez and Salvini-Plawen, 2001

Type species: Urgorria compostelana García-Álvarez and Salvini-Plawen, 2001; off northwestern Spain. Definition : Solenogastres-Rhopalo me niidae with epidermal papillae and hollow acicular spicules in several intercrossing layers; mouth opening within the atrium; without radula; paired foregut glandular organs epithelial (type C in SALVINI -P LAWEN 1972, 1978); dorso-terminal sense organ present; secondary genital opening unpaired, no copulatory stylets.

54 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

10 11

12 13

sd ce ph

po sc

Figure 10. Micromenia subrubra spec.nov. (paratype 2), preserved 5 mm specimen; note beak-like ex - tension of dorsal body end (below). Figure 11. Eleutheromenia sierra (Pruvot) from Trondheim area, preserved animal (11.5 mm long). Figure 12. Micromenia subrubra spec.nov., cross section through posterior body behind pericardium [hg: hindgut; po: anterior pouch of mantle cavity with separated anterio-ventral portion; sd: spawning duct] scale bar: 50 µm. Figure 13. Urgorria monoplicata spec.nov., cross section through mantle bridge (retracted) between atriobuccal opening and pedal pit with pre- pedal scales (sc) [ca: midgut caecum (paired); ce: cerebral ganglion; ph: pharynx] scale bar: 100 µm. Figura 10. Micromenia subrubra spec.nov. (paratipo 2), especimen fijado, 5 mm; nótese la extensión con forma de pico en la parte final (abajo). Figura 11. Eleutheromenia sierra (Pruvot) del área de Trondheim, animal fijado (11.5 mm). Figura 12. Micromenia subrubra spec.nov., sección del cuerpo posterior tras el pericardio [hg: intestino posterior, po: saco anterior de la cavidad del manto con porción separada antero-ventral, sd: conducto de puesta] escala: 50 µm. Figura 13. Urgorria monoplicata spec.nov., sección entre la abertura atriobucal y la foseta pedal con escalas pre-pedeales (sc) [ca: ciego digestivo, ce: ganglio cerebral, ph: faringe] escala: 100 µm.

55 Iberus , 21 (2), 2003

Urgorria monoplicata spec. nov. Mantle : Mantle producing a moder - ately thick cuticle only (40-50 µm) Material : A single specimen of 2.2 mm length without marked thickenings; epidermal (Ø 0.5 mm) with evenly rounded body end orig - papillae distally balloon-shaped. inates from off the Costa Brava (Girona/Spain), Spicules (average 100 µm long) acicular from the “Furrió de Tamariu”, sandy bottom and hollow, in tangential and intercross - in 35 m depth (collected 16.9.1990 by Luis ing layers; no hooked or distally serrate Dantart, Barcelona). spicules; along foot elongate scales After examination of the sclerites, ribbons of (about 40 µm). Mantle bridge between semithin serial sections (cs 2 µm) were made atrio-buccal opening and pedal pit like - with a glassknife and stained with RICHARD - wise with distinct scales (Fig. 13). SON’s solution. Foot and mantle cavity: Pedal pit The specimen (series sections on slides) is receiving outlets of the voluminous deposited as holotype in the Mus. Nacional Cienc. Nat., Madrid, mol. no.15.02/13. pedal gland follicles that extend at both Derivatio nominis : Greek monos = one, Latin sides in the anterior body. Ciliated plica = fold; referring to the single pedal fold. epithelium of pit not forming folds. At Diagnosis : Body 2.2 mm x 0.5 mm, end of pit a single, distinct fold is differ - with evenly rounded ends; cuticle fairly entiated, continuing until the pallial thin without keel formation; foot with cavity. Sole glands parallel internally the one single fold only until mantle cavity; foot. Mantle cavity representing a no radula or vestige of radula sheath, simple ciliated space receiving dorsome - ventral foregut glandular organs as very dially the rectum and medioventrally small sacks opening ventrolaterally, ter - the single outlet of the posteriorly fused minal foregut with two pairs of strong spawning ducts. There are neither respi - muscle bundles to lateral body wall; ratory organs nor accessory genital midgut with large rostral caecum, ros - organs. trally paired, and with regular constric - Musculature : Body wall musculature tions. Spawning ducts in their distal half not very prominent, longitudinal fused, with simple opening; one pair of portion showing an only moderately non-stalked, dorsoposterior receptacula elaborated ventral reinforcement. Simi - seminis. Figs 9, 13, 14. larly, the dorsoventral bundles are typi - cally differentiated, but not very strong. Their fairly medial course serially in dis -

(Right page) Figure 14. Urgorria monoplicata spec. nov., somewhat oblique cross section through region of terminal foregut [bu: right buccal ganglion; dv: dorsoventral muscle bundle; fo: pedal fold (foot); gl: left foregut gland; mg: midgut; mu: musculature forming bundles; nv: medullary ventral nerve cord; pg: (portion of) pedal gland; ph: pharynx; sg: sole gland], scale bar: 30 µm. Figure 15. Eleutheromenia sierra (Pruvot) from Trondheim area, cross section through pre-pallial (post-pedal) region with abdominal spicules (sp) [sd: spawning duct], scale bar: 50 µm. Figure 16. Macellomena adenota spec. nov., somewhat oblique cross section through pre-pallial (post-pedal) mantle invagination (mi) with “abdominal gland” (ag) just before opening, and with opening of pouch of abdominal spicules (sp) [mg: midgut], scale bar: 30 µm. (Página derecha) Figura 14. Urgorria monoplicata spec. nov. Sección oblicua a la altura de la región terminal del digestivo anterior [bu: ganglio bucal derecho; dv: musculatura dorsoventral; fo: pie; gl: glándula digestiva izquierda; mg: intestino medio; mu: unión muscular terminofaringeal; nv: cordón nervioso ventral; pg: (parte de) glándula pedal; ph: faringe; sg: glándula de la suela], escala: 30 µm. Figura 15. Eleutheromenia sierra (Pruvot) del área de Trondheim, sección de la región prepaleal (post- pedal) con espículas abdominales (sp) [sd: conducto de la puesta], escala: 50 µm. Figura 16. Macellom - ena adenota spec. nov., sección a la altura de la invaginación prepaleal (post-pedal) del manto (mi) con “glándula abdominal” (ag) justo antes de la abertura y con la abertura de la bolsa de espículas abdomi - nales (sp) [mg: intestino medio], escala: 30 µm.

56 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

14 mg mu

ph gl mg bu dv mu sg pg

nv fo

15 sd

ag mi

57 Iberus , 21 (2), 2003

tances of 50-80 µm causes deep constric - area, the ventral pharyngeal muscles tions of the midgut, forming respective also become concentrated to a pair of lateral pouches. Special musculature is ventral bundles; both extend (in the elaborated in connexion with the poste - present specimen) asymmetrically at the rior foregut. same body side far posteriorly to join Sensory system : Fused cerebral gan - the musculature of the body wall (not glion above the mouth exhibiting a tri - before the middle of the body). angular outline in cross section (ven - In this terminal portion of the trally 125 µm wide, 60 µm high, 50 µm foregut (formation of muscle bundles) long). Laterofrontal pairs of small gan - the buccal ganglia (Ø 25 µm) are elabo - glionic formations innervate the atrial rated laterally (Fig. 14). The ventral sense organ and the mouth opening. glandular organs are separated by the The connectives emerge laterally, the buccal commissure ventral to the very short (20 µm) ventral and lateral foregut; they open ventrolaterally into ones in close contact. The (first) lateral the foregut (Fig. 14). The organs are very ganglion at each side is latero-posteri - small (40-50 µm long, Ø 30 µm), some - orly elongated. The first “ventral” what irregular sacks with glandular swelling, due to the short connective, is epithelium and a narrow outleading located lateroventrally of the cerebral lumen (type C in SALVINI -P LAWEN 1972, ganglion; the true ventral ganglia (Ø 60 1978). µm x 30 µm) are formed above the Midgut possessing a voluminous beginning pedal fold. The remaining rostral caecum extending to body tip nervous system exhibits no unusual (Fig. 9), splitting frontally in the region configuration. The 125 µm long of the mouth to a paired organ. Due to suprarectal commissure is medullary (Ø the serial muscle bundles, there are 20 µm). regular, deep lateral constrictions of the The atrial sense organ is bordered by midgut. The midgut and its caecum the horseshoe-shaped ciliary tract, the include, among dissolved food material, dorsal limbs running parallel in distinct also nettle capsules of Cnidaria. distance. The papillae are single and Gonopericardial system : Paired, blunt (Ø 12-15 µm). A single dorsotermi - hermaphoditic gonad. Eggs at the con - nal sense organ is elaborated middor - necting median walls measure maxi - sally above the posterior rectum. mally Ø 50 µm, indicating that full Alimentary tract : Mouth opening dor - maturity has not been reached. The sally at the rear end of the atrium, single heart auricle is an invagination of behind the curved ciliary tracts. Foregut the pericardial roof, and the ventricle representing an elongate tube, coated represents a largely free organ. There throughout its course by a delicate cir - are two kinds of blood cells: a) small cular and a distinct longitudinal pha - and coarsely structured granulocytes (Ø ryngeal musculature. The epithelium 5 µm); b) finely granulated, round consists in the anterior third of cubical haemocytes (Ø 10 µm). cells (about 6 µm high), further on of The pericardioducts emerge lat - irregularly club-shaped cells (8-12 µm eroterminally. They open from dorsal high). It is intruded (partly in the ante - into the respective spawning duct, the rior third, all along posterior third) and latter bending dorso-posteriorly into a forms up to 12 distinct longitudinal scarcely separated, wide tube: receptac - folds. ulum seminis. The spawning ducts are A short distance in front of the paired in their anterior portion; single ventral opening of the foregut into the opening into the central mantle cavity midgut, the dorsal and lateral longitudi - represents a simple, narrowed and short nal pharyngeal muscles are concen - outlet (pore). There are neither vesiculae trated to a pair of dorsolateral bundles seminales nor accessory genital organs which run transversely to the lateral (copulatory stylets, abdominal spicula). body wall (Figs 9, 14). In that narrow

58 SALVINI -P LAWEN : West-Mediterranean Solenogastres with three new species

Discussion : Among the five genera of U. compostelana it remains an invagina - the family Rhopalomeniidae ( GARCÍA - tion throughout); the different relation ÁLVAREZ AND SALVINI -P LAWEN , 2001), of the foregut muculature (the muscle the present specimen coincides on the layer around the foregut in U. composte - generic level with Urgorria based on the lana is weaker than the bundles at the mantle elaboration, the atrio-buccal terminal foregut, which are also much cavity, the lack of the radula and the stronger than those in the present speci - configuration of the genital apparatus. men 1). The present specimen thus rep - The conformity with the hitherto sole resents a proper species Urgorria mono - species U. compostelana even includes plicata spec.nov. such characters as the special scales at The common atrio-buccal opening in the mantle bridge between the atrio- Urgorria separates this genus from all buccal opening and the pedal pit, the other Rhopalomeniidae, and Urgorria is similar musculature of the foregut, the thus well-defined ( GARCÍA -Á LVAREZ unpaired to paired midgut caecum, and AND SALVINI -P LAWEN , 2 001). At the the receptacula seminis. Only few char - same time, the condition of the ventral acters actually differ from those in U. foregut glandular organs (type C in compostelana : the body cuticle forms no SALVINI -P LAWEN , 1972, 1978) required middorsal reinforcement (in U. com - somewhat altering the definition of the postelana the 40-100 µm thick cuticle family itself (see GARCICA -Á LVAREZ AND with spicules locally forms a middorsal SALVINI -P LAWEN , 2001 versus SALVINI - crest up to 150 µm); only a single pedal PLAWEN , 1978). The type species fold is elaborated, which continues to Rhopalomenia aglaopheniae (Kowalevsky the mantle cavity (in U. compostelana and Marion, 1887) exhibits two pairs of there are two pedal folds which fuse ventral foregut glandular organs (cf. into a single one in the region of the PRUVOT , 1891, N IERSTRASZ AND STORK , anterior spawning ducts and flatten to a 1940, S ALVINI -P LAWEN , 1972, G ARCÍA - mere ridge close to the mantle cavity to ÁLVAREZ ET AL ., 2000a): one pair forming a mere ridge); the position of the dor - subepithelial follicles around short soterminal sense organ differs (above ducts (type A) and one globular pair of the anterior mantle cavity; in U. com - epithelial glands (type C). All other postelana at the rear of the body); the Rhopalomenia species (representing heart ventricle represents a free tube (in Entonomenia Leloup to be restored cf.

SALVINI -P LAWEN 1972) as well as all monoplicata at a fairly shallow depth of other Rhopalomeniidae except Urgorria only 35 meters is worthy of note. (no information for Pruvotia ) possess BIBLIOGRAPHY type A foregut glandular organs only; ARNOVSKY , P., 2000. Spiomenia spiculata , gen. et thus, Urgorria (uniquely type C organs) sp. nov. (Aplacophora: Neomeniomorpha) is well-contrasted also in this respect. collected from the deep waters of the West European Basin. The Veliger , 43: 110-117. Accordingly, we may accept that within BÜCHINGER , Th. AND HANDL , Cl., 1996. Squa- Rhopalomeniidae the ventral foregut matoherpia tricuspidata gen.n. et sp.n. aus der glandular organs became differently Nordsee (Mollusca: Solenogastres: Donder - elaborated at the generic level as siidae). Annalen des Naturhistorischen Muse - “subepithelial (type A) and/or epithelial ums in Wien , 98B: 57-63. (type C) “ organs (see family characters CAUDWELL , C. M., J ONES , A. M. AND KILLEEN , J above). I . ., 1995. Three Solenogastres from the Irish Sea, new to the British marine area. Journal Apart from the presentation of a of Conchiology (London) , 35: 257-269. new species which establishes the occur - rence of Urgorria also in the Western Mediterranean Sea, the finding of U.

59 Iberus , 21 (2), 2003

GARCÍA -Á LVAREZ , O. AND SALVINI -P LAWEN , PRUVOT , G., 1890. Sur queques Néoméniens L. V., 2001. Urgorria compostelana gen.nov. et nouvelles de la Méditerranée. Archives de sp. nov. (Mollusca, Solenogastres, Zoo logie expérimentale et génerale , série 2, 8: Rhopalomeniidae), a new species from off XXI-XXIV. Galicia, Northwest of Spain. Sarsia , 86: 183- PRUVOT , G., 1891. L’organisation de quelques 189. Néoméniens des côtes de France. Archives de GARCÍA -Á LVAREZ , O., S ALVINI -P LAWEN , L. V. Zoologie expérimentale et génerale , série 2, 9: 699- AND URGORRI , V., 2001. Unciherpia hirsuta 810. gen.nov., sp.nov. (Mollusca, Solenogastres: PRUVOT , G. 1897. Essai sur les fonds et la faune Pararrhopaliidae). A new species from Gali - de la Manche occidentale (côtes de Bretagne) cia, Northwest of Spain. Journal of molluscan comparés à ceux du Golfe du Lion. Archives Studies , 67: 113-119. de Zoologie expérimetale et génerale , série 3, 5: GARCÍA -Á LVAREZ , O. AND URGORRI , V., 2001. 511-660. Luitfriedia minuta gen.et sp.nov. (Mollusca: SALVINI -P LAWEN , L. V., 1967a. Neue scandi - Solenogastres), a new species from Galicia, navische Aplacophora (Mollusca, Aculifera). North-West Spain. Cahiers de Biologie marine , Sarsia , 27: 1-63. 42: 197-202. SALVINI -P LAWEN , L. V., 1967b. Kritische Be - GARCIA -Á LVAREZ , O., U RGORRI , V. AND merkungen zum System der Solenogastres CRISTOBO , F. J., 2000a. Rhopalomenia aglaophe - (Mollusca, Aculifera). Zeitschrift für zoologi- niae (Kowelavsky y Marion, 1887) (Mollusca, sche Systematik und Evolutionsforschung , 5: Solenogastres, Rhopalomeniidae), presente 398-444. en la costa norte de la Península Ibérica. SALVINI -P LAWEN , L. V., 1972. Revision der mo - Iberus , 18: 125-131. negassischen Solenogastres (Mollusca, Acu- GARCIA -Á LVAREZ , O., U RGORRI , V. AND lifera). Zeitschrift für zoologische Systematik CRISTOBO , F. J., 2000b. Synopsis of the inter - und Evolutionsforschung , 10: 215-240. stitial Solenogastres (Mollusca). Argonauta , 14: SALVINI -P LAWEN , L. V., 1978. Antarktische und 27-37. subantarktische Solenogastres – Eine Mono - HANDL , C L. AND SALVINI -P LAWEN , L. V., 2001. graphie: 1898-1974. Zoologica (Stuttgart), 44 New records of Solenogastres-Pholidoskepia (128): 1-315. (Mollusca) from Norwegian fjords and shelf SALVINI -P LAWEN , L. V., 1985. New interstitial waters including two new species. Sarsia , 86: Solenogastres (Mollusca). Stygologia , 1: 101- 367-381. 108. HANDL , C L. AND SALVINI -P LAWEN , L. V., 2002. SALVINI -P LAWEN , L. V., 1986. Caudofoveata e New records of Solenogastres-Cavibelonia Solenogastres del Mediterraneo. Bolletino (Mollusca) from Norwegian fjords and shelf Malacologico (Milano), 22: 189-196. waters including three new species. Sarsia , 87: SALVINI -P LAWEN , L. V., 1988. Einige Solenogas - 423-450. tres (Mollusca) der europäischen Meiofauna. HASZPRUNAR , G., 1986. Feinmorphologische Annalen des Naturhistorischen Museums Wien , Untersuchungen an Sinnesstrukturen ur - 90 B: 375-385. sprüglicher Solenogastres (Mollusca). Zoo- SALVINI -P LAWEN , L. V., 1990. The status of the logischer Anzeiger , 217: 345-362. Caudofoveata and the Solenogastres in the HOFFMAN , S., 1949. Über das Integument der Mediterranean Sea. Lavori della Societá Italiana Solenogastren, nebst Bemerkungen über die Malacologica , 23: 5-30. Verwandtschaft zwischen den Solenogas - SALVINI -P LAWEN , L. V., 1997. Fragmented know- tren und Placophoren. Zoologiska Bidrag från ledge of West-European and Iberian Caudo- Uppsala , 27: 293-427. foveata and Solenogastres. Iberus , 15: 35-50. LELOUP , E U., 1948. Un nouveau solénogastre à SALVINI -P LAWEN , L. V., 2003. On the phyloge - peau nue de l’océan glacial arctique, Mi - netic significance of the aplacophoran Mol - cromenia simplex g.nov., sp.nov. Bulletin du lusca. Iberus , 21 (1): 67-97. Musée royal d´Histoire naturelle Belgique , 24 SALVINI -P LAWEN , L. V. AND BENAYAHU , Y., 1991. (19): 1-7. Epimenia arabica spec. nov., a solenogaster MIFSUD , C., 1996. Living Mollusca from cir - (Mollusca) feeding on the alcyonacean Scle - calittoral coastal muds, off western Malta. ronephythya corymbosa (Cnidaria) from shal - La Conchiglia, XXVIII/279, Suppl.: 23-41. low waters of the Red Sea. PSZN I Marine NIERSTRASZ , H., 1909. Die Amphineuren: I.Die Ecology , 12: 139-152. Solenogastren. Ergebnisse und Fortschritte der SCHELTEMA , A. H., 1998a. Class Aplacophora. Zoologie , 1: 239-306. Taxonomic Atlas of the benthic fauna of the NIERSTRASZ , H. AND STORK , H., 1940. Mono - Santa Maria Basin and the Western Santa graphie der Solenogastren des Golfes von Barbara Channel. Mollusca Part 1 (P.V.Scott Neapel. Zoologica (Stuttgart), (99): 1-99. and J.A.Blake, eds), 8 3-47. Santa Barbara Mus. Nat. Hist., California. SCHELTEMA , A. H., 1998b. Class Aplacophora. In Beesley, P. L., Ross, G. J. B. and Wells, A. (Eds.): Mollusca: The Southern Synthesis 60 Fauna of Australia , 5/A: 145-159. CSIRO Publ., Melbourne.