OBSERVATIONS ON THE GROWTH, REPRODUCTION AND FEEDING OF THE NUDIBRANCH ARMINA TIGRINA

One specimen of the sand-burrowing nudibranch Armina tigrinaRafinesque was collected from South Carolina in June. The specimendeposited a single egg mass of approximately 6500 white eggswhich developed into lecithotrophic veligers in 8 days at 23°C.Of the veligers which metamorphosed, 9 lived 4–5.5 months(i.e. the life cycle was subannual). Eight individuals reachedsexual maturity in about 80 days. Copulation began at a bodylength of 24 mm and oviposition at 28 mm. During the 1.5 monthegg-laying period, each individual laid 2–4 wavy egg masseswith 2000–7000 eggs per mass. Death followed oviposition.Average growth rate of fed and starved pre-ovipositional nudibranchswas 3.4% and 0.9% per day respectively. Growth rate of ovipositingspecimens was 0.6% or less per day. Based on average feedingrates, each nudibranch consumed approximately 1.6 g damp weightof Renilla reniformis (one small colony) between metamorphosisand egg laying and 6.1 g damp weight (about two average colonies)from egg laying to death. Feeding efficiency is presumably increasedby interlocking and abutting radular teeth. Egg diameters reportedfor Armina tigrina from South Carolina and Florida were 199µm and 82 µm respectively. This difference suggeststhe existence of two species of Armina or ne species with twogeographically separated developmental types. Current address: Marine Science Institute, Northeastern University,Nahant, Massachusetts 01908. U.S.A. (Received 10 April 1980;     

EASTERN MEDITERRANEAN OPISTHOBRANCHIA: DOTIDAE (DENDRONOTOIDEA), ARMINIDAE AND MADRELLIDAE (ARMINOIDEA)

An account is given of Doto, Armina and Madrella species collectedon diving and dredging expeditions to the Ligurian, Tyrrhenian,Adriatic, Ionian and Aegean Seas during the period 1973–1988,supplemented by material collected around Naples (southern Italy)and Banyuls (French Côte Vermeille). In all, 5 speciesof Doto, 3 of Armina and 1 of Madrella were investigated, yielding5 new records for the eastern Mediterranean Sea and one speciesnew to science, Armina tricuspidata from the Tyrrhenian Sea.The common arminid on the American coast from North Carolinato Texas is not A. tigrina as claimed by Abbott(1954) and byEyster (1981), but is a new species, for which we propose thename Armina abbotti. Consideration of world-wide records of Madrella leads to theconclusion that the senior Madrella sanguinea Angas, 1864, embracesM. ferruginosa Alder & Hancock, 1864, M. aurantiace Vayssière,1903 and M. granularis Baba, 1949 (but not the Japanese M. gloriosaBaba, 1949, which is probably distinct). ^*T.E. Thompson died in a car accident 1 January 1990. (Received 2 May 1989; accepted 4 November 1989)     

A COMPARATIVE STUDY OF THE MORPHOLOGY OF THE PULMONATE SNAIL PSEUDOTACHEA LITTURATA (PFEIFFER) AND OTHER SPECIES OF PSEUDOTACHEA, IBERUS AND CEPAEA

A population of Pseudotachea litturata (Pfeiffer, 1851) fromTarifa (Càdiz, Spain) has been studied. The morphologicalresults are compared with those from P. splendida, Iberus gualtierianus,I. alonensis, I. marmoralus, I. guiraoanus and four speciesof the genus Cepaea using, as an exploratory method, the Wagnerparsimony procedure and 18 characters of the shell, genitalsystem and karyotype have been analysed. According to this methodit seems that the taxonomical position of P. litturata in thegenus Pseudotachea is confirmed, and agrees with the phylogeneticalrelationships in this group of species. The genus Cepaea seemsto be well established, although two species groups can be distinguished:C. nemoralis—C. hortensis and C. syluatica—C. vindobonensis.These differ mainly in chromosome number, diverticulum lengthand degree of shell polymorphism. Although the present resultsdo not allow us to clarify the current taxonomical problemswithin the genus Iberus, the species studied seem to belongto a natural group (Received 15 September 1987; accepted 1 January 1988)     

TURRILITIDAE (CRETACEOUS AMMONOIDEA) FROM SOUTH AFRICA, WITH A DISCUSSION OF THE EVOLUTION AND LIMITS OF THE FAMILY

The helically coiled mid-Cretaceous family Turrilitidae Meek,1876 are abundant in late Albian and Cenomanian sediments ofEastern South Africa, including representatives of the generaPseudhelicoceras, Turrilites, Hypoturrilites, Ostlingocerasand Mariella, together with a new genus, Neostlingoceras (typespecies Turrilites carcitanensis Matheron, 1842).a Hypoturriliteshomoeomorph derived from Ostlingoceras. Twenty-two species andsubspecies are described, four of them new: Hypoturrilites crickisp. nov., Mariella (Mariella) acanthotuberculata sp. nov., Mariella(Mariella) oehlerti (Pervinquière) sulcata subsp. nov.and Mariella (Mariella) gallienii evoluta subsp. nov. The systematicpart.of the paper providesa basis for the discussion of thephylogeny, and some of the evolutionary trends shown by thefamily. An annotated synopsis of all genera and species referred tothe family is also included (Received 10 March 1977;     

A MOLECULAR FRAMEWORK FOR THE PHYLOGENY OF CORALLIOPHILA AND RELATED MURICOIDS

Coralliophilid gastropods include a large number of described species,grouped in at least seven to 10 'genera' according to their shellmorphology. They are considered closely related to Muricidaeand ranked as a family on its own or as a subfamily of muricids.Their phylogenetic position and relationships are still notdefined. The little anatomical work so far done on this groupseems to indicate a relatively high level of homogeneity, atleast in the alimentary system. There is a need for an independentphylogenetic framework to understand their position and relationshipwithin the muricoideans, and their internal systematics andphylogeny. We have addressed this problem by means of parsimonyanalysis of 609 aligned positions of the sequences coding forthe 12S rDNA. Four coralliophilid sequences representing thesame number of commonly recognized lineages (Babelomurex, Latiaxis,Coralliophila, Galeropsis = Quoyula) were analysed, along withthree sequences of muricoid genera (Stramonita, Phyllonotus,Nucella) representing as many subfamilies of Muricidae, plusthe sequence of the buccinoidean Fasciolaria as outgroup. Maximum parsimonyand neighbour-joining analysis of the dataset, with increasingweighing of transversions versus transitions, yielded similartopologies. Two major outcomes resulted from the analyses: first,the coralliophilid sequences included herein are always monophyletic,with very high bootstrap support in all analyses. This is inagreement with the few anatomical data gathered so far that suggestcoralliophilids are relatively homogeneous. Secondly, the sister-groupof the coralliophilids among the analysed sequences is representedby Stramonita, with high bootstrap support in all analyses.This is in a good agreement with previous molecular analyses andwith the morphological evidence that Rapaninae are the closest sistergroup of coralliophilids. According to the present results,the rank of the coralliophilids should be the same as Rapaninae,therefore a subfamilial status (Coralliophilinae) seems reasonable. (Received 14 August 2000; accepted 30 October 2000)     

ON THE STATUS OF THE GENERIC NAMES OF THE NUDIBRANCH GENERA CATRIONA, CRATENA, HERVIA, RIZZOLIA AND TRINCHESIA

The genus Catriona Winckworth (1941) is synonymous with TrinchesiaPruvot-Fol (1951) but not with Trinchesia von Jhering (1879). It has priority over Trinchesia Pruvot-Fol. The genus Cratena Bergh (1864) is valid and synonymous withRizzolia Trinchese (1877) but not with Hervia Bergh (1871). The genus Hervia Bergh (1871) is synonymous with Facelina Alderand Hancock (1855), but not all species of Hervia can be includedin the latter genus, and these should, therefore, be distributedamong other genera, some of which are listed. (Received 8 October 1954;     

RECRUITMENT AND GROWTH OF THE BLUE-RAYED LIMPET, HELCION PELLUCIDUM (L.), IN SOUTH EAST IRELAND

This account reports on recruitment, growth and population structureof the macroherbivorous gastropod Helcion pellucidum (L.) onan exposed rocky shore in S.E. Ireland, with particular referenceto the pellucidum form. Recently settled Helcion spat were foundinitially on living crustose lithothamnia in pools and on openrock, on the lower shore, during February-April and subsequentlyrecruited to macro-algal fronds. By May they were found in abundanceon Mastocarpus stellatus and Laminaria spp. Helcion was markedlyseasonal in its occurrence on Mastocarpus, being most abundantduring May-August. A complementary pattern was evident on growingHimanthalia receptacles, with limpets abundant from July onwards.It is suggested that Helcion may migrate from Mastocarpus toHimanthalia as they grow. Data on growth rates are presentedfor Helcion in the various habitats studied. Growth rates werehighest on the Laminaria spp. (Received 21 February 1992; accepted 8 June 1992)     

SOME OBSERVATIONS ON THE DIET AND DISTRIBUTION OF NUDIBRANCHS AT SIGNY ISLAND, ANTARCTICA

Observations were made on the diet and distribution of eightspecies of nudibranchs found in Borge Bay, Signy Island, Antarctica.Specimens from seven sites were examined in situ on four separateoccasions during 1992 and 1993 using SCUBA. A small collectionfor identification was also made Six of the eight species presentwere identified, and the first ecological data for at leastone species (Charcotia granulosa) were recorded. Notaeolidiagigas was feeding principally on hydroids of the genus Tubulariaover the entire depth range surveyed (3–36 m), and wasmost abundant in shallow water, whereas Truomella belli wasonly found at deeper sites, mostly on an octocoral of the genusAscolepis. Charcoaa granulosa and Pseudotritoma gracilidensappeared to be specialist bryozoan feeders and, as has beenfound at other locations, Austrodoris kerguelenesis specialisedon the demosponge Dendnlla antarcnca. Two unidentified aeolidspecies occurred almost entirely on particular hydroids andthe prey of Tritonia antarctica was not apparent. The physicalsize of Antarctic nudibranchs may have important implicationsto the type of prey and feeding strategy used by different species. (Received 11 May 1995; accepted 3 December 1995)     

MORPHOLOGY, ANATOMY AND HISTOLOGY OF FLABELLINA AFFINIS (GMELIN, 1791) (NUDIBRANCHIA, AEOLIDOIDEA, FLABELLINIDAE) AND ITS RELATION TO OTHER MEDITERRANEAN FLABELLINA SPECIES

The Atlantic and Mediterranean flabellinid Flabellina affinis(Gmelin, 1791) (Opisthobranchia, Nudi-branchia, Aeolidoidea)is examined morphologically, anatomically and histologicallywith special emphasis on characters which have been widely neglectedin recent literature (e.g. the histological structure of theoral glands, typhlosole). The study provides detailed data aboutall organ systems which are compared to existing data of otherauthors. The species described as Flabellina affinis by Bergh(1875; 1886) is considered not to be conspecific with the Flabellinaaffinis examined in this and other studies. Furthermore, Flabellinaaffinis is compared to other Mediterranean species, especiallyF. ischitana (Hirano & Thompson, 1990). F. ischitana differsfrom F. affinis mainly by the structure of the genital system.The phylogenetic trees presented for the genus by Gosliner &Kuzirian (1990) and Gosliner & Willan (1991) are discussed. (Received 5 August 1996; accepted 9 June 1997)     

THE FINE STRUCTURE AND FUNCTION OF THE FOOT OF NASSARIUS KRAUSSIANUS, A GASTROPOD MOVING BY CILIARY LOCOMOTION

Light and electron microscope studies of the oval foot of Nassariuskraussianus (Dunker) showed that the columellar muscle is asingle extrinsic muscle and dorsoventral, transverse and longitudinalfibres are the principal intrinsic muscles. The fine structureof the columellar muscle and the intrinsic musculature is describedand shown to be similar to that of other gastropods. The presenceof abundant mitochondria in a snail moving by cilia may be relatedto the rapid and powerful movements of the foot made in escapingpredators. All pedal muscle consists of smooth muscle fibresand collagen was observed to be particularly associated withthe intrinsic fibres. The foot maintains a constant area ofpedal sole during ciliary locomotion by means of antagonismbetween the intrinsic muscle fibres. The possible role of collagenin this process is discussed. (Received 6 March 1989; accepted 15 June 1989)     

PHYLOGENY AND BIOGEOGRAPHY OF THE ATLANTIC AND EASTERN PACIFIC HYPSELODORIS STIMPSON, 1855 (NUDIBRANCHIA, CHROMODORIDIDAE) WITH THE DESCRIPTION OF A NEW SPECIES FROM THE CARIBBEAN SEA

A new species, based on two specimens from Guana Island, BritishVirgin Islands, is described. The new species agrees with thegenus Hypselodoris in having a high body profile, a large vestibulargland and mantle glands. It differs from other members of thegenus in the Atlantic Ocean by having a reddish background bodycolour. In addition, dorsal colour patterns such as a broadcentral white line with lateral extensions and the lack of yellowlines or spots further differentiate this species. The radularformula of 52x41.0.41 and a smaller seminal receptacle are alsodistinctive. The phylogenetic relationships of 34 species andsubspecies of Hypselodoris from the eastern Pacific and Atlanticare examined using morphological characters. With the exceptionof the new species, these are characterized by a dark blue backgroundbody colour. The phylogenetic analysis of the data matrix resultedin eight most-parsimonious trees. The resulting consensus treeshows that eastern Pacific and Atlantic species of Hypselodorisconstitute a monophyletic group that is basally split into twosister clades. One clade contains the eastern Pacific speciesand most of the Caribbean species, whereas the other clade containsthe eastern Atlantic species. The new species is the sisterto the rest of the Caribbean species, which also form a monophyleticgroup. This phylogenetic hypothesis suggests that two consecutivevicariant events have affected the biogeography of Hypselodoris:(1) the closure of communication between the tropical Indo-Pacificregion and the Atlantic and eastern Pacific, completed withthe formation of the East Pacific Barrier; and (2) the riseof the Panama isthmus. (Received 19 December 2003; accepted 12 October 2005)     

Correct diagnosis of early zoeal stages of Athanas nitescens (Leach, 1814) (Decapoda, Caridea, Alpheidae) using laboratory-raised larvae

The morphology of the first two larval stages of Athanas nitescens(Leach, 1814), reared under laboratory conditions, is redescribed.The present data are compared with previous works, since a clarificationof the morphological characters of the first two larval stagesof A. nitescens is needed, in order to avoid misidentificationof these stages in the future.     

COMPARISONS OF THE BIOLOGY OF THE INTERTIDAL SUBANTARCTIC LIMPETS NACELLA CONCINNA AND KERGUELENELLA LATERALIS

Two limpet species occur intertidally on subantarctic SouthGeorgia, the patellid Nacella concinna and the siphonarlid Kerguelenellalateralis. N. concinna is confined to the lower shore closeto LWS; K. lateralis occurs in middle shore pools, so theirdistributions do not overlap. N. concinna has a much narrowerthermal niche (–12.9°C to +15.6°C) than K. lateralis(–17.8°C to +31.8°C). Environmental data are presentedto show that the upper lethal temperature of N. concinna islow enough to prevent the limpet living higher on the shore.Both limpet species are slow-moving, but K. lateralis showsincreasing speed with rising temperature, peaking at 15–20°C.In contrast, N. concinna moves actively down to –1.9°C(when sea water freezes), but there is a steady decrease inspeed of locomotion above +2°C. Locomotion ceases at 14°Cin N. concinna (c.f. 30°C in K. lateralis). Both speciesexhibit very low tenacities, but in N. concinna tenacity decreaseswith increasing shell length. In K. lateralis there is no effectof temperature on tenacity. Both species show a positive allometricrelationship between foot area and shell length. N. concinnafeeds upon microbial films and microepiflora, but K. lateraliseats colonial diatoms and Enteromorpha bulbosa. Observationson shell middens of the kelp gull Larus dominicanus showed thatthe gulls did not eat K. lateralis, though they ate great quantitiesof the less accessible N. concinna. Gulls ate N. concinna assmall as 11 mm shell length (within the size range of K. lateralis).Experiments on gulls demonstrated an unwillingness to eat K.lateralis, probably because the siphonariid extrudes a viscidwhite mucus when the foot is touched. (Received 9 May 1996; accepted 8 July 1996)     

THE BIOLOGY AND ECOLOGY OF A BRACKISH LAGOON BIVALVE, CERASTODERMA GLAUCUM BRUGUIERE, IN AN ENGLISH LAGOON, THE WIDEWATER, SUSSEX

Data are presented on population and individual parameters fora population of Cerastoderma glaucum Bruguière livingin a small, almost closed mixohaline lagoon in southern England.The bivalve occupies two discrete niches, a benthic one anda semi-pelagic one, where juveniles are suspended in the floatingalga Chaetomorpha linum Kutz. During the study year (1972) therewas no growth in the benthic population. This was shown to bean unusual occurrence by comparing growth data obtained by severaldifferent techniques, including the microscopic examinationof shell growth lines. Reproductive condition followed the monocyclicpattern already established for this species in northern localities,with spawning taking place in May. Ash content, water contentand calorific content all varied in correspondence with thelevel of starvation, which proceeded with insignificant mortalityuntil body weight was reduced to about a quarter of that atthe beginning of the year. At this point calorific values aslow as 3.5 kcal/g were measured. Possible causes for the anomalousnegative production are considered. The most likely factor responsiblewould appear to be the high production of the alga Chaetomorphalinum which would effectively compete out the phytoplanktonfood of the Cerastoderma population. ^* Present address: Institut für Physiologische Chemie,Abt. Zellbiochemie, Universität Hamburg. Martinistrasse52, 2000 Hamburg 20, F.R.G. (Received 6 November 1978;     

SPERMOGENESIS AND SPERM STRUCTURE IN THREE SPECIES OF PATELLOIDA AND ONE SPECIES OF NIPPONACMAEA (PATELLOGASTROPODA: ACMAEOIDEA)

The spermatozoa of Patelloida profunda albonotata, P. saccharina,P. pygmaea and Nipponacmaea schrenkii (Lottiidae) are describedby transmission electron microscopy. All have ect-aquasperm,typical of invertebrates using external fertilization. The spermof all four species have a cylindrical nucleus (length: breadth> 4: 1 in P. p. albonotata and P. saccharina; <4: 1 inP. pygmaea and N. schrenkii) which tapers towards the roundedanterior end. All have an acrosome with a posterior acrosomallobe which extends into the centre of the subacrosomal space.In P. p. albonotata and P. saccharina the acrosomal contentsare undifferentiated and the posterior lobe extends to the nucleus,being separated from it by flocculent material. In P. pygmaeathe acrosomal contents are differentiated, the lobe is relativelyshort and the subacrosomal space is filled with material witha fibrous appearance. The acrosome of N. schrenkii is undifferentiatedand the posterior lobe is no more than a bulge. The sperm ofP. p. albonotata and N. sacchrina have a small (0.25 µmlong) cytoplasmic collar which surrounds the axoneme anteriorlywhereas in P. pygmaea and N. schrenkii the cytoplasmic collaris longer (1 µm) and is swollen by an electron-dense vesicle.The composition and function of this vesicle is unknown. Thespermatozoa of Patelloida and Nipponacmaea have structural featureswhich are similar to sperm of the Lottiidae providing some supportfor the placement of these genera in the Lottiidae as proposedby Lindberg & Hedegaard (1996) and Sasaki & Okutani(1993) respectively. The similarities of the sperm of P. pygmaeato N.schrenkii raise some doubts about the tax-onomic statusof the former species. Spermiogenesis in all four species issimilar to that described for other Acmaeoidea and Patelloidea.In P. pygmaea and N. schrenkii, however, in addition to theacrosomal vesicle, the Golgi body produces a number of electron-densevesicles which fuse and eventually form a single vesicle inthe collar of the mid-piece. (Received 24 October 1996; accepted 10 February 1997)     

NOTES ON THE TAXONOMY, SPAWN AND LARVAL DEVELOPMENT OF SOUTH AFRICAN SPECIES OF THE INTERTIDAL LIMPET SIPHONARIA (GASTROPODA: PULMONATA)

The taxonomy of South African Siphonaria is reviewed. We concludethat nine species are valid. These are: S. anneae Tomlin, 1944;S. capensis Quoy & Gaimard, 1833; S. compressa Allanson,1959; S. concinna Sowerby, 1824; S. dayi Allanson, 1959; S.nigerrima Smith, 1903; S. oculus Krauss, 1848; S. serrata (Fischer,1807) and S. tenuicostulata Smith, 1903. Of these, Siphonarianigerrima Smith, 1903, has been incorrectly synonymized withSiphonaria carbo Hanley, 1858, which is not present on SouthAfrican shores. S. aspera Krauss, 1848 is reduced to a juniorsynonym of S. Serrata (Fischer, 1807). Shell characteristicsand mode of larval development are described for these nineSouth African species. All species deposit benthic egg massesand development may be either planktonic with swimming veligerlarvae (S. capensis, S. concinna and S. oculus) or direct, withcrawling larvae emerging from the eggs (S. anneae, S. compressa,S. dayi, S. nigerrima, S. serrata and S. tenuicostulata). (Received 20 November 1992; accepted 24 January 1994)     

POPULATION CHARACTERISTICS AND FOOD RESOURCE UTILIZATION OF CONUS IN THE SEA OF CORTEZ AND WEST MEXICO

The diets and population characteristics of three abundant speciesof Conns, nux, diadema and princeps, from the Sea of Cortezare described. All were found to feed predominantly upon polychaeteworms. In addition, food notes are presented for six less abundantspecies from the same area. Comparison of the diversity of thediets of the three dominant species in the Sea of Cortez withcognate species in the Indo-West Pacific, where significantlymore congeneric species occur in any single habitat, indicatedno significant increases in diversity of prey. This lack ofecological release with respect to food in the presence of fewercompeting congeners was attributed to the presence of significantlyfewer prey species when compared to the Indo-West Pacific. (Received 23 March 1978;     

中国蝠蛾属昆虫的种类和地理分布研究

中国分布的蝠蛾属Hepialus(鳞翅目：蝙蝠蛾科),是一类重要的资源昆虫,其幼虫被中华虫草菌Cordyceps sinensis(Berk.)Sacc.寄生感病后形成的虫菌结合体,是我国特产的名贵药材-冬虫夏草。在我国,已知蝠蛾36种,所有的种类均为古北种;其中33种是青藏高原地区分布种,是中国的特有类群,占已知种的91.7%;中亚地区种2个,占5.6%;欧亚地区分布种1个,占2.7%。我国的蝠蛾属主要分布于青藏高原内的西藏、青海、云南、四川、甘肃等省(区)的高寒草甸之中;零星分布于新疆、黑龙江、 内蒙古等省(区)的草原中;全部种类都营土壤内生活。在我国,95%的蝠蛾种类分布区域十分狭窄,常常是不同山脉就形成不同的种类,甚至是同一山脉不同坡向、不同海拔就会形成完全不同的种类。该属昆虫在中国的分布中心是青藏高原东部的横断山系内,位于北纬27°-33°,东经95°～103°之间的区域中,占已知种的80%。蝠蛾垂直分布明显,分布下限在纬度偏南地区海拔约3000m,而偏北地区则约2500m; 分布上限为海拔5100m; 最适分布海拔在4000-4800m之间;最适分布土壤是高山草甸土。蝠蛾的生态地理分布主要受食物、植被、土壤结构、温湿度等生态因子的影响。