Recent Freshwater Ostracods of the World Crustacea, Ostracoda, Podoc
Their story began 500 million years ago, but we only started to get to know them in 1746, when Linné described the first ostracod species. Vividly portraying the freshwater ostracods, this comprehensive reference work gathers the knowledge gained during s
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According to Liebau (2005), the suborder Cytherocopina is subdivided into two infraorders: Archaeocytherinina Liebau 1991 and Nomocytherinina Liebau 1991. However, at least three superfamilies cannot fit into either of the proposed infraorders, so this systematic division is not widely accepted and will not be considered here. Suborder Cytherocopina contains about 15 superfamilies, most of which are known only after fossils, and only the superfamily Cytheroidea has representatives in freshwater ecosystems. Diagnosis (after Horne et al. 2002): Carapace mostly 1 mm long or less, shape extremely variable (elongate, quadrate, round, etc.) (Figs. 1 and 2). Valves smooth or strongly ornamented with spines, nodes, ridges, alae, etc. (Figs. 1–3). Valves usually with well-developed fused zone and CIL, often with selvages and lists. Hinge well developed, complex, and rarely adont (Fig. 4). CMS pattern consists of four or five scars in a vertical row (Figs. 5a, b and 6b). Sieve pores present (Fig. 6a) or absent. Females with seven pairs of appendages, UR reduced. A1 5- to 7-segmented (Figs. 8 and 6e). Exopod on A2 representing a segmented or unsegmented spinneret seta connected to a gland at the base of the limb, sometimes sexually dimorphic (Fig. 7). Md vibratory plate with up to seven setae (Fig. 9). Mxl with a large vibratory plate (Fig. 10) bearing .unreflexed setae and up to four reflexed setae. Male brush-shaped organ present (Fig. 11d). L5, L6, and L7 walking legs, sometimes sexually dimorphic (Figs. 12 and 6c, d, g). Hemipenis with sperm pump incorporated (no Zenker organ) (Figs. 13, 14, 6d). In males, UR incorporated in hemipenis. Females sometimes with extended posterior brood chamber. The following families are represented in the freshwater ecosystems: Cytherideidae, Entocytheridae, Kliellidae, Leptocytheridae, Limnocytheridae, and Loxoconchidae. In the publication of Martens et al. (2007), families Cytheruridae and Xestoleberididae were included in the list of ostracod families with recent freshwater representatives. However, all these species have been found in highly saline waters, such as marine bays, estuarine waters, mangroves, and at the most brackish waters; therefore, they are not included in this book.
I. Karanovic, Recent Freshwater Ostracods of the World, DOI 10.1007/978-3-642-21810-1_3, # Springer-Verlag Berlin Heidelberg 2012
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Superfamily Cytheroidea Baird 1850 (Suborder Cytherocopina Gr€ undel 1967)
Fig. 1 SEM: (a, b, c) Limnocythere inopinata (Baird 1843a); (d, e) Metacypris cordata Brady and Robertson 1870; (f) Leucocythere mirabilis Kaufmann 1892; (g) Cytherissa lacustris Sars 1863: (a, f) lateral view from the left side; (b) dorsal view; (c, d) ventral view; (e, g) lateral view from the right side. Photos: D. Keyser
Superfamily Cytheroidea Baird 1850 (Suborder Cytherocopina Gr€ undel 1967)
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Fig. 2 SEM: (a) Gomphocythere sp.; (b) Cytheridella sp.; (c) Paralimnocythere karamani (Petkovski 1960a); (d, e) Cytheromorpha fuscata (Brady 1869); (f, g) Loxoconcha elliptica Brady 1868; (h) L
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