M. G. Harasewych

Phylogenetic relationships of the lower Caenogastropoda (Mollusca, Gastropoda, Architaenioglossa, Campaniloidea, Cerithioidea) as determined by partial 18S rDNA sequences

Phylogenetic analyses of partial sequences spanning approximately 450 nucleotides near the 5’end of the 18s rDNA strongly support the monophyly of Apogastropoda and its constituent clades, Caenogastropoda and Heterobranchia. Representatives of the architaenioglossan groups Cyclophoroidea, Ampullariidae and Viviparidae invariably emerge within Caenogastropoda in all analyses. While the Cyclophoroidea and Ampullariidae are monophyletic, the varying position of Viviparidae in all outcomes contradicts its hypothesized sister group relationship with Ampullariidae, and thus the monophyly of Ampullarioidea. Because of the position of Viviparidae, Architaenioglossa does not emerge as a clade in any of our analyses. Campanile consistently emerges between Cyclophoroidea and Cerithioidea, or in a clade with Cyclophoroidea and Ampullariidae, a position not predicted by previous morphological studies. Maximum parsimony analyses of sequence data show Caenogastropoda to comprise a series of sequentially diverging higher taxa. However, maximum likelihood analyses as well as maximum parsimony analyses using only trans‐versions divide Caenogastropoda into two clades, one containing the architaenioglossan taxa, Campaniloidea and Cerithioidea, the other containing the higher caenogastropod taxa included in Eucaenogastropoda (Haszprunar, 1988) [= Hypsogastropoda (Ponder & Lindberg 1997)l. Denser taxon sampling revealed insertions to be present in the 18s rDNA gene of several caenogastropod taxa. Earlier reports (Harasewych et al. 1997b) of reduced sequence divergence levels in Caenogastropoda are shown to be restricted to Hypsogastropoda. Based on a broader taxonomic sampling, divergence levels within Caenogastropoda are comparable to those found within Heterobranchia.

USE OF ASPARTIC ACID RACEMIZATION AND POST-BOMB 14C TO RECONSTRUCT GROWTH RATE AND LONGEVITY OF THE DEEP-WATER SLIT SHELL ENTEMNOTROCHUS ADANSONIANUS

Abstract Slit shells are living fossils which inhabit the continental slope. Aspartic acid racemization in the nacreous layer of the slit shell Entemnotrochus adansonianus is shown to occur at a remarkably high rate, sufficient to provide annual resolution of the ages of samples taken along the growth spiral of the shells, thus providing information on growth rates and longevity. Calibration of the racemization rate was obtained by 14 C analysis of a post-bomb specimen. The form of the racemization curve was determined by a heating experiment at 60°C; a cubic transformation of the D/L values was found to be linear with respect to time. In three specimens in which a detailed series of samples was analyzed, juvenile growth was found to be very rapid and adult growth 1–2 orders of magnitude slower; adulthood is reached in 2–4 years. Analysis of lip and apical samples of additional shells (total n = 9) shows that individuals reaching adulthood have life spans averaging six years (maximum: 14 yr). The life histories of these deep-water gastropods are thus similar to littoral taxa. Analysis of the prismatic layer shows that this racemizes at a much slower rate than the nacreous layer.

Protein Staining and Detection Methods

Publisher Summary This chapter discusses the protein staining and detection methods. The use of organic stains for the detection of proteins, along with the development of electrophoretic techniques, eliminated many of the complications inherent in the liquid moving boundary methods. The use of moist filter paper as an electrophoretic support medium or carrier for zonal electrophoretic separation stimulated the adaptation of a number of histochemical stains for the detection of uncolored proteins. Many of these had already been adapted for the visualization of proteins separated by chromatography. These stains were employed after proteins were fixed or made immobile, so that they would not be lost in the staining solutions. Heating the filter paper to 110°C after electrophoresis was one of the first methods of fixing proteins. Early general protein stains included Bromophenol blue and Amido black. The chapter discusses current gel-electrophoresis protein detection methods to help the investigator to choose the best method for each application, and to indicate areas that might benefit from further development.

The anatomy of the hadal limpet Macleaniella moskalevi (Gastropoda: Cocculinoidea)

The anatomy of the hadal, cocculinid limpet Macleaniella moskalevi is described. This species has a small, symmetrical, cap-shaped shell with a prominent internal transverse septum. As in other cocculinid genera, broad oral lappets and epipodial tentacles are present. Vestigial eyes are also present, but lack pigment and are modified into the basitentacular gland. The unique aortic vessel and associated hemal gland are present. Mantle cavity morphology is characteristic of cocculinid taxa; the cavity contains a pseudoplicatid gill, hypobranchial gland, and shallow brood pouch. Adults are simultaneous hermaphrodites, possessing a gonad with distinct egg and sperm producing regions; the common gonoduct is glandular. The single receptaculum seminis is connected to the anterior gonoduct via an enclosed duct. An enlarged right cephalic tentacle is inferred to function as a copulatory organ. The digestive gland occupies that part of the visceral mass confined above the septum and opens by way of two ducts into the distal esophagus. The anterior digestive tract is characterized by the presence of extremely well-developed esophageal pouches, a cuticularized sublingual pouch, and an unpaired jaw. A subradular sense organ and salivary glands are lacking. M. moskalevi is remarkably unique among previously described cocculinids in the anatomy of the reproductive tract and of the organs associated with the mantle cavity. In particular, the conformation of the nervous system in this species is unknown among cocculinids described thus far. Additional key words: Mollusca, deep-sea Cocculinids are limpet-like gastropods that are found in deep-sea habitats worldwide and are known primarily from bathyal depths. Macleaniella moskalevi LEAL & HARASEWYCH 1999 and Fedikovella caymanensis (Moskalev 1976) remain the only cocculinid species to date that are known to inhabit the hadal zone. Apart from the genus Teuthirostria, which inhabits chitinous cephalopod beaks, cocculinids are exclusively associated with submerged wooden substrates. Despite this consistent and predictable substrate association, it remains unclear whether cocculinids obtain nourishment directly from their substrate or from microbes, detritus, or other food resources associated with the surfaces on which they are found. Ever since their discovery and first description (Dall 1882), cocculinid species have intrigued their investigators with unique combinations of features. These features have proven problematic for the taxonomy of cocculinid limpets because they conflict with the suites a Author for correspondence. E-mail: eestrong@ gwis2.circ.gwu.edu of characters thought to be diagnostic at higher taxonomic levels. Difficulty in determining the taxonomic placement of cocculinids has been exacerbated by the common practice of placing any deep-sea limpet with a modified archaeogastropod organization in the same taxonomic group. Thus, the phylogenetic affinities of the family have remained ambiguous, a fact reflected in their fluctuating taxonomic status. Based on his anatomical investigations of Cocculina, Thiele (1903), stressed the isolated position of this family, but inferred a close relationship to Neritopsina. Later, Thiele (1908) suggested a close relationship between Bathysciadium and Cocculinidae and erected the superfamily Cocculinoidea to include the families Cocculinidae (Cocculina), Lepetellidae (Bathsciadium, Lepetella), and Addisoniidae (Addisonia). This scheme was expanded with the description of material collected during the latter half of the nineteenth century, but remained largely unchanged for the next 80 years. By the 1980s the Cocculinoidea had grown to include nine families representing a variety of deep-sea limpet-like forms: Addisoniidae (Dall 1882), Bathypeltidae (Moskalev 1971), Bathyphytophilidae (MosThis content downloaded from 207.46.13.129 on Sat, 25 Jun 2016 06:16:26 UTC All use subject to http://about.jstor.org/terms

The Cretaceous and Paleocene pleurotomariid (Gastropoda: Vetigastropoda) fauna of Seymour Island, Antarctica

Abstract Leptomaria antipodensis and Leptomaria hickmanae are described from the Upper Cretaceous [Maastrichtian] Lopez de Bertodano Formation, Seymour Island, and represent the first Mesozoic records of the family Pleurotomariidae from Antarctica. Leptomaria stillwelli, L. seymourensis, Conotomaria sobralensis and C. bayeri, from the Paleocene [Danian], Sobral Formation, Seymour Island, are described as new. Leptomaria larseniana (Wilckens, 1911) new combination, also from the Sobral Formation, is redescribed based on better-preserved material. The limited diversity of the pleurotomariid fauna of Seymour Island is more similar to that of the Late Cretaceous faunas of Australia and New Zealand in terms of the number of genera and species, than to the older, more diverse faunas of South America, southern India, or northwestern Madagascar, supporting the status of the Weddelian Province as a distinct biogeographic unit. The increase in the species richness of this fauna during the Danian may be due to the final fragmentation of Gondwana during this period.

The Columbariinae (Gastropoda: Turbinellidae) of the eastern Indian Ocean

Abstract The occurrence of the subfamily Columbariinae in the eastern Indian Ocean is documented for the first time. Of the 5 species recognized, one, Coluzea distephanotis, new combination, has been previously described from the Torres Strait. Additional material suggests that this type locality is erroneous. Four new species, Coluzea aapta, C. icarus, C. liriope and C. gomphos are described. The eastern Indian Ocean species appear to be more closely related to their congeners from off southern and eastern Africa than to those from off New Zealand, suggesting post-Eocene vicariance of at least some elements of the psychrospheric faunas of the Indian and Pacific Oceans.

Rediscovery of Cancellaria corrosa Reeve, 1856 (Gastropoda: Cancellariidae) in the tropical eastern Pacific

Abstract Cancellaria corrosa Reeve, 1856, a species described from an unknown locality and believed by early authors to inhabit “China Seas,” has been found to be a component of the sublittoral fauna of western Central America. A more detailed description of the shell and radula of this species is provided. As specimens have been misidentified in collections as C. decussata Sowerby I, 1832 or C. gemmulata Sowerby I, 1832, features useful to distinguish these species are provided. Examination of the fossil literature for the region indicates that the lineage giving rise to C. corrosa has been present since at least the middle Miocene.

Rediscovery of the Antarctic species Sipho gaini Lamy, 1910 (Gastropoda: Neogastropoda) with remarks on its taxonomic position

Examination of the holotype of Sipho gaini Lamy, 19 10, attributed by recent authors to the genus Chlanidota (Buccinulidae), revealed that this species belongs to the genus Beluturricula and is a senior synonym of Belaturricula antarctica Dell, 1990. A redescription of the shell, anterior alimentary system, and radular morphology of Beluturricula gaini is provided. The genus Belaturricula is transferred to the family Conidae (sensu Taylor et al. 1993) on the basis of its radula, which is composed of hollow marginal teeth. The presence of a large shell, prominent operculum, acinous salivary glands, radular teeth with narrow bases in B. gaini, as well as the absence of buccal lips and rhyncodeal introvert, all indicate af5nities with the conid subfamily Clathurellinae. Because the radula ofPontiothaumu ergata Hedley (19 16) is nearly indistinguishable from that of Belaturricula guini, we reassign Hedleys species to the genus Belaturricula as Beluturricula ergata (Hedley, 1916).

A critical review of Antarctic Conoidea (Neogastropoda)

ABSTRACT The Antarctic Conoidean fauna is critically reviewed based on published data and specimens in the collections of the USNM, IORAS and MNHN. Forty-two species and subspecies of the superfamily Conoidea are recorded as occurring within the Antarctic Convergence (excluding the fauna of the Kerguelen Islands) and are attributed to 14 genera and seven families. These include the new taxa: Antarctospira n. gen. (type species—Leucosyrinx badenpowelli Dell, 1990); Drilliola antarctica n. sp.; Pleurotomella (Pleutoromella) tippetti n. sp.; Pleurotomella (Anomalotomella) petiti n. sp.; Xanthodaphne pastorinoi n. sp. Aforia watsoni is introduced as a new name for Pleurotoma (Surcula) lepta Watson, 1881, non Pleurotoma lepta Edwards, 1861. A lectotype is designated for Conorbella antarctica (Strebel, 1908). New combinations are also proposed. Antarctospira badenpowelli (Dell, 1990), n. comb. (previously assigned to Leucosyrinx); Antarctospira principalis (Thiele, 1912), n. comb. (previously assigned to Typhlomangelia); Antarctospira mawsoni (Powell, 1958), n. comb. (previously assigned to Leucosyrinx); Typhlodaphne paratenoceras (Powell, 1951), n. comb. (previously assigned to Leucosyrinx); Belalora weirichi (Engl, 2008), n. comb. (previously assigned to Oenopota); Pleurotomella (Anomalotomella) innocentia (Dell, 1990), n. comb. (previously assigned to Typhlodaphne); Pleurotomella (Anomalotomella) nipri (Numanami, 1996), n. comb. (previously assigned to Typhlodaphne); Xanthodaphne raineri (Engl, 2008), n. comb. (previously assigned to Pleurotomella); Aforia hedleyi (Dell, 1990), n. comb. (previously assigned to Pontiothauma). The majority of Antarctic conoidean taxa have hypodermic marginal teeth. Although there is a similar relative abundance of conoideans in Antarctic waters to that seen in other well-studied faunas, the low number of conoideans is indicative of the general impoverishment of the gastropod fauna in the region. Fourteen percent (2 of 14) of conoidean genera that occur within the Antarctic Convergence are endemic to Antarctic waters, as are 82% (34 of 42) of the species. Most taxa have very broad bathymetric ranges, some extending from bathyal to hadal depths. The greatest species diversity was at bathyal depths.

Morphological Development of the Radula of Four Species of the Neogastropod Family Muricidae

ABSTRACT Radular ontogenies of four species of the neogastropod family Muricidae are described through comparisons of early post-metamorphic and adult developmental stages, with specific focus on the rachidian (central) tooth. The degree of rachidian transformation during ontogeny varies from minor shape change to addition or loss of structural features important for assigning taxa to subfamilies. Changes include: flattening of the rachidian base and a switch from a short, beak-like to a long, flattened central cusp in the rapanine Stramonita biserialis; a switch from variable, asymmetric to regular, symmetric expression of inner lateral denticles in the basal muricid Timbellus phyllopterus; curvature of the rachidian base at the margins and separation of the pointed base endpoint from the radular membrane to form a marginal cusp in the muricine Chicoreus dilectus; and moderate straightening of the rachidian base in the ocenebrine Vokesinotus perrugatus. From these observations and previous work, we propose a plesiomorphic developmental sequence for the Muricidae and provide supporting evidence for the developmental origins of novel features of the muricid radula.