morphological characteristics
is often single cells, and individual types of cells are located in a single or branched colloidal tube. The length of the cells, the shell is straight or "S" shape, the linear or elliptical shape, the edges of both sides are maintained or not wound, and the two ends are tit, near the shaped or earlier. The keel protrudes of the upper and lower shells, cross each other, the shell surface is rigid, or 1 column. Containing viewing of fry. Most types of pigments are 2, strip-shaped, located on one side of the belt, and a few categories of 4 to 6 pieces. Two parent cells were respectively formed by two parent cells, and 2 pairs of assigles were bonded to each other.
Distribution
This belongs have a total of 350 species, and more than 76 of China.
Both fresh water, semi-salty water and sea water, also have fossil species.
Represents species
(1) fine decorative algae
Latin name: Nitzschia Denticula
morphological characteristics: Shell surface narrow picked needle shape, terminal pointed, sometimes slightly bezel, long 10 ~ 100 microns, width 3 to 8 microns; keel is very narrow, long bone points are prolonged, 5 to 8 internal 10 micron equipment; 14 to 20 horizontal lines consisting of obvious distal lines 10 microns. With surface rectangles, parallel or slightly convex on both sides.
Freshwater prehealth type.
(2) Chi Snooked algae
Latin Name: Nitzschia Stagnorum
morphological characteristics:
Shell surface line, slightly concave on both sides, gradually narrow, end wedge, length 30 ~ 60 microns, wide 5 ~ 10 microns; keel is very narrow, long bone points, slightly round, 10 micron inside 7 ~ 9; 26 horizontal lines 10 micron equipment. Band line shape, parallel to both sides or slightly across or slightly protruding, and the end is wide.
Freshwater preparation, especially in a small water storage, the glass wall of the greenhouse.
(3) Linear diamond
Latin name: Nitzschia linearis < / B>
morphological characteristics:
Shell rod shape, parallel on both sides, the middle edge of the end of the roll protrusions, both ends The narrow, the end protrudes, 70 ~ 180 microns long, 5 ~ 6 microns wide; 8 to 13 orthopedic noodles 10 micron; 28 to 30 pieces of horizontal lines 10 micron equipment.
Freshwater premature type, often in the spring water.
(4) Riring algae
Latin Name: Nitzschia Frustulum
morphological characteristics:
Shell surface line to linear lanceolate, long or shorter wedge, gradually narrow, end pointed, length 13 ~ 70 microns, 3 to 5 microns in width; 9 to 13 ingrage 10 microns; horizontal lines are thick, 10 micron equipment 20 ~ 24.
Freshwater and semi-salty water preparation species.