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We present an updated, subjective list of the extant, non-marine ostracod genera and species of the world, with their distributions in the major zoogeographical regions, as well as a list of the genera in their present hierarchical taxonomic positions. The list includes all taxa described and taxonomic alterations made up to 1 July 2018. Taxonomic changes include 17 new combinations, 5 new names, 1 emended specific name and 11 new synonymies (1 tribe, 4 genera, 6 species). Taking into account the recognized synonymies, there are presently 2330 subjective species of non-marine ostracods in 270 genera. The most diverse family in non-marine habitats is the Cyprididae, comprising 43.2% of all species, followed by the Candonidae (29.0%), Entocytheridae (9.1%) and the Limnocytheridae (7.0%). An additional 13 families comprise the remaining 11.8% of described species. The Palaearctic zoogeographical region has the greatest number of described species (799), followed by the Afrotropical region with 453 species and the Nearctic region with 439 species. The Australasian and Neotropical regions each have 328 and 333 recorded species, respectively, while the Oriental region has 271. The vast majority of non-marine ostracods (89.8%) are endemic to one zoogeographical region, while only six species are found in six or more regions. We also present an additional list with 'uncertain species', which have neither been redescribed nor re-assessed since 1912, and which are excluded from the main list; a list of taxonomic changes presented in the present paper; a table with the number of species and % per family; and a table with numbers of new species described in the 20-year period between 1998 and 2017 per zoogeographical region. Two figures visualize the total number of species and endemic species per zoogeographical region, and the numbers of new species descriptions per decade for all families and the three largest families since 1770, respectively.
The genus Bennelongia De Deckker & McKenzie, 1981 is most likely endemic to Australia and New Zealand and, up to now, only two described species in this genus had been reported from Western Australia. Extensive sampling in Western Australia revealed a much higher specifi c diversity. Here, we describe nine new species in three lineages, within the genus Bennelongia: B. cygnus sp. nov. and B. frumenta sp. nov. in the B. cygnus lineage, B. gwelupensis sp. nov., B. coondinerensis sp. nov., B. cuensis sp. nov., B. lata sp. nov. and B. bidgelangensis sp. nov. in the B. australis lineage, and B. strellyensis sp. nov. and B. kimberleyensis sp. nov. (from the Pilbara and Kimberley regions respectively) in the B. pinpi-lineage. For six of the nine species, we were also able to construct molecular phylogenies and to test for cryptic diversity with two different methods based on the evolutionary genetic species concept, namely Birky’s 4 x rule and the GYMC model. These analyses support the specifi c nature of at least four of the fi ve new species in the B. australis lineage and of the two new species in the B. pinpi lineage. We also describe Bennelongiinae n.subfam. to accommodate the genus. With the nine new species described here, the genus Bennelongia now comprises 15 species, but several more await formal description.
Five new species in four new genera from Western Australia are described. All species have valve characters that are reminiscent of the genus Heterocypris Claus, 1892 and also have similar valve outlines, with highly arched valves. However, all species have a hemipenis morphology that is totally different from the typical form in Heterocypris. In Patcypris gen. nov. (with type species P. outback gen. et sp. nov.), the lateral lobe is large and shaped as a pickaxe, while the medial lobe is divided into two distal lobes. Trilocypris gen. nov. (with type species T. horwitzi gen. et sp. nov.) is characterised by a hemipenis that has three, instead of two, distal lobes. In Bilocypris gen. nov. (with type species B. fortescuensis gen. et sp. nov. and a second species, B. mandoraensis gen. et sp. nov.), the lateral lobe of the hemipenis is spatulate, rather than boot-shaped, and the medial lobe is bilobed. Billcypris gen. nov. (with type species B. davisae gen. et sp. nov.) has a large and sub-rectangular lateral lobe and a pointed medial lobe. We discuss the taxonomic value of the traditional and new morphological characters and speculate that the diversity of this cluster of genera and species may be greater than currently known.
The Sergipe-Alagoas Basin has one of the most complete, exposed lithological successions of the Cretaceous period in the continental margin of Brazil. It captures several phases of the evolution of the South Atlantic Ocean, including rift, gulf and drift. The upper Aptian–Albian Riachuelo Formation corresponds to the first stages of the southern proto-Atlantic Ocean invasion in that basin. The present study reviews the taxonomic identification and ecology of 39 ostracod species of this formation, proposing a new genus – Gabonorygma gen. nov. – and three new species – Praebythoceratina deltalata sp. nov., Gabonorygma sergipana gen. et sp. nov. and Brachycythere smithsoniana sp. nov. Other taxa include Conchoecia? sp. 1, Cytherella sp. 1, C. besrineensis comb. nov., Cytherelloidea aff. globosa, C. btaterensis, Bairdoppilata sp. 1, Bairdoppilata sp. 2, B. comanchensis comb. nov., B. pseudoseptentrionalis, Robsoniella falklandensis, Cetacella sp. 1, Paracypris eniotmetos, Harbinia sinuata?, H. crepata, Liasina sp. 1, Praebythoceratina amsittenensis comb. nov., P. trinodosa comb. nov., Patellacythere sp. 1, P. shimonensis comb. nov., Xestoleberis? sp. 1, Xestoleberis? sp. 2, Apatocythere? sp. 1, Neocythere? aff. pseudovanveeni, N. (Physocythere) tenuis, Aracajuia antiqua comb. nov., A. benderi, A. fragilis comb. nov., Eocytheropteron sp. 1, Metacytheropteron aff. minuta, Microceratina? sp. 1, M. azazoulensis, Veenia guianensis, Algeriana? sp. 1, Quasihermanites? sp. 1 and Sergipella viviersae.