Chlorophyta - Ulvophyceae Flashcards
thallus? cell wall?
- order: Ulvales
- species: Ulva compressa
- thallus: hollow tube arranged in single layer
- inside: O2-bubbles produced by PS
- rhizoids near base for adhesion to substrate
diverse forms in Ulvaphyceae
class?
reproductive cycle?
- order: Ulvales
- species: Ulva rigida
- tubular bilayer laminar thallus (= composition of two layers of cells that are identical)
- has a haplodiplontic reproductive cycle
typical reproductive cycle of majority of Ulvales?
- haplodiplontic
what genera?
Ulva
- left: attached because rhizoids present
- but attachment not so firm: currents can make them pelagic
what order? what do the arrows show?
order: Bryopsiales
- Thallus with siphonal organization
- plurinucleated
- formed by a horizontal stolon from which rhizoids branch downwards and erect foliose blades upwards.
order? genus?
order: Bryopsidales
genus: Caluerpa
order? genus?
right: easy to identify: bubbles
order: Bryopsidales
genus: Caluerpa
order? genus?
order: Bryopsidales
genus: Caluerpa
order? genus?
order: Bryopsidales
genus: Caluerpa
Caulerpa paspaloides
order? genus?
order: Bryopsidales
genus: Caluerpa
important species in order Bryopsidales?
Caulerpa taxifolia
Caulerpa taxifolia - what about it?
- native in tropical and subtropical regions
- got bought and introduced to aquariums in Europe
- spreaded and covered large areas
- phenomena: gigantism
- introduced in Mediterranean
how was Caulerpa taxifolia introduced?
- probable spill from tank
- probably ballast water
- maybe from fisher nets/anchors
causes of proliferation? (=rapid increase)
- mild temp. in mediterranen
- no predators
- it has toxic compounds
- tropical species have usually developed natural immunity
- here: no immunity
- excessive growth
ideal environment for Caulerpa taxifolia
- surface - 50m depth
- 7-32°C
- can invade unstable/degraded environments
- prefers sands without settlement
consequences for Posidonia due to C. taxifolia?
- shading
- damage because there PS-activity is prevented through shade
Morphology of C. taxifolia
what is different for C. taxifolia in Mediterranean as compared to origin?
- in mediterranean affected by “gigantism”
- grows much more than normal
- normal length of blades: 10-12cm
- in mediterranean: 40cm
what is it? where from?
here: invasive
as compared to tropical
difference in blade lengths
toxicity of C. taxifolia
hazard:
- some cases of intoxication, attributed to Caulerpa toxins concentrated in the meat of some fish, so we can only talk about FOOD-TYPE INTOXICATION
- percentage of toxins usually higher in the Mediterranean than in tropical seas
- develops equally well in polluted and unpolluted waters
order? genus? thallus organization?
order: Bryopsidales
genus: Codium sp
- Thallus composed of a central body of siphonal organization filaments (all genera in Bryopsidales)
- compact mass of thin tubes that form a spongy thallus
- different forms, e.g. digitate, pulvinate or pillow, dicothomously branched
different examples of what genera? what is it considered the same thallus form?
order: Bryopsidales
genus: Codium sp
- left: sponge-similar attached to substrate
- it still is filamentous
- many filaments fused to form this form
order? genus?
order: Bryopsidales
genus: Codium sp
rhizpids present
order? genus?
order: Bryopsidales
genus: Halimeda
thalli form of Halimeda?
- It shows a thallus strongly encrusted with calcium carbonate to defend itself from herbivores
- flat calcified segments linked to each other with junctions
- junctions are not calcified and therefore they are flexible and move along the waves
order? genus? describe thallus
order: Bryopsidales
genus: Halimeda
- central axis
- linked encrusted segments linked to each other at end of axis
order? genus?
order: Bryopsidales
genus: Penicillus
thallus in Penicillus?
order: Bryopsidales
genus: Penicillus
- brush-formed
- dichotomouslybranched siphons
- peduncle with holdfast
- CaCO3 present –> grey green
order? genus?
order: Bryopsidales
genus: Udotea
order? genus?
order: Bryopsidales
genus: Udotea
characteristics of Udotea?
- rhizoids for attachment and short peduncle
- blade-similar structure due to fusion of different filaments
class? order?
class: Ulvophyceae
order: Ulotrichales
- no branches
- uniseriate
- filaments of uninuclear cells
- filaments joint by plasmodesmata
order?
Ulotrichales
order?
class: Ulvophyceae
order: Dasyclades
genus: Cymopolia barbata
oder? genus?
class: Ulvophyceae
order: Dasyclades
genus: Cymopolia barbata
oder? genus?
class: Ulvophyceae
order: Dasyclades
genus: Cymopolia barbata
Characteristics Cymopolia barbata
class: Ulvophyceae
order: Dasyclades
- shallow waters
- reaches length of 20cm
- tufts slightly calcified at the end of branches
oder? genus?
class: Ulvophyceae
order: Dasyclades
genus: Cymopolia sp.
oder? genus?
class: Ulvophyceae
order: Dasyclades
genus: Acetabularia
what about Ulva australis?
class: Ulvaphyceae
order: Ulvales
genus: Ulva
- produces allopathic substrate
Ulva rigida vs Ulva australis
- Ulva rigida here invasive
- can cause damage
problem also in China, due to high reproductive rate
what is that?
- ‘‘green tides’’
- Ulva australis
- usually in high nutritious environment
