Lab Activity 9.2
Biota 1: Seaweeds Found on Beachrock Surfaces

  Directions

Study the instructional material below. Be sure to click on each of the photographs for an enlarged view in a separate window. The larger version is necessary to complete the assignment. It opens in a separate window which can be resized by grabbing the bottom right corner and dragging it. It can also be moved by grabbing the top heading bar and dragging it. Be sure to close the extra window by using the X in IBM, or the close box in MAC when you are finished using them.

  Introduction


In this lab activity you will study the seaweeds of beachrock surfaces.

Top  Instruction

Use the information below to fill out the checklist of the biota of beachrock microhabitats.

Be sure to write about what you are learning in the lab section of your notebook. You will be expected to answer questions about the lab activity during the lab self test and lab quiz. It helps to have your text and coloring books open beside you for support.

 
Supporting Information
Refer to the Assigned Readings Below:
Marine Biology Textbook none
Marine Biology Coloring Book none
 

This picture gallery summarizes the seaweeds found on top of beachrock at Playa Estacion, Puerto Penasco, Sonora, Mexico.

It should be used to complete lab activity 9.2.

 

Valoniopsis pachynema
"Moss-like algae"
Division  Chlorophyta
Class  Chlorophyceae
Order   
Family   Valoniaceae
Morphology Forming stiff, spongy mats of tangled, prostrate filaments. Green color. To one and a half inches long.
Habitat On rocks in the intertidal
Distribution Throughout the tropics including the Gulf of California
Other

 

Colpomenia tuberculata

"Bumpy membrane algae"
Division  Phaeophyta
Class  Phaeophyceae
Order   Scytosiphonales
Family   Scytosiphonaceae

Morphology Bubble-like, thick, crispy frond with a bumpy surface. Attached broadly to the rock surface. Golden brown color. Two to four inches in diameter.
Habitat On intertidal rocks
Distribution Southern California to Ecuador and throughout the Gulf of California
Other

 

Colpomenia sinuosa
"Sinuous membrane algae"
Division  Phaeophyta
Class  Phaeophyceae
Order   Scytosiphonales
Family   Scytosiphonaceae
Morphology Bubble-like, thin, frond with a smooth surface. Attached broadly to the rock surface. Greenish brown color. One to two inches in diameter.
Habitat On intertidal rocks
Distribution Southern California to Chile, throughout the Gulf of California, and in the north Atlantic
Other

 

Colpomenia phaeodactyla

"Finger-like membrane algae"
Division  Phaeophyta
Class  Phaeophyceae
Order   Scytosiphonales
Family   Scytosiphonaceae
Morphology Clusters of long, finger-like, hollow, fronds with thin walls and smooth surfaces. Attached narrowly to the rock surface. Golden brown color. One to two inches long.
Habitat On intertidal rocks
Distribution Widely distributed in cool Pacific waters
Other

 

Sargassum johnstoni

"Johnston's grape weed"
Division  Phaeophyta
Class  Phaeophyceae
Order   Fucales
Family   Sargassaceae
Morphology Densely crowded, short, narrow, leaf-like blades. Small, elliptical, gas filled vesicles. Basal holdfast is short. Brown color. To a foot or more in length.
Habitat On shallow subtidal and intertidal rocks and in tidepools
Distribution Gulf of California
Other

 

Sargassum sinicola

"Leafy grape weed"
Division  Phaeophyta
Class  Phaeophyceae
Order   Fucales
Family   Sargassaceae

Morphology Long, narrow, leaf-like blades with toothed edges. Smooth stem-like stipes and spherical, gas filled vesicles. Basal holdfast is short and branched. Brown color. To a foot or more in length.
Habitat On shallow subtidal and low intertidal rocks and in tidepools
Distribution Gulf of California
Other

 

Laurencia paniculata

"Turf Laurencie's weed"
Division  Rhodophyta
Class  Florideophyceae
Order   Ceramiales
Family   Rhodomelaceae
Morphology Crisp, greenish-brown, with many erect branches covered with stubby branchlets. Radial branching pattern (Christmas-tree like). One to two inches tall.
Habitat Part of a multispecies, compact, spongy turf carpeting intertidal beachrock
Distribution Gulf of California
Other