News from a small island – first record of a freshwater shrimp (Decapoda,Atyidae, Caridina) from Peleng,Banggai Islands,Indonesia

The Indonesian island Sulawesi is well known for its fascinating fauna. Among the atyid and palaemonid freshwater shrimps described from Sulawesi are also a number of endemic species. In contrast, freshwater shrimps have never been reported from the nearby and smaller Peleng Island. Here we describe Caridina thomasi sp. nov. as a first record of an atyid freshwater shrimp from Peleng and compare it with atyids from Sulawesi and other localities. The new species is probably endemic to the island and shows some characters never described in the genus Caridina before. However, a molecular phylogeny of atyid shrimps from the Indo‐West Pacific based on mitochondrial DNA (16S) places C. thomasi within a clade of typical species of Caridina. We tentatively assign the new species to the genus Caridina and discuss the possibility of future changes in the classification of species in this genus.     

III.—Idatiella China: Two new species,with a key (Hemiptera,Miridæ)

Summary

Nine soil, freshwater, and marine species of Thecamoeba have been isolated and investigated, and nine other probably or possibly valid species were reviewed from the literature. Locomotive form/behaviour and interphase nuclear structure are adequate to distinguish all known species, and on that basis the diagnoses of several species have been clarified and questions of possible synonymy resolved.

Most known species can be placed into either a rugose or a smooth group, but it is not yet clear that the genus can be formally divided along that line.

Feeding experiments and observations on six soil and freshwater species showed interspecific differences in the kind of protozoan prey ingested. Species also differed in their rate of multiplication in culture.

One recently discovered species, T. proteoides, approaches Amoeba proteus in both morphological and cultural characteristics more than does any other known species of Thecamoeba but is clearly a member of the latter genus.     

Freshwater sponges of the West Indies: Discovery of Spongillidae (Haplosclerida,Spongillina) from Cuba with biogeographic notes and a checklist for the Caribbean area

The paper reports the first finding of freshwater sponges from the Greater Antilles. Spongillidae belonging to four species of the genera Ephydatia, Anheteromeyenia, and Radiospongilla were found in a variety of freshwater habitats in western Cuba. Anheteromeyenia cheguevarai nov. sp. is described. Morphological traits of sponges from West Cuba were characterized by light microscopy and scanning electron microscopy and compared to the spongillofauna of the Nearctic and Neotropical regions and the pan‐Caribbean area. The specific richness and the discovery of a new species suggest a high diversity of the Antillean freshwater sponges although the investigated area of Cuba is relatively small.     

Zoogeography and evolutionary ecology of the genus Platorchestia (Crustacea,Amphipoda, Talitridae)

ABSTRACT

Species of the genus Platorchestia occur both in the northern hemisphere (18 species) and southern hemisphere (three species plus a synanthropically introduced species in South America and South Africa). The greater number of endemic Platorchestia species in the North Pacific Ocean suggests that it could be the epicentre of evolution for this genus. North-western Pacific Platorchestia includes 15 species which occupy five ecotopes: wrack (seven species), terrestrial leaf litter (five species), freshwater (one species), marsh (one species) and tentatively present in caves (one species). North-eastern Pacific Platorchestia includes only one putative driftwood specialist, with no other species found in North American coastal habitats. This compares with three good endemic Platorchestia species (plus two putative additional species) and only two ecotopes: wrack (three species) and freshwater (two species) from the North Atlantic Ocean, inclusive of the Gulf of Mexico and Mediterranean Sea. Insufficient data is available to consider Platorchestia zoogeography for the Arabian Sea and Bay of Bengal. Synanthropic dispersal involving Platorchestia in Polynesian outrigger canoes, or in solid ballast carried in the holds of wooden sailing ships has been identified as a potential complicating factor in the zoogeography of this genus. Platorchestia is proposed to have arisen on Laurasia and is therefore basically a northern hemisphere genus. Questions concerning Platorchestia zoogeography and evolutionary ecology are posed and two methods (more intensive field sampling and molecular genetics) are suggested to be the way to solve them.     

Two new species of freshwater crabs from Mount Elgon,East Africa (Brachyura: Potamoidea: Potamonautidae) and a re-diagnosis of Potamonautes niloticus (H. Milne Edwards, 1837) with notes on their natural history and onchocerciasis

Two new species of potamonautid freshwater crabs from eastern Uganda, Africa are described, and Potamonautes niloticus (H. Milne Edwards, 1837) is re-diagnosed with key characters illustrated photographically. A total of four species of crabs are now known to occur on Mount Elgon, which borders both Kenya and Uganda. Two of these species are endemic to the mountain and the distribution patterns of all four species indicate a distinct altitudinal preference. All taxa are compared with similar species and their distributions and natural history are reviewed. Furthermore, three of the crabs recorded from Mount Elgon have been implicated in the transmission of onchocerciasis in East Africa.     

A new freshwater ostracod genus (Crustacea,Ostracoda) from Tokelau Islets,South Pacific Islands

Summary

Tungucypridopsis gen. nov. is described to include a species of freshwater ostracod which was originally described as Cypridopsis lairdi Victor and Fernando 1978 from Tokelau Islets, South Pacific Islands.     

Two new Mastigodiaptomus (Copepoda,Diaptomidae) from southeastern Mexico,with a key for the identification of the known species of the genus

Two new species of the freshwater planktonic copepod genusMastigodiaptomus—M. maya and M. reidae—are described from material collected in southeastern Mexico. This neotropical genus is known to be distributed mainly in the southern part of the United States, Mexico and Central America, and now embraces eight species. Of these, six occur in Mexico. Both new species seem to be closely related to M. texensis and M. albuquerquensis. It is probable that this group of Mexican species represents a northwards radiation from the Proto-Antilles-Central America region into the continent, eventually reaching North America. A key for the identification of the known species of the genus is provided.     

New freshwater interstitial Otoplanidae (Platyhelminthes: Proseriata) from the Paraná and Uruguay rivers,South America

This study describes two new freshwater otoplanid species (Platyhelminthes, Proseriata), Itaspiella parana n. sp. and Philosyrtis rauli n. sp., from interstitial habitats of the middle Paraná river (Argentina) and lower Uruguay river (Uruguay), respectively. Kata sp. from the Uruguay river is briefly characterized. This is the first report of otoplanids from freshwater environments of South America. The studied areas are particular biotopes. At present, only a few studies on the turbellarian fauna and its ecology have been carried out in the Paraná river and the records presented here are the first for the Uruguay river. The main difference between other known otoplanid species and Itaspiella parana, Philosyrtis rauli and Kata sp. is their ecological characterization. Until now the family Otoplanidae was known only from marine environments, with a few exceptions.     

A revision of the genus Platythelphusa A. Milne-Edwards, 1887 from Lake Tanganyika,East Africa (Decapoda: Potamoidea: Platythelphusidae)

The genus Platythelphusa is revised and six species are recognized. These species are P. armata A. Milne-Edwards, 1887, P. maculata (Cunnington, 1899), P. conculata Cunnington, 1907, P. tuberculata Capart, 1952, P. polita Capart, 1952 and P. echinata Capart, 1952. A seventh taxon, P. denticulata Capart, 1952 is considered here to be a junior synonym of P. conculata. A diagnosis for each species is provided and most are figured from the type. Keys to the families of African freshwater crabs and to the genus Platythelphusa are also provided.     

Redescription of the genus Noteochordodes,reinterpretation of Noteochordodes dugesi (Camerano, 1898), a new combination of Neochordodes talensis (Camerano, 1897) and a description of a new species

Three species of the freshwater genus Noteochordodes (Nematomorpha) have been reported from Argentina. In this reinvestigation Neochordodes talensis is included into Noteochordodes on the basis of its cuticular structure. The ultrastructural study of the holotype of N. dugesi showed features which are correspondent with the genus Pseudochordodes. Consequently, some specimens formerly assigned to this species have been assigned to a new species, Noteochordoeds cymatium. Another new species, Noteochordodes achosmosus is also described. Therefore, we regard five species to be valid for the genus Noteochordodes: N. achosmosus, N. cymatium, N. desantisi, N. talensis and N. saltae.     

A new species of Phyllodistomum (Digenea: Gorgoderidae) from Australian and New Zealand freshwater fishes with notes on the taxonomy of Phyllodistomum Braun, 1899

Phyllodistomum magnificum sp. nov., is described from the urinary bladder of Australian and New Zealand freshwater fish. Australian hosts were Anguilla reinhardtii, Tandanus tandanus, Hephaestus fuliginosus and Scortum hilli. New Zealand hosts were Anguilla australis and A. dieffenbachii. A presumed part of the life-cycle is described. Typical cystocercous cercariae are produced by sporocysts in the gills of a Pisidium species and are eaten by aquatic arthropods in which they encyst. The taxonomy of the genus Phyllodistomum is discussed and it is suggested that those species with cystocercous cercariae form a phylogenetic unit with Gorgodera, Gorgoderina, Progorgodera and Gorgotrema species.     

Species of Gyrodactylus von Nordmann, 1832 (Monogenea: Gyrodactylidae) from freshwater fishes in southern England,with a description of Gyrodactylus rogatensis sp. nov. from the bullhead Cottus gobio L.

Eleven species of Gyrodactylus were found infecting five species of freshwater fishes collected from Rogate (West Sussex, England). These were G. arcuatus and G. gasterostei from Gasterosteus aculeatus, G. pungitii from Pungitius pungitius, G. aphyae, G. laevis, G. limneus, G. macronychus and G. minimus from Phoxinus phoxinus, G. pavlovskyi and G. sedelnikowi from Noemacheilus barbatulus and G. rogatensis n.sp. from Cottus gobio. G. (Limnonephrotus) rogatensis is a member of the G. wageneri species group, and can be distinguished from closely related species (G. aphyae, G. pungitii and G. gasterostei) by its relatively long marginal hooks and by the abruptly tapering toes of its marginal hook sickles. Each parasite was collected from a single host species, and each was narrowly site-specific. With the exception of G. rogatensis, all of the gyrodactylids collected at Rogate also occur in Continental Eurasia, suggesting that they colonized Britain with their hosts via the Doggerland land bridge after the Devensian glaciation. This study demonstrates both the potential of Gyrodactylus for studies of parasite-host coevolution, and the need for critical taxonomic analysis of members of the genus.     

XV.—Information respecting botanical travellers

Summary

A new species of mysid, Parvimysis pisciscibus, is described from leaf litter banks in the Igarapé Tarumazinho, a freshwater side stream of the Rio Negro, Brazil. This small species is the first freshwater mysid to be described from the Amazon basin.     

A new genus of freshwater crab (Crustacea: Decapoda: Brachyura: Potamidae) from Thailand,with a description of a new species

A new genus, Stelomon, is established for the Thai freshwater crabs Potamon kanchanaburiense Naiyanetr, 1992, and P. pruinosum Alcock, 1909. The unique structure of the male first pleopod is the key diagnostic generic character. One new species, which differs in the form of the male first pleopod, is also described. A key to the species of Stelomon is included.     

A new species of the genus Cytheridella (Crustacea,Ostracoda) from Nigeria,West Africa

Cytheridella tepida sp. nov., a freshwater ostracod, is described from Nigeria, West Africa. It has been compared with five extant species of the genus Cytheridella. Cytheridella tepida was collected from slow-flowing streams characterized by warm water. Some other ecological notes on its habitat are given.     

Redescription of three cyclocypridine freshwater ostracods (Crustacea,Ostracoda) from Southeast Asia

Summary

All three species of cyclocypridine freshwater ostracods, Cypria javana Müller, 1906, Cypria spinifera Tressler, 1937 and Physocypria crenulata (Sars) 1903 presently known from Southeast Asia are redescribed. Valves, appendages and internal organs are illustrated for females and males and detailed remarks are given for all the species.     

Terrapotamon gen. nov., a new genus of freshwater crabs from Malaysia and Thailand,with description of a new species,Terrapotamon aipooae sp. nov. (Crustacea: Decapoda: Brachyura: Potamidae)

A new genus, Terrapotamon gen. nov., is established to accomodate two species of freshwater crabs, Potamon abbotti Rathbun, 1898 from southern Thailand, and a new species, Terrapotamon aipooae sp. nov. from West Malaysia. Members of this genus are characterized by their inflated carapaces, very acutely triangular external orbital angles, and structure of their first male gonopods.     

Genetic diversity of freshwater crabs (Brachyura: Sesarmidae) from central Jamaica with description of a new species

Jamaica is the only island of the Greater Antilles where freshwater streams are not populated by representatives of the old lineage of freshwater crabs, the Pseudothelphusidae. Instead, a very diverse fauna of endemic sesarmid crabs inhabits freshwater and terrestrial habitats throughout the island, thereby showing complete independence from the sea. They have been reported thriving in bromeliad leaf axils, rock rubble, empty snail shells, caves and mountain streams. Otherwise, the Sesarmidae are typical inhabitants of soft‐sediment littoral habitats like marshes and mangroves. For many years, crabs from Jamaican mountains streams had been considered to belong to a single species, Sesarma bidentatum Benedict . However, recent morphological and molecular studies have shown that crabs from mountain streams of different regions of the island belong to different species. Consequently, four new crab species have been described over the last 10 years. In this study, we give evidence that freshwater streams in central Jamaica also host two different species of crabs. In streams draining to the north we exclusively found the species S. windsor Türkay and Diesel, , while streams draining to the south were inhabited by a closely related but undescribed species of crab. The southern species is here described as new and is referred to as Sesarma meridies sp. n. Morphological and molecular (12S and 16S mtDNA) evidence is provided that allows these two species of freshwater crabs from central Jamaica to be distinguished. The species richness of Jamaican endemic sesarmids thereby increases to 10, which makes the island unique in terms of its diversity of land‐dwelling crabs.