Species assemblages of cyclopoid Copepoda from Mantecal,Venezuela

A 14 year monitoring of species composition and abundance of cyclopoid copepods throughout the rainy and dry seasons in a flooded savanna at Mantecal, Apure State, Venezuela, is presented. Two characteristic habitats within these water bodies were selected: the open center of small ponds free of emergent vegetation and the surrounding flooded grassland. In total, 13 species were registered, all of which appeared in the flooded grassland and 11 of which occurred in the open water. Ten species were common for the two habitats during the dry season. The highest abundance was found in flooded grassland during the dry season. Eight species showed abundances greater than 1.0 individual per liter in flooded grassland during both seasons; 3 and 7 species were this abundant in the open water during rainy and dry seasons, respectively. Mesocyclops meridianus and Microcyclops varicans were the most abundant species in both habitats and seasons, while Thermocyclops decipiens was the dominant species during rainy season in open water. Principal component analysis indicates that the important species were positively correlated between them (sharing habitat and season).     

Two new genera of cyclopinid copepods (Crustacea) from anchihaline caves on western Mediterranean and eastern Atlantic islands

Troglocyclopina balearica gen nov. ap. nov. and Muceddina multispinosa gen nov. sp. nov. are described from the flooded coastal karst of the Balearic Islands, and from caves on Sardinia, the Balearics, and Lanzarote (Canaries), respectively. Both taxa seem to prefer anchihaline habitats with water salinities in excess of 18%, although Troglocyclopina has also been found in more reduced salinity cave lakes located some distance from the coast. These new taxa are the first cyclopinids to be reported from caves, all previous citations of cyclopinids from hypogean environments relate only to the marine interstitial. The small clutch-size exhibited by Troglocyclopina balearica (two eggs per sac) and the absence of the exopodal seta on the antenna at Muceddina multispinosa are interpreted as troglomorphic features, in addition to the absence of the nauplius eye and the lack of body pigmentation in both taxa. The derivation of both taxa from shallow-water, hyperbenthic marine ancestors is proposed.     

The cyclopoid copepods of a wet campo marsh in central Brazil

Eight species of cyclopoid copepods were recorded from 1979–1983 in the complex microhabitats of a wet campo (campo úmido) marsh in central Brazil. Ectocyclops herbsti and Paracyclops fimbriatus occurred most often in areas with water covering the soil; Muscocyclops therasiae n. sp. occurred mainly in soils with no surface water; while Metacyclops campestris n. sp. showed no distinct microhabitat preference. Occurrence of the remaining four species was too sporadic to determine microhabitat preference. Paracyclops carectum n. sp., Metacyclops campestris n. sp., Muscocyclops therasiae n. sp., Muscocyclops bidentatus n. sp. and Ponticyclops boscoi n. g. n. sp. are described. A key to the New World species of Metacyclops s. str. is provided.     

On the ecology of marine cyclopoid copepods (Crustacea, Copepoda)

The goal of these studies was to improve our understanding ofhow Oithonidae and Oncaeidae can exist in nearly every partof the ocean. In particular, it was intended to obtain quantitativeinformation on reproduction rates and the longevity of adultfemales, and on feeding and growth rates of Oncaeidae. Whenfeeding at relatively high food levels, early copepodids ofOncaea mediterranea ingested     

Yansacyclops ferrarii,new genus,new species (Copepoda: Cyclopoida) from the Amazon Basin,Brazil

Yansacyclops ferrarii, new genus, new species (Copepoda: Cyclopoida) is described from the plankton of Rios Guamá and Acará Grande near Belém, State of Pará, Brazil.     

A new interpretation of the female genitalia in Macrocyclops albidus (Copepoda, Cyclopidae)

The female genital structures of Macrocyclops albidus (Cyclopidae, Eucyclopinae) were studied using light and electron microscopy. The results confirm that the exterior genital area shows only a copulatory pore, located anteromedially on the ventral face of the genital double-somite, and paired gonopores (not directly visible), situated laterally under the P6 plates. An internal seminal receptacle, composed of several parts, is connected to the gonopores by ventro-lateral cuticular extensions or seminal ducts. The lateral site of communication shows a complex set of connections between the seminal receptacle and the oviducts (via the egg-laying ducts). The structure until now designated as ‘transverse ducts’, visible by transparency on the ventral face, is in fact constituted of internal cuticular thickenings resulting of the fusion of the 6th thoracic somite and the 1st abdominal somite forming the genital double-somite and appearing externally as a part of the suture line; the term ‘suture cord’ is proposed to designate it. The functioning of the system is explained.     

Achiasmatic meiosis and complex heterozygosity in female cyclopoid copepods (Copepoda,Crustacea)

In Mesocyclops edax S.A. Forbes, 2n=14, a North American copepod, the females are heterozygous for several interchanges leading to the formation of large rings of chromosomes (rings of 14, or of 12 plus 1 bivalent) at meiotic metaphase, comparable to those of the plant Oenothera, although no chiasmata are present. The chromosomes are more or less metacentric and have large terminal H-segments. In the rings homologous arms are held together by connecting fibers which insert close to the euchromatin-heterochromatin junctions. Coordinated orientation of the zigzag type seems to be the role.     

A new species of Enterognathus (Copepoda, Cyclopoida, Enterognathidae) collected from the Seto Inland Sea, western Japan

A new species of the endoparasitic copepod Enterognathus (Cyclopoida, Enterognathidae) is described from a crinoid host in the Seto Inland Sea, western Japan. This is a third species of the genus and its first occurrence in the Pacific Ocean. The new species is distinguished from two previously known congeners by the morphology of the body somites, caudal rami, antennae and legs. Crinoid parasites belonging to Enterognathus and the closely related genus Parenterognathus have a broad distribution from the northeastern Atlantic through the Red Sea to the West Pacific.     

The cyclopid (Crustacea,Copepoda) fauna of the inland waters of Israel

Four species of the genusMesocyclops (Cyclopoida: Cyclopidae) are reported from Israel:Mesocyclops kieferi Van de Velde, 1984,Mesocyclops aequatorialis similis Van de Velde, 1984,Mesocyclops ogunnus Onabamiro, 1957 andMesocyclops arcanus n.sp. The new species, close toM. kieferi, is described and some remarks are given for the other species.     

A new species of Ochridacyclops (Kiefer, 1937) (Copepoda, Cyclopoida) from Japan

A new species of cyclopoid copepod, Ochridacyclops nipponensis is described from Japan. This is the third species of the genus. The type material was collected from small streams in the mountainous regions in Shikoku. The new species can easily be distinguished from other members of genus by its 12-segmented antennule, by the proportional length of genital double-somite relative to the length of 3 free abdominal somites, and by the shape of caudal rami. The male is unknown.     

Arenopontia (Neoleptastacus) huysi, sp. nov. (Crustacea, Copepoda, Harpacticoida) from marine interstitial of Montenegro (S.E. Europe)

A new species of Arenopontia (Neoleptastacus) is described on the basis of a single female collected from one sandy beach in Montenegro, Adriatic Sea. With the addition of the new species, the subgenus Neoleptastacus now includes 18 species throughout the world. At the end of this paper there is a key for their determination. Received: 20 March 1999 / Received in revised form: 15 September 1999 / Accepted: 21 September 1999     

Three new genera and five new species of misophrioid copepods (Crustacea) from anchialine caves on Indo-West Pacific and North Atlantic Islands

Hydra lirosoma sp. nov. is a small, hermaphroditic species possessing broad holotrichous isorhiza nematocysts. The spherical embryo and cobbled embryotheca set it apart from similar species. Hydras with broad holotrichous isorhizas form a distinct cluster of species, but one which was not explicitly represented in the three genera ( Pelmatohydra, Hydra and Chlorohydra ) recognized by Schulze (1917, Archiv für Biontologie, 4(2 ): 29). Schulze failed to recognize this group because of the small number of species known at that time. The hydras that are known now fit naturally into four clusters of species termed, in this paper, the oligactis, vulgaris, viridissima, and braueri groups.     

Copepods from ground waters of Western Australia, VII. Nitokra humphreysi sp. nov. (Crustacea: Copepoda: Harpacticoida)

Nitokra humphreysi sp. nov. (Harpacticoida: Ameiridae) is described from anchialine ground waters of the Cape Range karst area in northwestern Australia. The new species belongs to those species of the genus Nitokra Boeck, 1865 with a reduced number of spines/setae on the basoendopodite of the female fifth leg. It is remarkably similar to N. reunionensis Bozic, 1969 and to N. laingensis Fiers, 1986, but there are clear distinguishing features. Nitokra humphreysi sp. nov. has clear stygomorphic features, being colourless and lacking the nauplius eye.     

Intertidal interstitial Halicyclops from the Brazilian coast (Copepoda: Cyclopoida)

H. tageae sp. n. and Halicyclops ytororoma sp. n. are described from the intertidal interstitial water of Brazilian beaches. H. tageae is distinguished from all congeneric species by the number of setae on legs 1–4 endopodite 2 (1, 1, 2, 2) and by possessing a reduced inner spine on the leg 5 exopodite. It shares with H. brevispinosus, H. pusillus and H. canui the spine formula 2, 3, 3, 3 on exopodite 3 of swimming legs 1–4. H. ytororoma closely resembles H. gauldi and differs from this species by having 4 setae on leg 1 endopodite 3; H. gauldi has 3 setae on this segment.This is the first record of Halicyclops from marine interstitial water in Brazil.     

Maricoccus atlantica gen. nov. sp. nov., isolated from deep sea sediment of the Atlantic Ocean

A taxonomic study was carried out on strain 22II-S10r2^T, which was isolated from the deep sea sediment of the Atlantic Ocean using oil-degrading enrichment. The bacterium was Gram-negative, oxidase positive and catalase negative, spherical in shape, and motile by polar flagella. Growth was observed at salinities of 0.5–7 % and at temperatures of 10–41 °C. The isolate was capable of aesculin hydrolysis, but unable to reduce nitrate to nitrite or degrade Tween 80 or gelatine. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 22II-S10r2^T belonged to the family Ectothiorhodospiraceae, with highest sequence similarity to Thioalkalivibrio sulfidiphilus HL-EbGR7^T (90.9 % similarity). The principal fatty acids were Sum In Feature 8 (C_18:1 ω7c/ω6c (29.9 %), C_18:1 ω9c (13.5 %), C_16:1 ω5c (12.3 %), C_12:03OH (6.8 %), C_18:1 ω5c (5.7 %) and C_16:0 (5.3 %). The G+C content of the chromosomal DNA was 60.7 mol%. The respiratory quinone was determined to be Q-7 (25 %) and Q-8 (75 %). Phosphatidylethanolamine, phosphatidylglycerol, aminophospholipid, glycolipid, three phospholipids and lipid were present. The strain was aerobic, non-phototrophic and non-chemolithoautotrophic. The combined genotypic and phenotypic data show that strain 22II-S10r2^T represents a novel species within a novel genus, for which the name Maricoccus atlantica gen. nov. sp. nov. is proposed, with the type strain 22II-S10r2^T (=CGMCC NO.1.12317^T = LMG 27155^T = MCCC 1A09384^T).     

Thioclava atlantica sp. nov., isolated from deep sea sediment of the Atlantic Ocean

A taxonomic study was carried out on strain 13D2W-2^T, which was isolated from a sulphur-oxidizing bacterial consortium, enriched by the deep-sea sediment of the Atlantic Ocean. The isolate was observed to be Gram-negative, oxidase- and catalase-positive, short rod-shaped and motile by means of a flagellum. Growth was observed at salinities from 0.5 to 12 % and at temperatures from 4 to 41 °C, and the strain found to be able to reduce nitrate but not degrade gelatin. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 13D2W-2^T belongs to the genus Thioclava, with highest sequence similarity of 97.8 % to Thioclava dalianensis DLFJ1-1^T, followed by Thioclava pacifica TL 2^T (97.7 %), while the sequence similarities to other members of the genus were all below 97.0 %. The digital DNA:DNA hybridization estimated values between strain 13D2W-2^T and, respectively, T. dalianensis DLFJ1-1^T and T. pacifica TL 2^T were 22.6 ± 2.4 and 25.6 ± 2.4 %. The ANI values between strain 13D2W-2^T and T. dalianensis DLFJ1-1^T and T. pacifica TL 2^T were 78.49 and 81.91 % respectively. The principal fatty acid identified was Summed Feature 8 (C_18:1 ω7c/ω6c) (74.38 %). The isoprenoid quinone of strain 13D2W-2^T was identified as Q10 (100 %). The major polar lipids of strain 13D2W-2^T were found to be comprised of phosphatidylethanolamine, phosphatidylglycerol, an aminophospholipid, a glycolipid and three unknown phospholipids. The G+C content of the chromosomal DNA was determined to be 65.3 mol%. The combined genotypic and phenotypic data show that strain 13D2W-2^T represents a novel species of the genus Thioclava, for which the name Thioclava atlantica sp. nov. is proposed, with the type strain 13D2W-2^T ( = MCCC 1A02612^T = LMG 27145^T).