Kathryn A. Coates

A newly documented species of Madracis (Scleractinia: Pocilloporidae) from the Caribbean

ABSTRACT Madracis auretenra, new species, is described for a common, shallow-water, zooxanthellate coral species found throughout the wider Caribbean. This new species is distinguished from other species of the genus by a thin branched, dendritic morphology and depth distribution of 1–60 m. Other characteristics include: non-living basal branch portions; a fairly smooth coenosteum; a distinct line of coenosteal spines centrally located between adjacent corallites; no visible secondary septa in corallites; and closely spaced corallites. Individuals of this taxon have been incorrectly referred to Madracis mirabilis (Duchassaing & Michelotti 1860), which is a deep-water species and which is synonymous with Madracis myriaster (Milne-Edwards & Haime 1849), in several publications subsequent to 1973. Herein, a brief explanation of the taxonomic confusion surrounding M. mirabilis and the undescribed species is provided along with a complete description of this new species of Madracis. Records of the new species are confirmed for Puerto Rico, Curaçao, Grenada, and Bermuda. Authors of many recent studies on “Madracis mirabilis sensu Wells” will need to reconsider and reconfirm the identities of their study organisms.

SHELTER PREFERENCES IN THE ENDEMIC BERMUDIAN HERMIT CRAB, CALCINUS VERRILLI (RATHBUN, 1901) (DECAPODA, ANOMURA)

[Calcinus verrilli, a hermit crab endemic to Bermuda, is unusual in that it inhabits both gastropod tubes (Vermicularia spp. and Dendropoma spp.) and gastropod shells (Cerithium litteratum). It was found in both shelter types, in five marine environments, categorized as intertidal areas, subtidal areas, “boilers”, patch reefs, and rim reefs. We found most males in shells and most females inhabiting tubes. We discovered a size dimorphism, females being larger than males. In the laboratory, when given a choice between shells and tubes, both males and females showed a significant preference for shells. In a Y-maze test of attraction to extracts from tube-forming versus shell-forming gastropods, males showed no discrimination, but females preferred the tube-associated extract. These shelter and size dimorphisms in C. verrilli are best explained by intrasexual competition and differences in the ecology of males and females. Calcinus verrilli, un pagure endemique des Bermudes est particulier par son habitat inhabituel, vivant a la fois dans des tubes (Vermicularia spp. et Dendropoma spp.) et des coquilles de gasteropodes (Cerithium litteratum). Il a ete trouve dans deux types d’abris, dans cinq environnements marins, designes comme zones intertidales, zones subtidales, “boilers”, plaques recifales et bordures recifales. Nous avons trouve la plupart des mâles dans les coquilles et la plupart des femelles dans les tubes. Nous avons decouvert un dimorphisme de taille, les femelles etant plus grandes que les mâles. Au laboratoire, lorsqu’un choix est offert entre coquilles et tubes, les mâles comme les femelles ont montre une preference significative pour les coquilles. Dans un test d’attraction aux extraits soit de tubes, soit de coquillages, les mâles n’ont pas montre de difference, mais les femelles ont prefere les extraits associes aux tubes. Ces dimorphismes en matiere d’abri et de taille sont le mieux expliques par la competition intrasexuelle et les differences dans l’ecologie des mâles et des femelles., Calcinus verrilli, a hermit crab endemic to Bermuda, is unusual in that it inhabits both gastropod tubes (Vermicularia spp. and Dendropoma spp.) and gastropod shells (Cerithium litteratum). It was found in both shelter types, in five marine environments, categorized as intertidal areas, subtidal areas, “boilers”, patch reefs, and rim reefs. We found most males in shells and most females inhabiting tubes. We discovered a size dimorphism, females being larger than males. In the laboratory, when given a choice between shells and tubes, both males and females showed a significant preference for shells. In a Y-maze test of attraction to extracts from tube-forming versus shell-forming gastropods, males showed no discrimination, but females preferred the tube-associated extract. These shelter and size dimorphisms in C. verrilli are best explained by intrasexual competition and differences in the ecology of males and females. Calcinus verrilli, un pagure endemique des Bermudes est particulier par son habitat inhabituel, vivant a la fois dans des tubes (Vermicularia spp. et Dendropoma spp.) et des coquilles de gasteropodes (Cerithium litteratum). Il a ete trouve dans deux types d’abris, dans cinq environnements marins, designes comme zones intertidales, zones subtidales, “boilers”, plaques recifales et bordures recifales. Nous avons trouve la plupart des mâles dans les coquilles et la plupart des femelles dans les tubes. Nous avons decouvert un dimorphisme de taille, les femelles etant plus grandes que les mâles. Au laboratoire, lorsqu’un choix est offert entre coquilles et tubes, les mâles comme les femelles ont montre une preference significative pour les coquilles. Dans un test d’attraction aux extraits soit de tubes, soit de coquillages, les mâles n’ont pas montre de difference, mais les femelles ont prefere les extraits associes aux tubes. Ces dimorphismes en matiere d’abri et de taille sont le mieux expliques par la competition intrasexuelle et les differences dans l’ecologie des mâles et des femelles.]

Problems Determining the Phylogenetic Position of Echiurans and Pogonophorans with Limited Data

The phylogenetic position of Echiura and Pogonophora was recently reconsidered using 346 bp of elongation factor 1‐alpha (EF‐1α). On the basis of these results alone it was suggested that the relationships of Anne lida be reconsidered and that the systematics of the group changed accordingly. An examination of these data, however, reveals difficulties in the original analysis that relate to weighting and the relative inclusion or exclusion of available characters and of taxa. Wholesale revision of the systematics of Annelida or of groups therein awaits the availability of more comprehensive work.

Molecular and morphological variation supports monotypy of the octocoral Briareum Blainville, 1830 (Octocorallia: Alcyonacea) in the Western Atlantic

Abstract The current diagnosis and description of the octocoral genus Briareum ascribes to it a single Caribbean species, Briareum asbestinum. Nonetheless, the combination Briareum polyanthes is commonly used in the scientific literature for the encrusting form of this species, and it has been proposed that growth form, allozyme differences, and secondary chemistry support recognition of the digitate form and the encrusting form as separate species. Through comparison of sclerite sizes and nuclear and mitochondrial DNA sequences, as well as a review of studies of secondary metabolites, we find that variation in these characters is not correlated as much to growth form as to location or habitat. Analyses of traditional morphological characters and molecular data support the monotypy of Briareum in the western Atlantic. The subjective junior synonymy of Ammothea ( = Briareum) polyanthes with B. asbestinum is reiterated and a modified description of the species is provided, including an assessment of intraspecific sclerite variation. Partial mitochondrial gene sequences showed no variation among all forms and locations (Bermuda and The Bahamas), whereas the 18S-ITS1-5.8S-ITS2-28S nuclear ribosomal locus contained multiple unique genotypes within and among individuals, growth forms and geographic locations. Extensive intragenomic heterogeneity in the nuclear ribosomal locus, existing in excess of normal heterozygosity, indicates that the multiple copies of the 18S-ITS1-5.8S-ITS2-28S array are not homogenized through concerted evolution. Since this intragenomic variation requires extensive screening to determine the homology of haplotypes and can confound comparison between individuals, we recommend the future use of single-copy nuclear markers in studies of octocoral systematics and evolution.

New alluroidids (Annelida, Clitellata) from Guyana

A new genus and two new species of Alluroididae are described from Guyana and additional data are provided for two previously known species. Brinkhurstia donaldin. sp. is characterized by very long ribbon-like penial chaetae and an unpaired spermatheca with a sperm-filled diverticulum and opening mid-dorsally at 7/8. Righiella n. gen. is metandric and without penial chaetae; R. jamiesoni n. sp. has a large, unpaired spermatheca (devoid of diverticula) which also opens mid-dorsally at 7/8. Brinkhurstia donaldi and Righiella jamiesoni were found in running waters in creeks, whereas Brinkhurstia americana (Brinkhurst, 1964) and Kathrynella guyanae Omodeo, 1996 were collected in anoxic mud in a pool.

A new species of Grania (Enchytraeidae, Clitellata, Annelida) and redescription of Grania pusilla from a rocky shore in SE Ireland

Two species of marine Enchytraeidae belonging to the genus Grania Southern, 1913, Grania mira sp.nov and Grania pusilla Erseus, 1974, are described from the rocky shores of southeast Ireland. Grania mira has distinctive muscular modifications of the male ducts. Grania pusilla which was previously reported only from the coasts of Norway and Sweden by Erseus (1974), is completely redescribed, including information on many additional morphological characters noted from recent taxonomic literature on Grania. It is reinstated to the level of species. The species has a penial stylet and a large glandular penial bulb. Differences in setal distribution between specimens of G. pusilla from Ireland and those from Norwegian and Swedish populations are attributed to geographical separation limiting genetic exchange. This is the first report of Grania in Ireland since Southerns discovery of Grania maricola in 1913. Grania maricola shares a structurally simple penial bulb type with G. pusilla, but the species differ i...

Scleractinia, Octocorallia and Antipatharia of Bermuda’s Reefs and Deep-Water Coral Communities: A Taxonomic Perspective Including New Records

The biodiversity of Bermuda’s coral reef fauna has been extensively studied by natural historians and taxonomic specialists since the mid- nineteenth century. Short taxonomic histories of the initial records and names of Scleractinia and Octocorallia found in Bermuda culminate in complete and up-to-date lists of the currently accepted species. There are 26 species of shallow-water azooxanthellate and zooxanthellate scleractinians, and 23 species of deep water azooxanthellate scleractinians reported from within the Bermuda EEZ; 25 species of shallow-water octocorallians and 33 of deep-water octocorals; and eight antipatharians. A few submersible explorations of the mesophotic zone and the deeper environs of Bermuda’s exclusive economic zone have revealed new species records for scleractinians, octocorallians and antipatharians. Recent and new records for six scleractinians, 24 octocorallians and 2 antipatharian species, presented in this review, include the first documentation of the scleractinian families Flabellidae, Stenocyathidae, and Turbinoliidae, the octocoral families Nephtheidae, Chyrsogorgiidae, Isididae, Keroeididae and Clavulariidae, and the antipatharian family Schizopathidae in Bermuda. Explanations are provided for confusion regarding records of Isophyllia rigida, Montastraea annularis, and Siderastraea siderea in Bermuda.

Finding enchytraeid oligochaetes (Clitellata) in hot climates: species occurrence on the shores of Bermuda

Sampling of a wide range of intertidal habitats increased the number of marine enchytraeid species for Bermuda from 12 to 31, of which 15 are believed to be new to science. The new species are in the genera Enchytraeus, Achaeta and Marionina, predominantly of the last named genus (12 of 15 species). Probable reasons for the large number of new records are the inclusion of habitats not previously sampled, such as algal cushions on rocks and seawater outfalls from aquaria, as well as the use of a wet funnel extractor. The ecological distribution of the species illustrates their dependence on moisture and a good supply of oxygen and confirms the view that enchytraeids are unable to live in stagnant, wet habitats, in hot climates. Species richness is comparable with that recorded in faunal studies of temperate shores. It is proposed that estimates of enchytraeid species richness in the tropics and subtropics could be much higher if attention were paid to the physiological requirements of these worms when designing sampling programs.