Tracing mangrove carbon in suspended matter and aquatic fauna of the Gautami–Godavari Delta,Bay of Bengal (India)

Stable carbon isotopic composition and C/N ratio were used to trace the input of carbon associated with mangrove litter into the estuary of the Godavari–Gautami delta system and Kakinada bay (Andhra Pradesh, India). Suspended organic matter in the mangrove channels was more depleted in ¹³C (average ¹³C = –24.5) than in Kakinada bay which showed ¹³C values for suspended matter (average ¹³C = –22.7) closer to those expected for marine phytoplankton. Suspended organic matter from mangrove channels was enriched in nitrogen (average C/N atom ratio 12.7) and ¹³C (average ¹³C = –24.5) relative to mangrove leaf litter, which had a C/N ratio of 75 and a ¹³C value of –28. Lowest C/N ratios for suspended matter were observed during southwest monsoon when rainfall was highest. Although in general, mangrove litter fall was also lower during this period, no clear correlation was observed between litter fall and C/N ratio of suspended matter. In general, the composition of suspended matter pointed towards phytoplankton as a major component. Isotopic composition of zooplankton suggested selective feeding on ¹³C-enriched, marine phytoplankton in open Kakinada bay and on ¹³C-depleted organic matter, such as estuarine phytoplankton and mangrove litter, in the mangrove channels. From the ¹³C signature, it appeared that mangrove carbon was present to some extent in zooplankton and macrofauna from the mangrove mudflats and channels, but the signal rapidly decreased in Kakinada bay. Nitrogen isotopic composition of zooplankton and macrofauna indicated a progressive enrichment of ¹⁵N away from the mangrove forest towards the northern part of Kakinada bay, in approach of Kakinada city. This is thought to reflect input of anthropogenic nitrogen enriched in ¹⁵N and subsequent uptake of this enriched nitrogen into the aquatic food chain.     

The “Grey Area” in the Northern Bay of Bengal: A Note on a Functional Cooperative Solution

The judgments in maritime delimitation cases involving Bangladesh and Myanmar (2012) and between Bangladesh and India (2014) have resulted in a “Grey Area” in the northern Bay of Bengal involving intersecting and overlapping rights and responsibilities in terms of the exclusive economic zone (EEZ) and continental shelf regimes. This article seeks to identify a functional solution for this Grey Area.     

Studies from the “UWL Helgoland” on the macrobenthic fauna of rocks and boulders in Lübeck Bay (western Baltic Sea)

During a fortnight's saturation mission with the Underwater Laboratory (UWL) Helgoland in May and June 1975, samples of the macrobenthic fauna of rocks and boulders at 15 m depth in the Lübeck Bay were collected from the same area as in October 1974, using a diver-operated suction sampler. Salinity varied from 11.1 to 15.0 S and water temperature from 7.5° C to 11.5° C. Visibility was usually about 3 to 4 m. On average, 10.449 individuals/m² were recorded in 1975 compared to 30.474 individuals/m² in 1974. Two species, the ascidianDendrodoa grossularia and the polychaetePolydora ciliata account for 90.8% of the total number of individuals sampled. Five species (Dendrodoa grossularia, Nereimyra punctata, Neoamphitrite figulus, Asterias rubens, Facelina drummondi) were significantly less abundant than in 1974, while two species and one group of species (Anaitides maculata, Corophium bonelli, Nemertini indet.) were more abundant in 1975. As in 1974, the angle of inclination of the substrate showed no relationship with species composition. In 1974, four motile benthic invertebrates,Nereimyra punctata, Idothea baltica, Diastylis rathkei, andFacelina drummondi were observed swarming. In 1975, onlyI. baltica was observed swarming and the individuals seemed to be less active than in 1974, perhaps related to the lower water temperatures recorded in May and June 1975 compared to those in October 1974.     

Further observations on the fine structure and development of the infracerebral complex (“infracerebral gland”) of Nereis limnicola (Annelida,Polychaeta)

Cell and Tissue Research - The infracerebral complex consists of: (a) two types of ependymoid infracerebral cells located on the ventral surface of the brain, adjacent to a coelomic sinus and blood...     

The Collothecidae (Rotifera,Collothecacea) of Thailand,with the description of a new species and an?illustrated key to the Southeast Asian fauna

Following previous reports indicating a remarkable high diversity of sessile rotifers in Southeast Asian freshwaters, we report on an extensive study of the diversity of Collothecidae rotifers from fifteen freshwater habitats in Thailand. A total of 13 species, including two additional infraspecific variants, of Collothecidae are recorded, one of which is described as a new species of Collotheca. We further add taxonomic remarks on some of the taxa on record and illustrate the uncinate trophi of several representatives by scanning electron microscopic images. Finally, we provide illustrated identification keys to the Collothecidae recorded to date from Southeast Asia.     

Horizontal distribution pattern of the syllid fauna (Annelida: Polychaeta) in the fringing reef lagoon of Anse Forbans (Seychelles, Mahé) and redescription of the abundant Streptosyllis aequiseta

Variability in the effect of solar ultraviolet radiation (UV-B) on primary productivity of natural phytoplankton assemblages was examined in coastal water off Manazuru Harbor, Sagami Bay, central Japan for two full years during the period from September 1996 to September 1998. Solar UV-B, UV-A, and PAR were determined in air and water. Surface water was exposed to UV-B+UV-A+PAR and UV-A+PAR with Mylar film and primary productivity under those two light regimes was determined with ¹³C method. Size distribution of chlorophyll a concentration was also examined. When the occurrence of >10 m size fraction was lower than 80% in a warm season, the UV-B effect was significant. Whenever red tide species occurred, they did not respond to UV-B radiation. Although winter population was also dominated by >10 m size fraction, a ratio of UV-B to UV-A+PAR was already so low that the UV-B effect was insignificant. The occurrence of >10 m size fraction, which might be enhanced by a supply of nitrate and consequently could be related to high supply of dissolved organic matter, seemed to play a significant role in controlling the effect of UV-B on primary productivity in the coastal water. Reduction rate of primary productivity ranged from <10% from November to April to 41% at maximum from May to October with annual reduction rate of 10% in the present study.     

Further notes on New Zealand Enantiobuninae (Opiliones,Neopilionidae), with the description of?a?new genus and two new species

Mangatangi parvumgen. n. and sp. and Forsteropsalis pureroasp. n. are described from the North Island of New Zealand. Pantopsalis listeri (White 1849) and Pantopsalis cheliferoides (Colenso 1882) are redescribed and no longer regarded as nomina dubia; Pantopsalis luna (Forster 1944) is identified as a junior synonym of Pantopsalis listeri. A key to Pantopsalis species is provided.     

Polychaeta “Sedentaria” of Terra Nova Bay (Ross Sea,Antarctica): Capitellidae to Serpulidae

Capitellidae, Maldanidae, Trichobranchidae, Terebllidae, Sabellidae, Serpulidae and Spirorbidae found in Terra Nova Bay (Ross Sea, Antarctica) have been studied. Thirty-one species have been identified, one of which, Praxillella praetermissa antantica is a new subspecies. About 75% of the species are endemic to Antarctica or sub-Antarctica. The geographic distribution of some species has been extended.     

Resting cysts of Parentocirrus hortualis Voß, 1997 (Ciliophora,Hypotrichia), with preliminary notes on encystation and various types of excystation

Resting cysts of Parentocirrus hortualis were investigated, using live observation, SEM and TEM. Processes during encystation and excystation were observed in vivo under the light microscope. During encystation, the trophic body becomes globular, the ciliature is resorbed in an anterior direction, the macronuclear nodules fuse into an elongated mass, and finally a cyst wall develops. As typical for oxytrichids, the resting cysts of P. hortualis are of the kinetosome-resorbing type and their wall is made of four layers: ectocyst, mesocyst, endocyst, and metacyst. The beginning of excystation is indicated by the formation of an excystation vacuole that helps the regenerating specimen to break the cyst wall. The excysting specimen leaves the resting cyst in a thin membrane that is gradually resorbed in the outer environment. Also two other excystation modes were observed. During the rare mode, the excystation vacuole breaks the thin membrane instead of the cyst wall that ruptures under the pressure of the body of the regenerating specimen. During the reproduction mode, the regenerating specimen divides within the resting cyst, producing two to four tomites. This is the first report of division in resting cysts of oxytrichids, but reproduction in division cysts was already described in keronopsids.     

Carbohydrate adducts with zinc-group-metal ions. Interactions of β-d-fructose with Zn(II), Cd(II), and Hg(II) cations,and the effects of metal-ion coordination on the sugar isomer binding

Interaction of β-d-fructose with hydrated salts of zinc-group-metal has been studied in aqueous solution and solid adducts of the type M(d-fructose)X₂·nH₂O, where M = Zn(II), Cd(II), and Hg(II) ions, X = Cl⁻ or Br⁻, and n = 0–2, have been isolated, and characterized by means of F.t.-i.r. spectroscopy, X-ray powder diffraction, and molar conductivity measurements. The marked spectral similarities observed with the Mg(d-fructose)X₂·4 H₂O (X = Cl⁻ or Br⁻) compounds indicated that the Zn(II) and Cd(II) ions are six-coordinated, binding to two d-fructose molecules through O-2, O-3 of the first d-fructose, and O-4, O-5 of the second, as well as to two H₂O. The Hg(II) ion binds to two sugar moieties in the same fashion as do the Zn(II) and Cd(II) ions, resulting in four-coordination geometry around the mercury ion. The crystalline sugar is in the β-d-fructopyranose form, and the coordination of the of the Ca(II) ion takes place through the β-d-fructopyranose isomer, whereas the binding of the Mg(II), Zn(II), Cd(II), Hg(II), and UO²⁺₂ cations could be via the β-d-fructopyranose and the β-d-fructofuranose structures.     

Flora and fauna of the sublittoral hard substrata in the Oosterschelde (The Netherlands) — interactions with the North Sea and the influence of a storm surge barrier

Since 1979 the flora and fauna of the artificial rocky shores of the Oosterschelde estuary have been investigated by diving biologists.Spatial and temporal patterns of species diversity and biomass were studied and several groups of species (communities) were distinguished. A west-east gradient in species composition was found. Species distribution proved to be mainly determined by current velocities, silt and plankton concentrations in the water, underwater irradiance, and the nature of the substratum. Some indications of migration between the basin and the North Sea are shown. Biomass of the hard substratum fauna was compared with that of the soft bottom fauna; the ratio appeared to be about 1 : 2, which is surprisingly high considering the small area available for hard substratum fauna.The key to the interactions with the North Sea is found in the water movements and the volume of water passing through the mouth of the basin during each tide. The abiotic and subsequent biotic changes in the basin caused by the building of the storm surge barrier are discussed, and used to illustrate the measure of dependence of the Oosterschelde on the North Sea.     

Reevaluation of the ‘well-known’ Paraurostyla weissei complex,with notes on the ontogenesis of a new Paraurostyla species (Ciliophora,Hypotrichia)

Two hypotrichous ciliates, Paraurostyla wuhanensis nov. spec. from Wuhan (China) and a new North American population of the Paraurostyla weissei complex, were studied based on live observations and protargol impregnation. Paraurostyla wuhanensis nov. spec. differs from the congeners by the combined features of having six or seven frontal cirri, 2–4 frontoventral cirri, 5–7 ventral rows, and yellow-greenish cortical granules. Ontogenesis proceeds as in the type species, except that fewer frontoventral cirri are formed in the new species. The morphology of the new population of the Paraurostyla weissei complex corresponds well with other American populations. In the phylogenetic trees based on the 18S rRNA gene, Paraurostyla sequences nest in a large clade together with Apoamphisiella and Notohymena. Monophyly of Paraurostyla is rejected by the results of the approximately unbiased test analyses. Morphological, morphogenetic, and phylogenetic analyses show a close relationship between the North American populations of the Paraurostyla weissei complex and Apoamphisiella, indicating that the taxonomic position of the former needs to be reassigned. A new combination, viz. Apoamphisiella polymicronucleata (Merriman, 1937) comb. nov., a reevaluation of the Paraurostyla weissei complex, and emended diagnoses of Paraurostyla and Apoamphisiella, are provided.     

New species of the Monocotylidae (Monogenea) from the stingray Dasyatis tortonesi Capapé (Euselachii,Dasyatidae) off the Tunisian coast,with comments on host-specificity and the specific identities of Mediterranean stingrays

Heterocotyle capapei n. sp. and Thaumatocotyle tunisiensis n. sp. are described from the gills and the nasal cavity, respectively, of Dasyatis tortonesicollected from the Tunisian coast. H. capapei is distinguished from other species in the genus by the morphology of the penis, which is conical and has a long narrow distal point. T. tunisiensis differs from all known species of Thaumatocotyle by the shape and size of the penis. The host Dasyatis tortonesi has long been confused with D. pastinaca. Our study shows that their monogeneans are oioxenic, suggesting that D. pastinaca and D. tortonesi are distinct species. These results suggest that the monogenean parasite fauna could be used as a diagnostic tool for species identification: these parasites may, therefore, represent good biological indicators. The host-specificity of the Heterocotylinae and Merizocotylinae is discussed.     

Eucharitidae (Hymenoptera,Chalcidoidea), a family new to the fauna of Saudi Arabia,with the description of the previously unknown male of Eucharis (Psilogastrellus) affinis Bou?ek

The family Eucharitidae (Hymenoptera: Chalcidoidea) is recorded for the first time for the fauna of Saudi Arabia based on Hydrorhoa caffra (Westwood) and Eucharis (Psilogastrellus) affinis Bouček. The record of Hydrorhoa caffra suggests that Al-Baha and Asir provinces should be considered as part of the Afrotropical rather than the Palaearctic region. The previously unknown male of Eucharis affinis Bouček is described and figured. Macrophotographs of the species are provided.     

New data on the fauna and systematics of Palaearctic species of the click-beetle subfamily Agrypninae Candèze, 1857 (Coleoptera,Elateridae)

New data on the distribution and taxonomy of some Palaearctic species of click-beetles of the subfamily Agrypninae are given. The external morphology and genitalia of the previously unknown females of Compsolacon korotjaevi Gur. and C. agrestis (Vats et Kash.) comb. n. are described. Several taxa are recorded from the following territories for the first time: the genus Eumoeus Cand. from the Palaearctic Region, the species Compsolacon agrestis comb. n. and C. himalayanus Jag. from Afghanistan, Compsolacon turkestanicus (Schw.) from Kyrgyzstan and Afghanistan, Danosoma conspersum (Gyll.) from Kazakhstan, Lacon quadrinodatus Lew. from Russia, and L. unicolor (Cand.) from Iraq. Several Northern Indian species of Agrypnus Esch. are transferred to Compsolacon Rtt., and their systematic positions are briefly discussed: C. agrestis, C. inlustris (Vats et Kash.), C. jacksoni (Vats et Kash.), C. kuluensis (Vats et Kash.), C. maisus (Vats et Kash.), C. planocorpus (Vats et Kash.), C. rameshi (Vats et Kash.), C. repercussus (Vats et Kash.), C. solanensis (Vats et Kash.), C. souslapisus (Vats et Kash.), C. subargillus (Vats et Kash.), C. subfaenum (Vats et Kash.) and C. sublapideus (Vats et Kash.) (all comb. n.). The following new combinations are also established: Compsolacon aequalis (Cand.) comb. n. and Compsolacon brachychaetus (Kollar) comb. n. (both ex Lacon). The following new synonymies are established: Lacon funebris (Sols.) = Adelocera grisea Schw., syn. n.; = Adelocera incompta Kr., syn. n.; Eumoeus murrayi Cand. = Tetralobus quadrifoveatus Vats et Kash., syn. n.