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)     

MAINWARINGIA NEVILL, 1885, A LITTORINID GENUS FROM ASIATIC MANGROVE FORESTS, AND A CASE OF PROTANDROUS HERMAPHRODITISM

On the basis of reproductive anatomy and radula, the poorlyknown genus Mainwaringia Nevill, 1885, is shown to belong tothe Littorinidae. The genus is represented by two species, M.leithii (E.A. Smith, 1876) from India to Vietnam, and a newspecies, M. rhizophila, from Malaysia to Hong Kong. Both occurin mangrove forests. The reproductive anatomy of M, rhizophilais described in detail, and it is interpreted as a protandroushermaphrodite, a condition unique in the Littorinacea. In theintersexual and female stages both closed pallial oviduct andopen prostate are present in the mantle wall, suggesting thatthese structures are not strictly homologous. The affinitiesof Mainwaringiaare discussed, and it is concluded that it maybe most closely related to Littorina s.s. (Received 30 May 1986;     

SPERMATOZA AND SPERMIOGENESIS OF CORNIROSTRA, VALVATA AND ORBITESTELLA (GASTROPODA: HETEROBRANCHIA) WITG A DISCUSSION OF VALVATOIDEAN SPERM MORPHOLOGY

Transmission electron microscopy reveals that spermatozoa ofthe marine gastropods Cornirostra peleucida (Laseron) (Cornirostridate—genusand family newly proposed by Ponder, 1990a) and Orbitestellasp. (Orbitestellidae) closely resemble those of the freshwaterfamily valvatidae. In particular, spermatozoa of Cornirostra,Orbitestella and Valvata share a unique arrangement of helicalridges or channels within the glycogen piece. The sperm midpieceof Orbitestella and Valvata has a lamellar substructure, whilein Cornirostra thus region exhibits a single, continuous mitochondrialsheath around the axoneme. An acrosome could not be positivelyidentified in either Valvata or Orbitestella but appears tobe present in Cornirostra in the form of a hollow, irregularvesicle. Mature sperm nuclei of the three taxa are long, filiformand almost totally penetrated by the axoneme. Nuclei of Orbitestellapossess one or more helical keels (keels absent in Cornirostraand Valvata). The pattern of spermiogenesis observed suportsthe view expressed by recent authors that the Valvatoidea areclosely related to heterobrach gastropods, and should be formallytransferred to the Heterobranchia. (Received 9 September 1989; accepted 30 December 1989)     

AN ULTRASTRUCTURAL STUDY OF SPERMATOZOA OF HELIX ASPERSA AND HELIX POMATIA (GASTROPODA, PULMONATA)

Spermatozoa of the pulmonates Helix aspersa Müller andH. pomatia Linnaeus are examined in detail using transmissionelectron microscopy (TEM). Important features such as the acrosome,perinuclear sheath, nucleus and terminal region of the midpieceare described for the first time. Also presented are the firstultrastructural observations on spermatozoa from spermatophoresin any pulmonate gastropod (H. aspersa). No morphological differencescould be found between sperm taken from spermatophores and thosewithin the hermaphrodite duct in H. aspersa. Spermatozoa ofH. aspersa and H. pomatia snow all the characteristics of euthyneuranspermatozoa, namely: a helically-keeled nucleus; distinctivearrangement of acrosomal components (apical vesicle, acrosomalpedestal), and extremely elongate midpiece (axoneme and glycogenhelix enclosed by matrix and paracrystalline layers). The spermnucleus of both species is short, and the midpiece also formsthe terminal portion of the spermatozoon (glycogen piece absent).The extraordinary positioning of the acrosome in H. aspersa—reflectedbackwards from the nuclear apex—is not observed in H.pomatia, though a perinuclear sheath (possibly another acrosomalcomponent) is present in sperm of both species. Helix spermatozoaare compared with other euthyneuran sperm and briefly discussedfrom the systematic viewpoint. Present address: Department of Zoology, St. Lucia, 4067, Brisbane,OLD, Australia (Received 23 May 1988; accepted 17 August 1988)     

THE MORPHOLOGY OF TOXOGLOSSAN GASTROPODS LACKING A RADULA, WITH A DESCRIPTION OF NEW SPECIES AND GENUS OF TURRIDAE

The morphology of some deep-sea Turridae lacking radulae wasstudied. The main features of their digestive system are theabsence of a radula sac, venom and salivary glands and the reductionor absence of a proboscis. A new genus Teretiopsis including3 new species and T. thaumastopsis (Dautzenberg and Fischer,1896) is described. On the basis of differences of the digestivesystem when compared with other turrids lacking radulae themonotypical subfamily Taraninae Casey, 1904 new status (typegenus Taranis Jeffreys, 1870) is considered. It is shown thatthe process of radula reduction has occurred independently indifferent phylogenetic lines of Toxoglossa—the subfamiliesDaphnellinae and Taraninae among Turridae and the family Terebridae. (Received 8 August 1988; accepted 20 December 1988)     

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;     

INTERSPECIFIC INTERACTIONS AND SCARCITY OF A TROPICAL LIMPET

The øcmaeid limpet Lottia stipulata occurs in the midintertidal zone of rocky Pacific shores from Colombia to ElSalvador. It is regularly present but rare (<1 m^–2)at wave-exposed to semi-protected sites in Panama. The verticaldistribution of Lottia overlaps that of a pulmonate limpet,Siphonaria gigas, the most abundant molluscan grazer in themid zone (28. m^–2). Manipulations of the density of Siphonariasuggest the pulmonate negatively affects the recruitment, growth,and abundance of Lottia. Observations of populations of limpetsin an area undergoing succession support these results –Lottia recruits quickly and reaches high levels of abundance,but cannot maintain high densities as other benthic consumerslike S. gigas settle and increase in numbers over time. Paradoxically,examination of radulae suggests that if ability to use algalcrusts (the major available food) were of primary importance,Lottia would be the superior competitor. However, competitionneed not be invoked, and results can be explained by a one-wayrelationship between these two limpets. Lottia apparently hasno effect on Siphonaria, but the larger pulmonate probably actsas an agent of disturbance by interfering with foraging by Lottiaand by bulldozing or consuming newly-settled individuals. Predationon Lottia by a predaceous gastropod, Purpura columellaris, andby the American oystercatchcr, Haematopus palliatus, is insignificantat most sites, but may be important where these consumers areabundant. The abundance of Lottia appears to be controlled primarilyby disturbance by Siphonaria and by physical factors, not bypredation or competition. ¹Present address: Department of Zoology, University of Massachusetts,Amherst, Massachusetts 01003 ²Present address: Department of Zoology, University of RhodeIsland, Kingston, Rhode Island 02881 ³Order of authorship determined by coin toss. (Received 31 July 1984;     

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;     

THE SYSTEMATIC POSITION OF LAROCHEA FINLAY, 1927, AND INTRODUCTION OF A NEW GENUS AND TWO NEW SPECIES (GASTROPODA: SCISSURELLIDAE)

Species of the gastropod genus Larochea Finlay, 1927 are shownto be scissurellids without an anal shell slit or foramen. TheNew Zealand species, L. miranda Finlay, 1927 and L. secundaPowell, 1937, brood their young in the right subpallial cavityagainst a modified inner lip that is set well behind the aperturalplane. Larochea scitula n.sp. is based on shells from WanganellaBank, southern Norfolk Ridge. Larocheopsis n. gen. is introducedfor a minute species from off northern New Zealand that lacksa shell brood chamber. Larochea miranda and Larocheopsis amplexan.sp. are either gonochoristic with smaller males or consecutivehermaphrodites, while Larochea secunda and L. scitula are evidentlygonochoristic, having mature males and females of similar size. (Received 23 July 1992; accepted 10 December 1992)     

THE GONADS OF MARGARITIFERA AURICULARIA (SPENGLER, 1793) AND M. MARGARITIFERA (LINNAEUS, 1758) (BIVALVIA: UNIONOIDEA).

A detailed study of the gonads of two endangered species of thegenus Margaritifera living in the Iberian Peninsula, Margaritiferaauricularia (Spengler, 1793) and Margaritifera margaritifera(Linnaeus 1758), based on macroscopic and histological observationsis presented. In both species, gonadal tissue occurs withinthe visceral mass without a specific location. In hermaphrodite specimens,male and female acini are mixed in the visceral mass but canbe clearly distinguished by detailed macroscopic study. The gonadaltopography and cycle of Margaritifera auricularia is described forthe first time, indicating that the species is a female hermaphroditeand that gametogenesis occurs from December to March. Fiftypercent of Margaritifera margaritifera specimens studied werehermaphrodites and 50% females. (Received 6 March 2000; accepted 5 June 2000)     

BIOCHEMICAL COMPOSITION OF HELIX SNAILS: INFLUENCE OF GENETIC AND PHYSIOLOGICAL FACTORS

This paper describes the biochemical composition of differentspecies (Helix lucorum, Helix pomatia) and sub-species of snails(Helix aspersa aspersa, Helix aspersa maxima) reared in thesame conditions with a feed (‘Helixal’) speciallydesigned for edible snails. In addition, the composition ofwild H. pomatia and H. lucorum is presented to allow comparisonbetween snails of different origins. Analyses determined thepercentages of proteins, lipids and minerals. They reveal bothsimilarities and differences in composition according to thespecies and the part analysed (whole body, pedal mass, and visceralmass). H. pomatia contains the highest percentage of mineralmatter and the lowest percentage of lipids. Surprisingly, proteincontents are slightly different between artificially rearedH. aspersa maxima of 3 months old and wild H. pomatia. The resultsmake it possible to evaluate nutritional quality of snails withthe composition of the body of four edible snail species. (Received 16 September 1996; accepted 24 May 1997)     

A DEMOGRAPHIC ANALYSIS OF y-NEOTRICULA APERTA (GASTROPODA: POMATIOPSIDAE) POPULATIONS IN THAILAND AND SOUTHERN LAOS, IN RELATION TO THE TRANSMISSION OF SCHISTOSOMIASIS

The results of field work undertaken along the tropical reachesof the Mekong river in Thailand and Laos are presented. Demographicdata concerning the schistosome-transmitting snail y-Neotriculaaperta are examined and related to the life-cycle of this species.On the basis of these data, and a review of the literature,the only available, empirically substantiated, model for thelife-cycle of y-N. aperta (see Upatham et al., 1980) is shownto be equivocal. In this model snails survive the annual spatein the Mekong river as eggs, which remain dormant below theflood waters, whilst the adults die soon after the waters beginto rise. Here, the above described model of ‘egg survival’is shown to fail to balance the demographic equation for y-N.aperta. An alternative model of delayed oviposition with post-spatesurvival of mature snails is proposed and shown to be a betterfit to the available data. The implications of this alternativemodel for the evolutionary biology and ecology of N. apertaare discussed. The possible effects of the Pak-Mul dam project(Northeast Thailand) on local populations of schistosome-transmittingsnails are assessed and the hydrodynamic conditions conduciveto vector snail proliferation are considered. Attenuation ofthe normal flood-cycle of the Mekong river anc alteration ofthe river bed topography will probably lead to increased numbersof N. aperta at Pak-Mul. These changes, together with the influxof casual labour from endemic areas in Laos, may result in anepidemic of human schistosomiasis in Northeast Thailand. (Received 18 April 1994; accepted 23 June 1994)     

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)     

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;     

ANATOMY OF PSEUDOTRITONIA THIELE, 1912 AND NOTAEOLIDIA ELIOT, 1905 (GASTROPODA: OPISTHOBRANCHIA: NUDIBRANCHIA) FROM SIGNY ISLAND, ANTARCTICA

Several species of nudibranch molluscs are abundant amongstthe rich benthic hard substratum communities found close tothe British Antarctic Survey base at Signy Island, in the Atlanticsector of the Antarctic. Over the austral summer 1992/1993,two of the authors (LWB and DKAB) were able to collect someof the lesser known species of Nudibranchia at depths between3 and 40 metres, using SCUBA. New information on morphologyand anatomy of two of these species, Pseudotritonia gracilidensOdhner, 1944 (Charcotiidae, Arminoidea) and Notaeolidia gigasEliot, 1905(Notaeolidiidae, Aeolidoidea) are presented in thispaper. The validity of the species Notaeolidia gigas is strengthened. (Received 9 February 1994; accepted 18 September 1994)     

A PRELIMINARY CLADISTIC ANALYSIS OF NORTH ATLANTIC OENOPOTA MOERCH, 1852 AND PROPEBELA IREDALE, 1918 (GASTROPODA: CONOIDEA)

The phytogeny of 23 species of the conoidean gastropods Oenopotaand Propebela from the North Atlantic is estimated in a parsimonyanalysis based on 26 morphological characters. Mangeha attenuata(Montagu, 1803) is used as outgroup. The results indicate thatmost Propebela species form a mono-phyletic group within theOenopota/Propebela complex, whereas Oenopota constitutes a paraphyleticassembly. The genus Curtuoma Bartsch, 1941 is probably non-monophyletic. (Received 11 September 1995; accepted 8 December 1995)     

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)     

TAXONOMIC REVIEW OF THE TREE SNAIL AMPHIDROMUS ALBERS, 1850 (PULMONATA: CAMAENIDAE) IN THAILAND AND ADJACENT AREAS: SUBGENUS AMPHIDROMUS

Extensive series of Amphidromus Albers, 1850 were collectedfrom low-altitude areas (30–500 m above sea level)in Thailand, Laos, Malaysia, Singapore and Indonesia between1993 and 2004. Data on shell colour, genital and spermatophoremorphology, and radular structure are presented. Five speciesof Amphidromus (Amphidromus) are reviewed, of which four occurin Thailand. Intraspecific variation between populations ofAmphidromus (Amphidromus) atricallosus (Gould, 1843) is considered;three subspecies are accepted and a new subspecies described.Subspecies of A. (A.) inversus (Müller, 1774) and A. (A.)schomburgki (Pfeiffer, 1861) are reconsidered, and a new subspeciesof the latter is described. A dichotomous key to the speciesand subspecies of Amphidromus (Amphidromus) in Thailand is provided. (Received 7 May 2004; accepted 31 March 2005)     

SPERM AND SPERMIOGENIC ULTRASTRUCTURE IN THE MATHILDIDAE WITH A REVIEW OF SPERM MORPHOLOGY AND ITS SYSTEMATIC IMPORTANCE IN THE ARCHITECTONICOIDEA (GASTROPODA)

The ultrastructure of spermiogenesis and spermatozoa is examinedfor the first time in the heterogastropod family Mathildidae(Mathilda brevicula Bavay and Mathilda sp.). Mathildid spermatozoaexhibit the following features: (1) an ovoid acrosomal vesicleshowing curved dense layers basally and underlain by a thincurved plate; (2) a solid, rod-shaped nucleus showing a shallowbasal invagination (nucleus helically keeled in Mathilda sp.);(3) a midpiece composed of a 9+2 axoneme, 9 thick and periodicallybanded coarse fibres (associated with the axonemal doublets)and a continuous mitochondrial derivative; (5) glyco-gen piececomposed of the axoneme surrounded by dense granules; (6) andend piece (paddle-shaped terminally). Results of the study demonstratethat mathildids share the same key sperm and spermi-ogenic featuresobserved in the Architectonicidae. The monophyly of the Architectonicoidea,established by previous authors on anatomical grounds, is thereforeconfirmed using sperm morphology. Spermatozoa of the two mathildidsinvestigated lack the periodically banded midpiece structuresseen in investigated species of Architectonica (A. pcrspectiva(Linnaeus), A. perdix (Hinds)), Heliacus (H. (Heliacus) variegatus(Gmelin)) and Pseudotorinia (P. laseronorum (Iredale)) therebyresembling most closely the spermatozoaof Philippia lutea (Lamarck)and Psilaxis oxytropis (A. Adams) which also lack suchbandedstructures. Given the widely accepted primitive status of theMathildidae within the Architectonicoidea, the genera Philippiaand Psilaxis may prove to be relatively basal rather than advancedgenera within the Architectonicidae. Thi: view needs to be testedby examination of sperm morphology in other genera of the Architectonicidaeand also the basal mathildid genus Tuba sensu lato (= Gegania+ Tubena). Such information will be vital in any future cladisticstudy of the Architectonicoidea. (Received 16 June 1994; accepted 6 February 1995)