Drought Coincided with, but Does Not Explain, Late Holocene Megafauna Extinctions in SW Madagascar

Climate drying could have transformed ecosystems in southern Madagascar during recent millennia by contributing to the extinction of endemic megafauna. However, the extent of regional aridification during the past 2000 years is poorly known, as are the responses of endemic animals and economically important livestock to drying. We inferred ~1600 years of climate change around Lake Ranobe, SW Madagascar, using oxygen isotope analyses of monospecific freshwater ostracods (Bradleystrandesia cf. fuscata) and elemental analyses of lake core sediment. We inferred past changes in habitat and diet of introduced and extinct endemic megaherbivores using bone collagen stable isotope and 14C datasets (n = 63). Extinct pygmy hippos and multiple giant lemur species disappeared from the vicinity of Ranobe during a dry interval ~1000–700 cal yr BP, but the simultaneous appearance of introduced cattle, high charcoal concentrations, and other evidence of human activity confound inference of drought-driven extirpations. Unlike the endemic megafauna, relatively low collagen stable nitrogen isotope values among cattle suggest they survived dry intervals by exploiting patches of wet habitat. Although megafaunal extirpations coincided with drought in SW Madagascar, coupled data from bone and lake sediments do not support the hypothesis that extinct megafauna populations collapsed solely because of drought. Given that the reliance of livestock on mesic patches will become more important in the face of projected climate drying, we argue that sustainable conservation of spiny forests in SW Madagascar should support local livelihoods by ensuring that zebu have access to mesic habitat. Additionally, the current interactions between pastoralism and riparian habitats should be studied to help conserve the island’s biodiversity.

Seed Shrimp, Mussel Shrimp (Freshwater Ostracods) scientific name: (Crustacea: Ostracoda: Podocopa)

Ostracods are a class of small crustaceans that inhabit both saltwater and freshwater environments. There are approximately 8,000 living species of ostracods. Non-marine ostracods belong to the Order Podocopida, which is comprised of the superfamilies Cypridoidea, Darwinuloidea, and Cytheroidea (Thorp 2015). They are commonly known as seed shrimp due to their small size, typically smaller than a poppy seed or up to 1 mm. Their carapace, the upper shell of crustaceans, is bivalved, giving it the common name mussel shrimp.

Evidence of Predation on Early Pleistocene Freshwater Ostracods (Umbria, Central Italy)

Although drillholes in modern and ancient ostracods are known, the record is relatively scarce when compared to other taxa, and mainly exist with reference to the marine environment. Moreover, less is known about perforated ostracods, and more generally, about bioerosion in freshwater environments. Traces of predation on freshwater ostracods are reported for the first time in deep-lake deposits belonging to the early Pleistocene Fosso Bianco Unit, and outcropping in the Cava Nuova section (Umbria, central Italy). Deposits are mainly clay to silty clay and sand; the fossil record is sparse, and is mainly comprised of very rare gastropods and bivalves, ostracods and plant remains (leaves, seeds and wood’s fragments). The association of ostracods consists of Candona (Neglecandona) neglecta, Caspiocypris basilicii, Caspiocypris tiberina, Caspiocypris perusia, Caspiocypris tuderis, Caspiocypris posteroacuta, and Cyprideis torosa. The Caspiocypris group, considered to be endemic to the grey clays of the Fosso Bianco Unit, present the majority of specimens affected by predation, with a prevalence of predated female valves and a comparable number of right and left predated valves, while only a few of Candona(N.) neglecta (adult and juvenile) valves are perforated. Traces of predation for nourishment, represented by microborings of different types, were abscribed to the ichnospecies Oichnus paraboloides Bromley 1981, Oichnus simplex Bromley 1981, Oichnus gradatus Nielsen and Nielsen 2001, Oichnus ovalis Bromley 1993, and Dipatulichnus rotundus Nielsen and Nielsen 2001. Microboring affected both adult and juvenile specimens, evidencing prey–predator coexistence in the same environment over a long period of time. This report makes a fundamental contribution to the knowledge of predation in this peculiar confined environment, also suggesting prey–predator relations over a relatively short time interval (80–160 ka).

Freshwater ostracods (Crustacea) from Hainan Island, southern China, with description of a new species

In this study, 24 non-marine ostracod species were found in 142 samples collected from diverse water bodies from Hainan Island, south China. Among them, a new species Pseudocypretta lineata n. sp. is described and illustrated. Twelve species are new records for China. Among them, six species are identified: Microdarwinula zimmeri (Menzel, 1916), Pseudocypretta lineata n. sp., Pseudostrandesia mamarilorum (Victor & Fernando, 1981c), Stenocypris malayica Victor & Fernando, 1981b, Stenocypris orientalis Victor & Fernando, 1981b and Strandesia freyi Victor & Fernando, 1981c. Six species are left in open nomenclature: Batucypretta sp., Candonopsis? sp., Cypridoidea gen. et sp. indet. 1, Cypridoidea gen. et sp. indet. 2, Cyprinotus cf. kimberleyensis McKenzie, 1966 and Vestalenula sp. Additionally, a re-description of Strandesia freyi is provided.

New records of freshwater ostracoda from the xingyun lake

<p>This present paper reports eight modern ostracode collected from the bottom of the Xingyun Lake,Yunnan Province, including Candonocypris novaezelandiae (Baird, 1843), mateless cyclocypris Cypridopsis Vidua (O.F.M ller, 1776), star (which really wedge dielectric) Eucypris CF. Cuneata (Tsao, 1959), Cleveland star kraeplini (G.W.M mediated Cypris ller, 1903) Belgium, sheshi (similar) glass dielectric Schellencandona CF. Belgica (Klie, 1937), Fabaeformiscandona subacuta (Yang, 1982), unarmed mobs mediated Cetacella inermis (Martin, 1958), the Yunnan flower (compare kinds) Yunnanicyhere cf.reticulate mediated gen.etsp.nov. the true star (dielectric wedge comparison of three) Eucypris CF. Cuneata (Tsao, 1959), unarmed mobs mediated Cetacella inermis (Martin, 1958) and Yunnan (a comparison of dielectric reticulate flowers) Yunnanicyhere cf.reticulate gen.etsp.nov.  these species are newly recorded from modern lakes.It has enriched the understanding of freshwater ostracoda of the biological communities in China.</p><p><strong>Key word</strong><strong> </strong> freshwater ostracods; Xingyun Lake; Yunnan Province</p>

Distribution of Recent non-marine ostracods in Icelandic lakes, springs, and cave pools

Ostracods in Icelandic freshwaters have seldom been researched, with the most comprehensive record from the 1930s. There is a need to update our knowledge of the distribution of ostracods in Iceland as they are an important link in these ecosystems as well as good candidates for biomonitoring. We analysed 25,005 ostracods from 44 lakes, 14 springs, and 10 cave pools. A total of 16 taxa were found, of which seven are new to Iceland. Candona candida (Müller, 1776) is the most widespread species, whereas Cytherissa lacustris (Sars, 1863) and Cypria ophtalmica (Jurine, 1820) are the most abundant, showing great numbers in lakes. Potamocypris fulva (Brady, 1868) is the dominant species in springs. While the fauna of lakes and springs are relatively distinct from each other, cave pools host species that are common in both lakes and springs. Icelandic non-marine ostracods include mostly generalist species, as well as species adapted to cold climates and resemble those of other north European countries while sharing very few species with the North American Arctic. Iceland is experiencing impacts from climate change and a booming tourism. It is possible to use selected freshwater ostracods as biomonitoring tools by constructing a detailed database of these species.

A historical review of the taxonomy and classification of Entocytheridae (Crustacea: Ostracoda: Podocopida)

Ostracods of the family Entocytheridae are obligate ectosymbionts of other crustaceans, including crayfishes, isopods, amphipods, and a species of freshwater crab. Entocytheridae, with five subfamilies, 35 genera, and 213 currently accepted species, represents one the most diverse groups of extant freshwater ostracods. Here, we present the results of an extensive literature review, documenting the often complex historical taxonomic activity and resulting classification of Entocytheridae. This overview highlights inconsistencies, errors, and additional sources of confusion that have been inadvertently introduced into the literature, a number of which have remained uncorrected for decades. Also provided is a comprehensive checklist of taxonomic nomenclature and a list of currently accepted names in Entocytheridae.

A humid early Holocene in Yemen interpreted from palaeoecology and taxonomy of freshwater ostracods

Lake or marsh sediments in the Qa'a Jahran–Dhamār area indicate a period of higher moisture availability in the early Holocene of the highlands of Yemen. Forty-two marl–peat sediment samples from eight stratigraphic sections of that area have been collected and are examined for the first time for their ostracod associations. Eight species belonging to seven genera and four families are reported. Their ecological tolerances and preferences are used to investigate the climatic and environmental changes in the early to mid-Holocene. Our data are compared and correlated with previous archaeological results, particularly from the region of Qa'a Jahran (Dhamār) in the vicinity of the village of Beyt Nahmi. We conclude that the wettest period of the Holocene was from about 7900 to 7400 cal yr BP, when northwards incursion of the Indian Ocean Monsoon caused intensified monsoon precipitation over southern Arabia.