Summer zooplankton dynamics in the limnetic and littoral zones of a humic acid lake

The limnetic and littoral zooplankton were studied during summer 1989 in Triangle Lake, a humic acid (pH 4.9) bog lake in Ohio, USA. The limnetic zooplankton showed low species richness and biomass, and dominance by the rotifers Kellicottia bostoniensis and Polyarthra vulgaris. In the littoral, species richness and biomass were markedly higher, and the crustaceans Alona guttata, Ceriodaphnia quadrangula, Chydorus sphaericus, Simocephalus serrulatus and Tropocyclops prasinus, and the rotifer Ascomorpha ecaudis were the dominants. The extreme rotifer dominance and lack of cladocerans in the limnetic zone were likely the result of Chaoborus predation. A pronounced mid-summer decline in cladoceran biomass in the littoral was likely due to predation by T. prasinus and Utricularia (bladderwort).     

Description of Eucyclops tziscao sp. n., E. angeli sp. n., and a new record of E. festivus Lindberg, 1955 (Cyclopoida,Cyclopidae, Eucyclopinae) in Chiapas,Mexico

Two new species of the freshwater cyclopoid genera Eucyclops are described, Eucyclops tziscao sp. n. and E. angeli sp. n. Both species belong to the serrulatus-group defined by morphological features such as: the presence of distal spinules or hair-like setae (groups N1 and N2) on frontal surface of antennal basis; the fourth leg coxa with a strong inner spine that bears dense setules on inner side, yet proximally naked (large gap) on outer side; and a 12-segmented antennule with smooth hyaline membrane on the three distalmost segments. Eucyclops tziscao sp. n. is morphologically similar to E. bondi and E. conrowae but differs from these species in having a unique combination of characters, including a caudal ramus 4.05±0.25 times as long as wide, lateral seta of Enp3P4 modified as a strong, sclerotized blunt seta, coxal spine of fourth leg with inner spinule-like setules distally, and sixth leg of males bearing a strong and long inner spine 2.3 times longer than median seta. Eucyclops angeli sp. n. can be distinguished by an unique combination of morphological features: the short caudal ramus; the long spine on the sixth antennular segment of A1; the presence of one additional group of spinules (N12’) on the caudal surface of A2; the presence of long setae in females, or short spinules in males on the lateral margin of fourth prosomite; the strong ornamentation of the intercoxal sclerite of P4, specially group I modified as long denticles; the distal modified setae of Exp3P3 and Exp3P4 in females and males; and the short lateral seta of P5. Finally, we report on a new record of E. festivus in México, and add data on morphology of the species.     

Life history, biomass and production of two planktonic cyclopoid copepods in a shallow subtropical reservoir

Two planktonic cyclopoid copepods (Tropocyclops prasinus andMesocyclops longisetus) were raised in the laboratory to obtainlife history information (duration of embryonic and post-embryonicdevelopment, reproductive performance, longevity, and stage-specificlength and weight values). Animals were maintained at 20 and25°C, and fed ad libitum. Development times were temperaturedependent when food was not limiting, with shorter periods ofembryonic and post-embryonic development and decreased longevityat 25°C. Laboratory data on the duration of developmentand biomass, together with population dynamics data obtainedin the field, were used to estimate summer and winter biomassand production of these species in a shallow reservoir, LagoaDourada, Brazil. The maximum production rate of T. prasinus,attained during summer, was 2.8 mg dry weight (DW) m^–3day^–1 and the highest daily production:biomass (P:B) ratiowas 0.29, whereas for M. longisetus the maximum production ratewas 1.4 mg DW m^–3 day^–1 and the highest daily P:Bratio was 0.39, in the winter. Over short time intervals (everyother day), there was great variability of the species productionrates. Species production rates were low compared to valuesreported in the literature for the same or other species ofequivalent sized copepods from both tropical and subtropicalregions.     

A new species of Tigriopus (Copepoda, Harpacticoida, Harpacticidae) from Thailand with the description of its naupliar development

Both genders of Tigriopus thailandensis sp. nov. are described from a laboratory stock raised from individuals collected from the seaweed Enteromorpha clathrata in Thailand (Bangsaen Beach, Chonburi Province). Tigriopus thailandensis sp. nov. shares with its closest relative T. japonicus Mori, 1932 two setae on the third exopodal segment of leg 4 while other congeners bear 3 inner setae. However, allobasis and exopod of antenna in both genders are much more slender and elongate than in T. japonicus. All six naupliar stages of T. thailandensis are described from the offspring of isolated females. In comparison with nauplii of T. japonicus, T. thailandensis nauplii are characterized by the following: a smaller body size throughout the naupliar phase; first antennular segment without seta, second antennular segment with only one small seta plus two longer setae; third antennular segment with additional spinules from naupliar stage II onwards; antenna bears three small spinules on the terminal exopodal segment; one additional seta on the anterior surface of the antennary basis, tubular endopod of antenna with one tiny seta midlength at naupliar stage III that increases in size; mandibular basis with several spinules on anterior surface; mandibular coxa with one spinulose seta that is smooth in T. japonicus.     

Chromis okamurai,a new damselfish from the Okinawa Trough,Japan

A new pomacentrid fish,Chromis okamurai, is described from a single specimen taken from the Okinawa Trough (25°53.4′N, 123°59.4′E), in 135–175 m. This species is most closely related to the deep-dwellingC. mirationis, sharing with it the same meristic data (in particular XIV dorsal spines and 2 upper and lower caudal spinules), large eye, and relatively deep body. It differs in having a small round posterior nostril (large and slit like inmirationis), longer second anal spine, shorter pelvic fins, and in color: two dark brown stripes on body and a pale pectoral-fin axil (mirationis has a single, midlateral, yellow to yellowish brown stripe which extends broadly onto lower part of caudal fin, and a black pectoral axil).     

Description of the new subgenus <Emphasis Type="Italic">Metoporaphodius</Emphasis> subgen. n. of the genus <Emphasis Type="Italic">Aphodius</Emphasis> Helw. (Coleoptera,Scarabaeidae) and of the larva of its type species, <Emphasis Type="Italic">A. plustschewskii</Emphasis> D. Kosh.

The new Irano-Turanian subgenus, Metoporaphodius subgen. n., is erected in Aphodius Helw. for A. plustschewskii D. Kosh. (type species) and A. baghlanicus Frolov. The males of Metoporaphodius subgen. n. are distinguished by the presence of a comb of dense setae on hind tibia and by the parameres with spatulate projections. The 3rd instar larva of A. plustschewskii has 2 rows of large flattened spinules on anal stemite (with 10-12 spinules in a row), and 3 spinules on the lacinial apex.     

Mesocosm experiment on the impact of invertebrate predation on zooplankton of a tropical lake

Invertebrate predation on zooplankton was investigated in mesocosms in the shallow tropical Lake Monte Alegre, São Paulo State, Brazil, in the summer of 1999. Two treatments were applied: one with natural densities of prey and the predators Chaoborus brasiliensis and the water mite Krendowskia sp. (Pr+), and another without predators (Pr-). Three enclosures (volume: 6.6 m³ of water per enclosure) per treatment were installed in the sediment of the deepest area of the lake (5.0 m). At the beginning, Chaoborus larvae were present in Pr- enclosures, because of technical difficulties in preventing their entrance, but they virtually disappeared in the course of the experiment. Water mites were almost absent in Pr- enclosures. Chaoborus predation negatively influenced the Daphnia gessneri population, but not the populations of the copepods Tropocyclops prasinus and Thermocyclops decipiens and the rotifers Keratella spp. Death rates of Daphnia were generally significantly higher in the Pr+ treatment; Daphnia densities increased after the disappearance of Chaoborus in Pr-. Copepod losses to predation in the experiment may be compensated by higher fecundity, shorter egg development time, and lower pressure on egg-bearing females, resulting in a lower susceptibility to Chaoborus predation. The predation impact of water mite on microcrustaceans and rotifers in the experiment was negligible.     

Ostreopsis cf. ovata in the Gulf of Gabès (south-eastern Mediterranean Sea): morphological,molecular and ecological characterization

In the last few decades, the frequency of the toxic benthic dinoflagellate Ostreopsis cf. ovata proliferation has increased in the Mediterranean Sea. These blooms are associated with harmful effects on human health and the environment. The present work provides the first long term study on the spatio-temporal distribution of O. cf. ovata in relation to physical parameters in the Gulf of Gabès coastal waters (south-eastern Mediterranean Sea), as well as its morphological, molecular and physiological features. The strains of O. cf. ovata were identified morphologically by light and epifluorescence microscopy. The morphology and the size range of cultured strains were similar to those described regarding O. cf. ovata isolated from the Mediterranean Sea. The ultrastructural analysis of O. cf. ovata cells using the transmission electron microscopy showed the presence of numerous vesicles (VE) containing spirally coiled fibers (SCFs) connected to the mucus canal (CH). The phylogenetic tree based on the internal transcribed spacer region containing the 5.8S rDNA (ITS-5.8S rDNA) revealed that O. cf. ovata strains were placed into the Mediterranean/Atlantic clade. In addition, O. cf. ovata toxicity was evaluated by the mouse bioassay and a dose level ≥ 4 × 10⁴ cells was found to be lethal to mice. The examination of the O. cf. ovata occurrence in the Gulf of Gabès at a large temporal scale (1997–2012) revealed a clear seasonal pattern with dominance from midsummer (July) to late autumn (November). Furthermore, a positive correlation was found between the abundance of O. cf. ovata and salinity, whereas no correlation was found as regards temperature. The occurrence of O. cf. ovata was only detected at salinity above 35 and the highest concentrations were observed at 45. Laboratory experiments confirmed such a result and showed that isolated O. cf. ovata strains had optimal growth at salinity ranging between 35 and 45, with its peak at 40.     

Die GattungEridoconcha Ulrich & Bassler (Eridostraca) im Mitteldevon von Ost-Thüringen

The presence of the genusEridoconcha Ulrich & Bassler 1923 (Eridostraca) is reported for the first time from the Lower Paleozoic sediments of Germany. The three speciesE. spinosa n. sp.,E. papillosa n. sp., andE. cf.rugosa Ulr. & Bassl. are described from the Lower Middle Devonian of eastern Thuringia.     

Mesocyclops thermocyclopoides species-group: redefinition and content

Within the genus Mesocyclops the thermocyclopoides species-group is defined on the basis of the presence of spiniform armature on the maxillar coxa. Examination of nineteen, mainly Palaeotropical species of Mesocyclops and nine representatives of the closely related genus Thermocyclops revealed, that the coxal part of the maxillar syncoxa of the species recently unified in the thermocyclopoides group is adorned with distinct rows of big spinules on its frontal surface. This character, with only one known exception in South Indian M. cf. papuensis, is absent in other species of Mesocyclops and all the Thermocyclops studied here. These species have no spinules on the maxillar coxa at all or very tiny scattered ones.     

Eleocharis khandwaensis sp. nov. (Cyperaceae) from the Madhya Pradesh,India

A new species, Eleocharis khandwaensis Mujaffar, Chandore & S. R. Yadav is described from the Bamangaon village of Khandwa district in Madhya Pradesh state, India. This species belongs to Eleocharis subgen. Limnochloa (P. Beauv. ex Lestib.) Torr. and it is similar to E. lankana T. Koyama but differs in having stolons, weak bristles spinules of perianth, achenes with annulate apex with a short neck, truncate achene base, dark brown to black coloured achenes and nut surface epidermal cells that are isodiametrically hexagonal to pentagonal. Eleocharis khandwaensis grows in ponds along road sides in the Bamangaon and Tirandaz villages.     

Revision of the genus Poromitra (Melamphaidae): Part 2. New species of the group P. crassiceps

Five new species of the genus Poromitra (family Melamphaidae) belonging to the group of species P. crassiceps are described. An important specific feature of this group is the structure of praeoperculum in which bony crests of the anterior edge are at an acute angle to each other, and the posterior and lower edges are uniformly (without break) spinulated with small spinules. In P. decipiens sp. nova described from the Indian Ocean (from the East Indian Ridge), the insertion of ventral fins is located posteriorly the vertical of the posterior edge of pectoral fin insertion, which makes this species similar to P. crassiceps and P. rugosa. The remaining four species have the insertion of ventral fins anteriorly the vertical (or at its level) of the posterior edge of pectoral fin insertion (as in P. unicornis and P. coronata). P. curilensis sp. nova inhabits the northern part of the Pacific Ocean from the Kuril Islands and the Japanese Islands to the Gulf of Alaska; P. indooceanica sp. nova is described from several individuals from the subtropical part of the Indian Ocean; P. glochidiata sp. nova, from catch in the Great Australian Bight; and P. kukuevi sp. nova, from the individual from the western tropical part of the Atlantic Ocean.     

Thekopsora ostryae (Pucciniastraceae,Pucciniales), a new species from Gansu,northwestern China

Thekopsora ostryae, a new rust fungus on leaves of Ostrya japonica collected from Gansu Province was described. Morphological examination using light and scanning electron microscopy showed that this new species is distinct from other species of Thekopsora in the characteristics of ostiolar peridial cells of uredinia and the spinules on the surface of urediniospores. Analyses of the ITS1-5.8S-ITS2 and 28S rRNA gene partial sequences showed that T. ostryae could be a distinct lineage in the genus Thekopsora.     

A new species of the grenadier genus <Emphasis Type="Italic">Coelorinchus</Emphasis> (Actinopterygii: Gadiformes: Macrouridae) from the Timor Sea,Eastern Indian Ocean

Coelorinchus okamurai sp. nov. is described from five specimens collected in the Timor Sea at a depth of 610–690 m. The new species belongs to the Coelorinchus japonicus group (redefined in this study), and differs from all other congeners in having the following combination of features: snout moderately long, sharply pointed in lateral and dorsal views, length 39–42% of head length; lateral nasal ridge completely supported by nasal bone; light organ short, length less than 1/2 orbit diameter, its anterior margin falling far short of pelvic-fin bases; premaxillary teeth in short, uniformly wide band, with posterior end of the tooth band not reaching lateral corner of mouth; no teeth greatly enlarged; body scales covered with short, reclined, narrowly blade-like spinules in widely divergent rows; buttresses of body scale spinules scarcely developed; occipital scales between parietal ridges armed with divergent rows of long, erect, needle-like spinules; nasal fossa usually naked (a few small scales rarely present anteroventrally); patches of small scales sparsely distributed on ventral surface of head; scales on underside of head armed with 1–3 rows of short, erect, needle-like to knife-like spinules; interdorsal space longer than first dorsal-fin base length; subopercle terminating as a long, slender flap; body dark overall without prominent markings; fins uniformly blackish.     

Review of the fossil pufferfish genus Archaeotetraodon (Teleostei, Tetraodontidae), with description of three new taxa from the Miocene of Italy

Three new species of the extinct pufferfish genus Archaeotetraodon are described from the Middle to Upper Miocene of Italy (A. bannikovi nov. sp., A. dicarloi nov. sp. and A. zafaranai nov. sp.), and compared in detail with the three previously described taxa of the genus [A. jamestyleri (Bannikov), A. winterbottomi Tyler and Bannikov and A. cerrinaferoni Carnevale and Santini], which are known, respectively, from the Miocene of Ukraine, the Oligocene of Russia, and the Miocene of Algeria. The three new species described herein bring the number of known Archaeotetraodon species to six, thereby making it by far the most speciose extinct genus of the order Tetraodontiformes. The monophyly of Archaeotetraodon is supported by two derived conditions: bifid scale spinules (versus single spinules in all other tetraodontids), and the fusion of the haemal spine of the penultimate vertebra to the centrum (versus autogenous in all other tetraodontids). We compare a large suite of morphological features of Archaeotetraodon to those found within the group of more basal tetraodontid genera to which we believe it belongs, but we are unable to determine the closest relationships of Archaeotetraodon within that group. Morphofunctional and paleoenvironmental considerations suggest that the species of the genus Archaeotetraodon were adapted to a pelagic or deep-sea lifestyle and were probably able to tolerate relatively low oxygen concentrations. The entire fossil record of the family Tetraodontidae is discussed.     

Taxomomy, ecology and phylogenetic relationships of Bovista pusilla and B. limosa in North Europe

Bovista limosa, described from Greenland, is a species characterised by a prominent, delimited peristome and a fimbriate stoma. Morphological observations have indicated the presence of a closely related species with different peristomal characters, observations that were further confirmed through a molecular phylogenetic study of the Lycoperdaceae where deviating sequences were tentatively named Bovista cf. limosa. Here, we show that Bovista limosa as presently understood consists of two species with slightly different morphology, different habitat preferences, and different albeit overlapping distribution ranges. The two species also have clearly distinct nuclear ribosomal sequences as evidenced by an analysis of the ITS and LSU regions. We demonstrate that Bovista cf. limosa is identical to Lycoperdon pusillum described by Batsch in 1789. Batsch’s fungus has been variously interpreted and is sometimes treated as a nomen confusum. We resolve this confusion by selecting a lectotype from Batsch’s original illustrations and an epitype from the material we have sequenced. A key to the small Bovista species discussed in the paper is provided.     

Verbesina barrancae (Compositae, Heliantheae), a new species from Jalisco, Mexico

Verbesina barrancae, a new species of Compositae (Heliantheae) from Jalisco, México, is described and illustrated. It is morphologically similar toVerbesina crocata but differs in characteristics of inflorescence, anthers, and achenes as well as in form of pollen, size and number of spinules, size of colpus transversalis, and index of polar area.     

Lepraria atlantica,a new species from the British Isles

Abstract:Lepraria atlantica is described as new from acidic rocks in the British Isles; it contains porphyrilic acid, cf. rangiformic acid or rarely cf. roccellic acid, and atranorin. It differs from L. cacuminum in the diffuse, powdery thallus. It is morphologically similar to L. jackii, but differs in the possession of porphyrilic acid.