Rocky Shore Flashcards
1
Q
A
% Ulva intestinalis (gut weed)
- Simple thalli (fronds) arise from a small discoid base.
- Thalli light to dark grass-green in colour.
- Thallus completely tubular and elongate, increasing in width from base to mid thallus.
- Mature specimens, are ‘crisped’ and irregularly inflated
- Thalli typically unbranched
2
Q
A
% Ulva lactuca (sea lettuce)
- Up to 30 cm across.
- Frond broad and crumpled, that is tough, translucent and membranous.
- Disc like holdfast.
- Green to dark green in colour.
3
Q
A
% Ascophyllum nodosum (knotted wrack)
- Frond narrow without midrib.
- Large swollen egg shaped air bladders at intervals along middle of the frond.
- Reproductive bodies rounded on short stalks.
- Dichotomously branched.
4
Q
A
(%) Polysiphonia lanosa (wrack siphon weed)
- Reddish brown filamentous alga.
- An epiphyte of Ascophyllum nodosum, on which they look like ‘pom poms’.
5
Q
A
- Fronds are flat and straplike with a well developed mid-rib.
- Fronds edged with sharp, forward-pointing serrations.
- The frond bears no air bladders.
- The frond surface has numerous pin-pricks with clusters of tiny white hairs.
- Receptacles form slightly thickened patches about 4 cm long.
6
Q
A
% Fucus spiralis (spiral wrack)
- Frond with smooth margin.
- Prominent midrib.
- Without air bladders.
- Frond often twisted.
- Round reproductive bodies at ends of branches, which are almost round in outline.
7
Q
A
% Fucus vesiculosus (bladder wrack)
- Frond with prominent midrib, smooth frond margin and almost spherical air bladders.
- Air bladders usually paired but may be absent in very small plants.
- Frond dichotomously branched.
- A bladderless form occurs on more wave exposed shores
8
Q
A
% Laminaria digitata (oarweed)
- Frond is broad, leathery and digitate.
- Lacks a midrib.
- Stipe is flexible and smooth, oval in cross section and free of epiphytes except maybe Palmaria palmata in older kelps.
- Holdfast of freely branched haptera which spread out to form a shallow dome.
- May be confused with young Laminaria hyperborea plants. However, the stipe of Laminaria hyperborea is circular in cross section and stiff.
9
Q
A
% Saccharina latissimi (sugar kelp)
- A long undivided frond with wrinkled surface and wavy margins, rising from a smooth flexible stipe.
- Without midrib.
- Small branching holdfast.
- Yellowish-brown in colour.
- Up to 4 m long.
10
Q
A
% Corallina officinalis – tufted (coral weed)
- Erect stiff, articulated fronds, coarse to the touch.
- Purple, reddish, pink or yellowish in colour.
- Branching opposite (pinnate).
- Disc shaped holdfast.
11
Q
A
% Chondrus crispus - Carrageen
- Un-branched stipe gradually expanding into fan-like blade.
- Fronds repeatedly dichotomous (up to 5 times) with rounded axils, usually expanding but occasionally tapering towards rounded apices.
- Female fruiting bodies (carposporangia) occur terminally in cystocarps that protrude strongly as concave-convex swellings 2 mm in diameter.
- Form highly variable depending on environment.
12
Q
A
% Mastocarpus stellatus (false irish moss)
- Up to 17 cm in length.
- Channelled fronds with thickened edge widen from a narrow stipe.
- Disc like holdfast.
- Darkish reddish-brown to purple in colour
13
Q
A
% Osmundea pinnatifida (pepper dulse)
- A small red seaweed up to 8 cm in length.
- Tough with flattened fronds.
- Alternate branching, branches become shorter towards the top and broadly rounded.
- Highly variable in size and colouration depending upon its location on the shore.
- Colour ranges from yellow-green to reddish brown.
14
Q
A
% Rhodothamniella floridula (sand binder)
- Brownish red in colour
- The base forms a spongy, carpet like covering on rocks
- Fine branched filaments up to 3 cm in length
- Branches may be upright or creeping
15
Q
A
% Electra Pilosa (thorny sea mat)
- About half the front of the zooid calcified and perforated by large pores.
- Autozooids oval-oblong, about 0.5 mm long
- Colony has a more angular shape than Membranipora membranacea (sea mat)