Stauroneis boyntoniae Bahls, 2013

Bahls, Loren, 2013, New diatoms (Bacillariophyta) from western North America, Phytotaxa 82 (1), pp. 7-28 : 21-22

Stauroneis boyntoniae Bahls , sp. nov. ( Figs 85–89 )

Valves broadly lanceolate with narrow subrostrate to apiculate apices. Valve length 31–52 µm; valve width 7.6–10.6 µm. Axial area narrow. Stauros narrow but wider than the axial area, rectangular. Raphe lateral with straight, weakly expanded proximal ends. Striae weakly radiate near the valve center, more strongly radiate toward the apices, 28–32 in 10 µm. Areolae transapically oblong and irregularly spaced, 24–30 in 10 µm.

Holotype: — USA, Wyoming: Sublette County, Lower Twin Lake , 43.1242 o N, 109.7328 o W, elev. 3154 m, coll. B. Boynton, 26 August 2012. MDC sample 496801; holotype slide MDC 41-65 ( Figs 85–89 ) (circled holotype specimen in Fig. 86 ). MONTU!

Isotypes: —MDC slide 126-59 ( MONTU!); circled specimens on ANSP! GC 65167.

Etymology:—This species is named after Beverly Boynton, a volunteer with Adventurers and Scientists for Conservation and collector of the holotype sample.

Observations:— Stauroneis boyntoniae belongs to the group of Stauroneis species with small to medium valves, fine striae, and transapically oblong and irregularly spaced areolae ( Bahls 2010). Stauroneis neohyalina Lange-Bertalot & Krammer in Lange-Bertalot & Metzeltin (1996: 104) has narrower valves (6–9 µm) and higher stria density (32–40 in 10 µm). Stauroneis siberica (Grunow) Lange-Bertalot & Krammer in Lange-Bertalot & Metzeltin (1996: 104) has more elliptic and larger valves (54–68 µm long by 12–16 µm wide) with more abruptly protracted apices.

Distribution and Ecology: — Stauroneis boyntoniae is known only from the type locality, a lake high in the Wind River Range of Wyoming. Environmental data are not available for this lake, but it is presumed to have low concentrations of nutrients and dissolved solids.

Genus Craticula A. Grunow 1867: 20

Figures

FIGURES 85–89: Stauroneis boyntoniae from Lower Twin Lake, Sublette County, Wyoming (type locality). Fig. 86: Holotype specimen. Scale bars: 10 µm.