Morphology, ultrastructure and distribution of Placoneis itamoemae sp. nov. (Cymbellaceae) from Brazil Straube, Arielli Tremarin, Priscila Izabel Castro-Pires, Emanuela Cristina De Marquardt, Gisele Carolina Ludwig, Thelma Alvim Veiga Phytotaxa 2013 2013-01-15 76 3 55 62 Straube, Tremarin & Ludwig Straube, Tremarin & Ludwig 2013 [151,839,1406,1435] Bacillariophyceae Cymbellaceae Placoneis GBIF Chromista Cymbellales 1 56 Bacillariophyta species itamoemae sp. nov.   Type:—  BRAZIL. Paraná: Balsa Nova County, Papagaios river, 25°27'55"S, 49°45'58"W, January/2001, UPCB 44567- diatom collection of the Botany Department, Universidade Federal do  Parana; holotypeslide UPCB 44567, designated here in Fig. 3; isotype slide ANSP GC 26818( Academy of Natural Sciences, Philadelphia). Valves elliptic-lanceolate, length 26.0– 37.9 µmand breadth 10.0– 13.4 µm(n=47), with rostrate ends. Raphe sternum straight and narrow, central area slightly expanded, formed by 5–6 irregularly shortened median striae on either side of the raphe, 1–3 (usually 2) rounded isolated pores on one side of the central area. Central pores more expanded internally, located on the prominent central nodule. Raphe straight with proximal ends externally slightly expanded, rounded and internally deflected to the side of central pores; distal ends turned into opposite directions and each one with distinct morphology, hooked-like at one end of the valve and gradually curved at the other. Internally, the distal raphe ends terminate in small helictoglossae. Striae radiate, arched in the middle portion of valve, becoming parallel to convergent at the apices, 17–21 in 10 µm, extending onto the valve mantle, formed by one row of rounded to elliptical areolae, 36–39 in 10 µm. Etymology:—This species is named in honor of Dr. Ita Moema Valente-Moreira, a retired diatom researcher from Universidade Federal do Paraná.   FIGURE 1–14.Morphological variation of  Placoneis itamoemae, LM, scale = 10 µm. Note the exemplars with different numbers of pores in the central area (Figs 8–10).  Ecological data:—The collected sample from Papagaios river showed high temperature (22.5ºC), slightly acid conditions (pH 6.7), 102.8 µS.cm -1of conductivity and 1.52 mg/L of dissolved oxygen ( Visinoni 2002). 3313798301 UPCB Brazil Balsa Nova County -25.465279 Papagaios river 21 -49.76611 1 56 UPCB 44567 1 Parana 3313798302 ANSP Brazil Academy of Natural Sciences 1 56 UPCB 44567, GC 26818 1 Parana holotype