Delicata chongqingensis Wei Zhang, S. Q. Yang & S. Blanco 2019, sp. nov.
Creators: name: Yang, Song-Qi
name: Zhang, Wei
name: Blanco, Saùl
name: Jüttner, Ingrid
name: Wu, Zhong-Xing
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Chromista
Ochrophyta
Bacillariophyceae
Cymbellales
Cymbellaceae
Delicata
Delicata chongqingensis

description: Delicata chongqingensis Wei Zhang, S.Q.Yang & S. Blanco sp. nov. (Figs 2–25)
LM: Valves moderately dorsiventral, semi-lanceolate, dorsal margin evenly and moderately arched, ventral margin straight in the central section. Slightly protracted, rounded valve ends (Figs 2–11). Length of the observed specimens 21.0–30.5 μm, width 6.0–8.3 μm, length/width ratio 2.9–4.0, median 3.5 (n=32). Axial area narrow, curved, not or slightly ventrally displaced. Dorsally central area forming a large, irregular semifascia, bordered on the dorsal side by 2–4 shortened central striae of different length. Raphe not or slightly ventrally displaced, distinctly lateral, becoming filiform near the distal ends and reverse-lateral near the proximal ends. On the ventral side in the valve centre striae slightly radiate or more or less parallel, sometimes slightly wider spaced, slightly radiate away from the centre and often becoming more or less parallel close to the apices. On the dorsal side shortened striae wider spaced, more or less parallel or slightly radiate. Away from the centre striae slightly radiate throughout the valve. Areolae not discernable in LM. Striae 11–15 in 10 μm, mostly 11–13 in 10 μm dorsally, 13–15 in 10 μm ventrally, slightly denser towards the ends (16–18 in 10 μm).
SEM: Proximal raphe branches curved to the ventral side terminating in small central pores that are slightly ventrally deflected (Figs 12–17). Distal raphe fissures hooked towards the dorsal side (Figs 12, 13, 18, 19). Striae composed of tilde-shaped or sigmoid areolae (Figs 12–19) extending around the apices and onto the mantle. Three to four rounded or slit-like, isolated areolae are present on the ventral side near the central nodule (Figs 14–17). Narrow linear axial area widening towards the semifascia in the valve centre. Raphe continuous internally, distally raphe ends terminating in small, knob-like helictoglossae which are offset and bent very slightly towards the dorsal margin (Figs 20–22). Ventrally, one or two slit-like internal openings, marked by small marginal nodules, at the end of the central striae adjacent to the central area (Figs 23, 24). Striae constitute alveoli internally, with oval or tilde-shaped internal areola openings (Figs 21–25).
Type: — CHINA. Chongqing municipality, Daning River, 31° 39′ 42′′ N, 109° 27′ 50′′ E, elevation 680 m a.s.l., coll. Z.X. Wu, 20 April 2013 (holotype: slide DNR-1, illustrated in Fig. 8).
Etymology: —The specific epithet “ chongqingensis ” refers to the place from which the species is described.
description: Published as part of Yang, Song-Qi, Zhang, Wei, Blanco, Saùl, Jüttner, Ingrid & Wu, Zhong-Xing, 2019, Delicata chongqingensis sp. nov., a new cymbelloid diatom species (Bacillariophyceae) from Daning River, Chongqing, China, pp. 57-66 in Phytotaxa 393 (1) on page 59, DOI: 10.11646/phytotaxa.393.1.5, http://zenodo.org/record/13718079