Valves are linear to linear-lanceolate with parallel to weakly convex margins and subrostrate rounded apices. The axial area is linear-lanceolate, approximately 1/4 of the valve width. Central area is rhombic, usually widened to a wide fascia, with a row of small puncta-like depressions on each side. Striae are radiate in the central valve, becoming strongly convergent toward the apices. Raphe is complex with undulate external slit. Proximal sections of the raphe are slightly expanded and inclined toward the primary valve side. Central pores are teardrop-shaped.
Pinnularia lailaensis has been reported from Spitsbergen and Alaska (Foged 1964, Krammer 2000). pH in type locality is 6.0.
Valves linear with almost parallel margins, drawn out and broadly rounded towards the apices, 65-70µ in length, 13-14µ in width. Raphe complex, the central pores slightly deflected to the same side. Axial area increases in width towards the central area, which reaches the margins of the valves like a transverse band.
There are two rows of isolated areoles in the central area placed in continuation of the inside pore openings of the striae. Mid-striae somewhat shortened, radiate, terminal striae slightly convergent, about 9-10 in 10µ.
Leppik, S., Potapova, M. (2024). Pinnularia lailaensis. In Diatoms of North America. Retrieved November 23, 2024, from https://diatoms.org/species/pinnularia-lailaensis
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Pinnularia lailaensis from all the stream reaches where it was present. Note that the relative abundance scale is the same on each plot. Explanation of each environmental variable and units are as follows:
ELEVATION = stream reach elevation (meters)
STRAHLER = distribution plot of the Strahler Stream Order
SLOPE = stream reach gradient (degrees)
W1_HALL = an index that is a measure of streamside (riparian) human activity that ranges from 0 - 10, with a value of 0 indicating of minimal disturbance to a value of 10 indicating severe disturbance.
PHSTVL = pH measured in a sealed syringe sample (pH units)
log_COND = log concentration of specific conductivity (µS/cm)
log_PTL = log concentration of total phosphorus (µg/L)
log_NO3 = log concentration of nitrate (µeq/L)
log_DOC = log concentration of dissolved organic carbon (mg/L)
log_SIO2 = log concentration of silicon (mg/L)
log_NA = log concentration of sodium (µeq/L)
log_HCO3 = log concentration of the bicarbonate ion (µeq/L)
EMBED = percent of the stream substrate that is embedded by sand and fine sediment
log_TURBIDITY = log of turbidity, a measure of cloudiness of water, in nephelometric turbidity units (NTU).
DISTOT = an index of total human disturbance in the watershed that ranges from 1 - 100, with a value of 0 indicating of minimal disturbance to a value of 100 indicating severe disturbance.