The genus Luticola (Bacillariophyta) on Ile Amsterdam and Ile Saint-Paul (Southern Indian Ocean) with the description of two new species
Author
Chattová, Barbora
Author
Lebouvier, Marc
Author
Haan, Myriam De
Author
Vijver, Bart Van De
text
European Journal of Taxonomy
2017
2017-12-22
387
1
17
journal article
31098
10.5852/ejt.2017.387
d65d51d3-dda3-4bad-9d80-8fcb46a782f7
1133653
Luticola subcrozetensis
Van de Vijver, Kopalová, Zidarova & Levkov
Figs 13‒26
Diatoms of Europe: Diatoms of the European Inland Waters and Comparable Habitats
7: 228, pl. 46 figs
15‒31, pl. 47 figs 4‒6 (
Levkov
et al.
2013
).
Figs 13–26.
Luticola subcrozetensis
Van de Vijver
et al.
Light
(LM) and scanning electron micrographs (SEM) of a population from Ile Saint-Paul.
13–22
. LM of valve face views.
23–24
. SEM of external view showing composition of striae and typical raphe structure.
25–26
. SEM girdle view. Scale bars: 13‒22 = 10 µm; 23‒26 = 5 µm.
Type
ILE
DE LA POSSESSION:
Crozet Archipelago
, sub-Antarctica,
5 Dec. 1999
,
B
.
Van de Vijver
(holo-: slide no.
BR
‒4290; iso-: slides
BRMZU9
/25,
MKNDC
006278
/
B
).
Description
Light microscopy (
Figs 13–22
)
Valves rhombic-lanceolate to elliptic-lanceolate and even elliptic in smaller specimens with clearly convex margins and broadly rounded, non-protracted apices. Valve dimensions (n = 25): length 12‒ 29 µm, width 7.0‒8.5 µm. Axial area linear, slightly widening towards apices and central area. Central area bow-tie shaped, wider opposite the isolated pore, bordered by shortened striae on both sides. An isolated pore present in the central area, located halfway between the valve centre and the valve margin. Raphe branches straight, bent away from the isolated pore at both proximal and distal ends. Striae radiate throughout the entire valve,
15‒17 in
10 µm.
Scanning electron microscopy (
Figs 23–26
)
Striae composed of 3–5 small, rounded to slightly elongated areolae at the apices, only 1–2 rounded areolae per stria, extending past the terminal raphe fissures on the valve face (
Fig. 23
). A single row of rounded areolae present along entire valve mantle, interrupted at apices (
Fig. 26
). Isolated pore rounded, slightly elongated, not associated with a stria. Central area usually bordered by one, rarely two, series of small, rounded areolae. Raphe branches straight to slightly curved. Proximal raphe endings bent to the side opposite the isolated pore, terminating into weakly developed pores. Terminal raphe fissures bent to the same side as the proximal endings terminating on the valve face, not extending onto the mantle (
Fig. 24
).
Ecology and distribution
Luticola subcrozetensis
is a typical sub-Antarctic and Maritime Antarctic species. Originally described from Ile de la Possession (Crozet archipelago), the species was also reported from Livingston Island (
Zidarova
et al.
2016
), one of the major South
Shetland
Islands
, located in the southern Atlantic Ocean. The species was recently found in moss samples from Gough Island (Vinšová, unpubl. res.). It was present in samples from both Ile Saint-Paul and Ile Amsterdam.
The largest population was observed in a soil sample collected near the rockhopper penguin rookery of Ile Saint-Paul, at an altitude of
110 m
, hidden in cracks in the rocks that border the penguin rookery.