Valves are elliptic-lanceolate to lanceolate with short protracted rostrate apices. The axial area is very narrow. The central area is only slightly wider than the axial area and elliptic in shape. The raphe is filiform with straight, weakly expanded proximal ends and distal ends that are hooked in the same direction. Striae are parallel to weakly radiate at the valve center, becoming convergent towards the apices. Areolae are extremely fine and not easily resolved in LM.
Craticula buderi is widely distributed in a variety of habitats throughout the Northwest United States, where it prefers alkaline waters with moderate levels of dissolved solids. There are 80 confirmed records of this taxon in the Montana Diatom Collection. North Widgeon Slough in Sheridan County, Montana, produced the specimens imaged here. On the sampling date, North Widgeon Slough had a pH of 8.70 and a specific conductance of 12,800 µS/cm.
Valvae late ellipticae apicibus late rotundatis, saepissime lineares vel lineari-lanceolatae apicibus obtuse cuneatis vel rostratis, 7 bis 20 µ longae, 4,5 bis 6,5 µ latae. Rhaphe directa, filiformis, fissuris terminalibus in eadem directione curvatis. Area axialis angustissima, area centralis nulla vel minima. Striae transpicales ad lineam mediam perpendiculares, 17 bis 20 in 10 µ, striae longitudinales delicatssimae. Fig. 11 bis 15.
Specimens of the morphological range shown here were originally posted on the Diatoms of the US site (J.P. Kociolek, contributor) as Craticula halophila. Further work showed that the specimens here are aligned with the type of Craticula buderi. The name of this page was changed from C. halophila to C. buderi. A new page for C. halophila was opened. - S. Spaulding
Bahls, L., Kociolek, P. (2012). Craticula buderi. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/craticula_buderi
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Craticula buderi 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.