Achnanthidium tirolense, Jüttner & Hamilton & Wetzel & De & Vijver & King & Kelly & Williams & Ector, 2022

Jüttner, Ingrid, Hamilton, Paul B., Wetzel, Carlos E., De, Bart Van, Vijver, King, Lydia, Kelly, Martyn G., Williams, David M. & Ector, Luc, 2022, A study of the morphology and distribution of four Achnanthidium Kütz. species (Bacillariophyta), implications for ecological status assessment, and description of two new European species, Cryptogamie, Algologie 20 (10), pp. 147-176 : 156

publication ID	https://doi.org/ 10.5252/cryptogamie-algologie2022v43a10
DOI	https://doi.org/10.5281/zenodo.7819402
persistent identifier	https://treatment.plazi.org/id/3B1887D1-FF90-FFED-FEBF-86FAFBD2F819
treatment provided by	Felipe
scientific name	Achnanthidium tirolense
status	sp. nov.

Treatment

Achnanthidium tirolense sp. nov.

( Figs 15 View FIG ; 16 View FIG )

HOLOTYPE. — Austria. Plansee , 18.IV.2019, I. Jüttner (holo-, NMW [ NMW.C.2021.06.2019]; iso-, BM, BR, CANA).

TYPE LOCALITY. — Austria. Tyrol, Kleiner Plansee, Plansee, 47°28’34.756”N, 10°46’50.861”E.

HABITAT. — Epiphytic and epilithic in lake littoral.

ETYMOLOGY. — The species was named after the region where it was found, Tyrol, Austria.

REGISTRATION. — http://phycobank.org/103379

DESCRIPTION

LM ( Fig. 15 View FIG A-AG)

Valves rhombic-lanceolate with slightly inflated valve centre. Margins tapering gradually towards long protracted, broadly rounded, rostrate poles. Valve dimensions (n = 25): length 14-23.5 µm, width at valve centre 3-4 µm. Central area on RV an acute-angled fascia. Raphe filiform, straight. Central pores slightly expanded, distantly placed at margin of central area. Central area on RL narrow lanceolate, sometimes a narrow acute-angled fascia on one or both sides formed by more widely spaced central striae. Axial area narrow linear on both valves. Striae radiate throughout on both valves, 28-30 in 10 µm (RV and RL).

SEM ( Fig. 16 View FIG A-F)

Raphe located on slightly raised sternum, central raphe endings small, round, terminal raphe fissures straight with tear drop-shaped ends, terminating at valve/mantle junction. Internally, central raphe endings slightly deflected to opposite sides, terminal raphe endings form small helictoglossae. Striae straight or slightly curved, on RV composed of 3-5 areolae, on RL composed of 2-5 areolae. Areolae round, those adjacent to valve margin round or slit-like. One row of transapically elongated areolae on mantle separated from areolae on valve face by a hyaline area.