Candona angulata ( Müller, 1900 )

RAUSCH, LEA, STOICA, MARIUS & LAZAREV, SERGEI, 2020, A Late Miocene - Early Pliocene Paratethyan Type Ostracod Fauna From The Denizli Basin (Sw Anatolia) And Its Palaeogeographic Implications, Acta Palaeontologica Romaniae 16 (2), pp. 3-56 : 11

Candona angulata ( Müller, 1900)

Fig. 7 a-l

1900 Candona angulata n. sp. Müller, p. 18, pl. I, fig. 1- 17.

1990 Candona angulata Müller - Fuhrmann & Pietrzeniuk, p. 209, pl. 4, fig. 6-9.

2000 Candona angulata Müller- Meisch, p. 87, fig. 31A-E.

2005 Candona angulata Müller- Viehberg, p. 65, fig. 6, 13.

2008 Candona angulata Müller- Fuhrmann, pl. 2, Fig. 6 a-d.

2012 Candona angulata Müller- Fuhrmann, p. 24, pl. 6, fig. 1a-f, 2a-d.

Description. The carapace, usually distinctly elongated, has a similar shape to that of C. neglecta in lateral view. Only the posterior expansion of the LV is slightly more pointed and expanded, varying from a rounded to a toothshaped curvature. The RV in contrast lacks this expansion and sculpts only a weak ankle to the concave ventral margin. The LV overlaps the RV at both ends. The valves surface is smooth. The inner lamella is well developed and slightly broader in the anterior. It continues along the ventral margin and numerous, close-set and curved pore canals are present. The muscle scar forms a row of three scars with a larger elongated one above. The male carapace is larger and higher than that of the compressed female and has a more pronounced ventral concavity. Dimension: L = 0,86 – 1,72 mm, H = 0,27 – 1,01 mm, the minimum sizes include juveniles too.

Chronostratigraphical and geographical distribution. The species is well known from coastal regions of Ireland, UK, Belgium, Netherlands, Poland, Russia (Volga Basin) and North Africa ( Meisch, 2000). It has been described from the southern Balkans (Lake Dojran; Petkovski, 1958) as C. angulata meridionalis and northern Africa, where populations described by Gauthier (1928), according to Meisch (2000) should also belong to the same species. It has further been reported from Pleistocene deposits from Central and Northern Germany ( Fuhrmann, 2012; Viehberg, 2005). Within Section B, C. angulata is the most common occurring species.

Ecology. Living representatives of this halo-tolerant species prefer slightly salty water and have often been observed in brackish coastal ponds, ditches and river mouths with salinities ranging from 0,2 - 14‰ ( Meisch, 2000).

Figures

Fig. 7a-l Candona angulata; a LV, external view, ♀; b RV, external view, ♀; c LV, external view, ♂; d RV, external view, ♂; e Carapace, view from RV, ♀; f, h RV, internal view, ♂; g LV, internal view, ♂; i RV, external view, A2 juvenile; j LV, external view, A3 juvenile; k RV, external view, A3 juvenile; l RV, external view, A4 juvenile; (all specimens from section B, sample 10 m).

Fig. 6a-h Caspiocypris carica; a, c LV, external view; b, d RV, external view; e LV, internal view; f RV, internal view; g LV, external view, A1 juvenile; h RV, external view, A1 juvenile; (all specimens from section A, samples 0 m – 35,5 m).