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)     

Comparative sperm ultrastructure and spermiogenesis in basal heterobranch gastropods (Valvatoidea, Architectonicoidea, Rissoelloidea, Omalogyroidea, Pyramidelloidea) (Mollusca)

Three distinct groups of basal heterobranch gastropods (='Allogastropoda/Heterostropha') can be distinguished on the basis o f sperm and spermiogenic features: (1) Valvatoidea; (2) Architectonicoidea; (3) Rissoelloidea + Omalogyroidea + Pyramidelloidea. Sperm of pentaganglionate heterobranchs (Opisthobranchia sensu stricto + Pulmonata) conform in all respects to the pattern shown by group (3). Heterobranchia are united, and differentiated from other gastropods, by a shared suite of sperm and spermiogenic features (rounded acrosomal vesicle, nucleus usually helical, highly modified mitochondrial derivative, spermatid acrosome associated with a dense nuclear plaque, formation of the mitochondrial derivative through fusion of numerous small mitochondria along the length of the axoneme). Sperm autapomorphies of the Architectonicoidea and the Valvatoidea suggest that these two superfamilies arc distinct but terminal offshoots from ancestral heterobranchs.     

Systematics and evolution of the genus Clathrobaculus Cossmann, 1912 (Gastropoda, Mathildidae)

The morphology and ontogeny of Jurassic gastropods those have been included in the genera Clathrobaculus Cossmann, 1912 and Gordenella Gründel, 1990 are discussed. Based on the ontogenetic research of their shells, several types of ontogeny are established in the species of these genera. The suggestion is made that the genus Gordenella should be considered as a junior synonym of Clathrobaculus within the family Mathildidae. The protoconchs of Clathrobaculus species are studied to reveal their morphological variability and a number of distinguishing characters in which they differ from the protoconchs of other mathildid genera. Four species of Clathrobaculus, of which two are new (C. medidilatatus and C. inconstantiplicatus), are described from the Jurassic deposits of the European part of Russia. The composition of C. fahrenkohli (Rouillier, 1846) and C. krantzi (Rouillier, 1849) is emended, and the protoconchs of these species and of the species C. inconstantiplicatus are described for the first time.     

Morphological and anatomical contributions to the taxonomical identification of two <Emphasis Type="Italic">Ornithogalum</Emphasis> taxa (<Emphasis Type="Italic">O. nutans and O. boucheanum</Emphasis>) from Flora of Turkey

In this study, morphological and anatomical features of Ornithogalum nutans and O. boucheanum, two relative and morphologically similar species growing in European Turkey, were investigated. These species showed some important anatomical differences with regard to leaf anatomy while they have identical features in stem. The stem anatomy of these two species displays the common properties of monocotyledons. The mesophyll is unifacial and contains monotypic chlorenchyma cells in the leaf of O. nutans. It has no lacunae. The mesophyll in O. boucheanum is equifacial and it has lacunae. This anatomical distinction may be useful for the identification of these similar-looking species.     

Interesting succulent features in thePinguicula species from the Mexican evolutionary centre

This paper deals with the carnivorous plants of the genusPinguicula occurring particularly in wet habitats. Nevertheless, some species are able to survive longer dry periods in the course of which they form succulent rosettes. Leaf anatomy has been investigated in 6 Mexican species of this kind. The following features frequent in typical succulents have been found: green sheats of vascular bundles (indicating the C₄-pathway of CO₂ assimilation in photosynthesis) and the chlorenchyma located in the lower (= abaxial) part of the mesophyll, under a layer of translucent water-storage tissue. These features are discussed with regard to phylogenetical relationship within the genusPinguicula.     

Phylogeny of the genus Turris: correlating molecular data with radular anatomy and shell morphology

There are over 10,000 species of venomous marine molluscs, the vast majority of these, which are generally referred to as "turrids", are traditionally assigned to a single family, Turridae (Powell 1966). Here, we provide an initial molecular analysis of the type genus of the family, Turris R?ding, 1798, thought to be among the most well characterized groups in the family. We show that the type genus is not monophyletic. We analyzed specimens conventionally assigned to 9 different Turris species using molecular markers, combined with the shell morphology and radular anatomy whenever feasible. The results suggest that species assigned to the genus Turris, provisionally assigned to two different subgenera are not monophyletic. Five previously described species belong to the subgenus Turris (s.s.) R?ding 1798: Turris babylonia, (Linne, 1758), Turris grandis, (J. E. Gray, 1834), Turris dollyae, (Olivera, 1999), Turris normandavidsoni (Olivera, 1999) and Turris spectabilis (Reeve, 1843). With a change in species designation, Turris assyria (formerly T. babylonia1010) is added to a well-defined clade, which is in turn more closely related to Lophiotoma and Gemmula species than to the other five Turris species. We show that these five species conventionally assigned to Turris do not belong in the same subgenus, and form a clade provisionally designated as AnnulaturrisPowell, 1966: Turris annulata, (Reeve, 1843), Turris undosa, (Lamarck, 1816), Turris cristata, (Vera-Peláez, Vega-Luz, and Lozano-Francisco 2000) Turris cryptorrhaphe (G. B. Sowerby, 1825) and Turris nadaensis (Azuma, 1973). Implications of the molecular phylogenetic results and its correlation with radular morphology are discussed.     

Anatomy and systematics of bathyphytophilid limpets (Mollusca, Archaeogastropoda) from the northeastern Pacific

Bathyphytophilus diegensis sp. n. is described on basis of shell and radula characters. The radula of another species of Bathyphytophilus is illustrated, but the species is not described since the shell is unknown. Both species feed on detached blades of the surfgrass Phyllospadix carried by turbidity currents into continental slope depths in the San Diego Trough. The anatomy of B. diegensis was investigated by means of semithin serial sectioning and graphic reconstruction. ‘The shell is limpet-like; the protoconch resembles that of pseudococculinids and other lepetclloids. The radula is a distinctive, highly modified rhipidoglossate type with close similarities to the lepetellid radula. The anatomy falls well into the lepetelloid bauplan and is in general similar to that of Pseudococculinidae and Pyropcltidae. Apomorphic features are the presence of gill-leaflets at both sides of the pallial roof (shared with certain pseudococculinids), the lack of jaws, and in particular many enigmatic pouches (bacterial chambers?) which open into the postcrior oesophagus. Autapomorphic characters of shell, radula and anatomy confirm the placement of Bathyphytophilus (with Aenigmabonus) in a distinct family, Bathyphytophilidac Moskalev, 1978. As revealed by a cladistic study, the Bathyphytophilidae should be classified within the Lepetelloidea close to the Lepetellidae, Pyropeltidae, and Pseudococculinidae.     

Radiolarian taxa from Southern Ocean sediment traps (Atlantic sector)

Summary This study gives a first inventory of radiolarian taxa collected with sediment traps in different areas of the Southern Ocean (Drake Passage, Powell Basin and Bransfield Strait). It includes 66 taxa or taxa groups of which 46 were already described. Two previously described species groups and 20, yet undescribed, taxa are documented. The name Protocystis bicornis (Haecker) is replaced by P. spinosus as it is a later homonym of P. bicornis (Borgert). The occurrence pattern of the radiolarian taxa indicates distinct differences in the species composition between neritic environments (Bransfield Strait and Powell Basin) and pelagic, open ocean conditions (Drake Passage).     

Anatomy of the nasal cavity and paranasal sinuses in Aegyptopithecus and early Miocene African catarrhines

Neontological comparisons suggest that paranasal sinus anatomy is diagnostic of several catarrhine clades such as Cercopithecoidea, Hominoidea, Homininae, and Ponginae. However, while the loss of sinuses in cercopithecoids is generally recognized as a derived condition, determining the polarity of character-state changes within noncercopithecoid catarrhines requires knowledge of the primitive catarrhine condition. To address this problem, the paranasal sinus anatomy of Aegyptopithecus and several early Miocene catarrhines was investigated. Two partial facial skeletons of Aegyptopithecus were subjected to computed tomography in order to reveal their internal anatomy. These data were compared with facial and palatal specimens of Proconsul, Limnopithecus, Dendropithecus, Rangwapithecus, and Kalepithecus in the National Museums of Kenya in Nairobi, and to wet and dry specimens of living taxa. Results confirm that cercopithecoid paranasal anatomy is derived, and reveal that the sinus anatomy of stem catarrhines included a hominoid-like maxillary sinus as well as an ethmofrontal system like that of hominines. Accordingly, these two features do not constitute evidence for the hominoid, hominid, or hominine status of any fossil species. Conversely, the absence of the ethmofrontal sinus system in Sivapithecus and Pongo is synapomorphic. In addition, features of the nasal cavity of Limnopithecus and Kalepithecus support previous suggestions that these taxa are stem catarrhines rather than hominoids.     

THE COMPARATIVE MORPHOLOGY OF THE CANELLACEAE. II. ANATOMY OF THE YOUNG STEM AND NODE

The anatomy of the young stem and node was investigated in 12 species representing all 6 genera of the Canellaceae. The salient anatomical features of this family are as follows: (1) the primary vascular system is pseudo-siphonostelic; (2) druse-type calcium oxalate crystals and ethereal oil cells are characteristic of the parenchymatous tissues; (3) all members of the family exhibit trilacunar nodes; (4) the periderm is superficial in origin with characteristic U-shaped thickened cells; and (5) the sieve-tube members are of a primitive type with obliquely oriented end walls and many unspecialized sieve areas. On the basis of this anatomical investigation, the conclusion that the Canellaceae has a general ranalean affinity is strengthened.     

Wood anatomy of the subfamily Crotonoideae (Euphorbiaceae s.s.) from India: systematic implications with special reference to the taxonomic delimitation of Givotia and Vernicia

The wood anatomy of 15 representative species belonging to 12 genera of nine tribes of the subfamily Crotonoideae (Euphorbiaceae) are comprehensively described with focus on systematic implications. In addition, ecological and evolutionary aspects are evaluated. An identification key to the species based on wood anatomical features is presented. The wood microstructure of the tribes was found to be considerably heterogeneous reflecting an unnatural classification of the subfamily. However, the results confirm the generic relationship within subtribe Aleuritinae and tribe Ricinodendreae. Vernicia and Givotia may be recognized based on wood anatomical and morphological characters. The tribes Micrandreae and Adenoclineae have considerable similarity in wood anatomy. The wood structure of the monogeneric tribes Trigonostemoneae and Geloneae idicate a close relationship with the tribe Crotoneae.     

Leaf anatomy of Raoulia Hook.f. (Compositae, Gnaphalieae)

Leaf anatomy is compared for all species of Raoulia. The species are tabulated according to their lamina structure. Noteworthy anatomical features are lamina type and grade of differentiation, stomatal position, epidermal and cuticle thickness, shape of mesophyll cells, presence or absence of central clear cells, sclerenchyma caps, abaxial collenchyma and protruding midrib. It is shown that leaf anatomy data provide characters which are taxonomically useful in Raoulia. The main subgenera are supported except that the leaf anatomy of R. haastii is anomalous and that of R. youngii is typical of R. subg. Raoulia rather than R. subg. Psychrophyton. The leaf anatomy of R. petriensis is unique in the genus.     

Leaf anatomy and systematics of Homeriinae (Iridaceae)

Leaf anatomy is described in a range of species of the Old World subtribe Homeriinae, including species from all of the eight genera: Barnardiella, Galaxia, Gynandriris, Hexaglottis, Homeria, Moraea, Rheome and Roggeveldia. Homeriinae have bifacial leaves, otherwise unusual among Iridaceae, and an apomorphy for this group. Leaf anatomy also shows some unusual features, notably an 'extra' row of (inverted) vascular bundles in some specieS. A cladistic analysis using a broad range of data demonstrates that Moraea, the largest genus of the subtribe, is paraphyletic. The smaller genera are consistently clustered within Moraea. Subgenus Moraea is heterogeneous and requires redefinition. Although there are insufficient existing data for satisfactory resolution of the relationships of Homeriinae, information from leaf anatomy provides some useful indicators.     

Leaf anatomy and subgeneric affiliations of C3 and C4 species of Suaeda (Chenopodiaceae) in North America

The halophytic genus Suaeda (Chenopodiaceae) includes species with the C3 and C4 photosynthetic pathways. North American species of this genus were investigated to determine whether C3 and C4 leaf anatomy are consistent within the two sections of Suaeda, Chenopodina and Limbogermen, present on this continent. All species from section Chenopodina were found to possess C3 anatomy, whereas all species from section Limbogermen were found to be C4 species. Characteristics of leaf anatomy and chloroplast ultrastructure are similar to those reported from C3 and C4 species, respectively, from the Eastern Hemisphere. All species from section Limbogermen have the suaedoid type of leaf anatomy, characterized by differentiation of the mesophyll into palisade parenchyma and a chlorenchymatous sheath surrounding central water-storage tissue, as well as leaf carbon isotope ratios (_13C) of above -20. All species from section Chenopodina have austrobassioid leaf anatomy without a chlorenchymatous sheath and _13C values of below -20. According to our literature review, the photosynthetic pathway has now been reported for about half (44) of the Suaeda species worldwide. The C3 and C4 photosynthetic syndromes are with few exceptions distributed along sectional or subsectional lines. These findings throw new light on the infrageneric taxonomy of this genus.     

Cuticular anatomy of Sphenobaiera huangii (Ginkgoales) from the Lower Jurassic of Hubei, China

Sphenobaiera huangii (Sze) Hsü is typical Early Mesozoic fossil foliage of Ginkgoales in China. It has been recorded from the Upper Triassic to the Lower Jurassic. The cuticular anatomy is investigated based on material from the type locality, Lower Jurassic Hsiangchi Formation, Zigui County, Hubei Province. The specimens are similar to S. huangii, but contain new information about leaf morphology and cuticular anatomy. Lower and upper cuticle is investigated using light and electron microscopy (LM, SEM, and TEM). Many features are described for the first time, including general structures of lower and upper cuticle, stomata, papillae, and cuticular ultrastructure. At the ultrastructural level, two layers have been distinguished in both lower and upper cuticle, including a homogeneous outer layer with granules and a heterogeneous inner layer with fibrils. Based on a literature comparison between S. huangii and other relevant species of Sphenobaiera, S. huangii may represent the best-known taxon in the genus Sphenobaiera in both leaf morphology and cuticular structures. This study provides the first detailed ultrastructural data on the leaf cuticle of Sphenobaiera, one of the oldest foliage taxa of Ginkgoales, and offers further evidence for potential discussion on the taxonomic relationships of S. huangii with other ginkgoalean taxa.     

Morphological studies in Pandanaceae

In this study the anatomical features of leaves of 3 9 species of Malayan Pandanus (Pandanaceae) are assessed, chiefly from the taxonomic approach. The results show that systematic foliar anatomy (chiefly epidermal and stomatal characters) is of considerable value at the infrageneric, supraspecific level, and that species-clusters corresponding to sectional taxa can be recognized and denned. An infrageneric classification of the Malayan species based on anatomical data is presented. The composition of several generic sections is revised. Some sections appear very uniform, others are internally diverse, with respect to the anatomical features studied. Twelve sections are upheld in Malaya.     

Some heterostrophic gastropods from Triassic St. Cassian Formation with a discussion on the classification of the Allogastropoda

Fifteen species of Heterostropha are described, 12 of them for the first time. All are newly interpreted with regard to their taxonomic relation to fossil and living gastropods. The Streptacidoidea with long Paleozoic history are represented in the Late Triassic St. Cassian Formation by several genera that can be differentiated into four families. The Ebalidae are represented byEbala, with smooth protoconch, Cassianebalidae byCassianebala andLoxebala with axially ornamented protoconch. The Donaldinidae of St. Cassian are represented by one species ofDonaldina and two ofNeodonaldina that stand in the continuation of Paleozoic species ofDonaldina. Architectonicoidea with shells coiled in a plane and Valvatoidea appear in the St. Cassian fauna without known Paleozoic relation. In the former superfamily the Architectonicidae can be recognized in the genusRinaldoconchus with two species. Cassianaxidae withCassianaxis, Amphitomariidae withAmphitomaria, Stuoraxidae withStuoraxis andAmpezzogyra have a sinistral protoconch and planispirally coiled dextral teleconchs. They all resemble different modern species that have similarly small shells. Modern Hyalogyrinidae have withAlexogyra a new representative from the Triassic. The Valvatoidea are represented with the generaCarboninia andBandellina of the Cornirostridae in the Triassic representatives. The relation of described species in the system of the Heterostropha is discussed.     

A new fossil Cedrus species from the early Miocene of northwestern Turkey and its possible affinities

A new fossil species, Cedrus anatolica n. sp., is described from the early Miocene Hançili Formation of Turkey. All analyses were performed on the thin sections housed at Istanbul University – Cerrahpasa. The new species was interpreted as having the closest affinity with the modern Mediterranean species Cedrus atlantica (Endlicher) Manetti ex Carriere and Cedrus libani Richard. The evolutionary line shows some changes in wood anatomy. From the early Cretaceous to the early Miocene, the pits on the tangential walls of the tracheids gradually decreased, the height of rays increased and the number of epithelial cells in the traumatic resin canals increased slightly. These features are similar in three modern species; other wood anatomical features are also quite stable among the new fossil and modern species.