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Fossilladyhttps://fossillady.wordpress.comThis is where I combine my photography and writing to share my fascination with fossils, beach stones, seashells and corals.

From Tree to Stone

November 26, 2017 by Fossillady

Triassic Period, Araucarioxylon, arizonicum (Petrified Forest National Park) Drawing Rendition

The drawing above is a rendition I drew with colored pencils of Araucarioxylon, arizonicum, an extinct conifer tree identified from the petrified wood from the infamous Petrified Forest National Park located in the U.S. State of Arizona. Originally, it was thought to be a distant relative of the Araucaria tree or the Norfolk Pine, which you often see for sale during the Christmas season as potted plants. Without detailed microscopic examination of the wood, its link to present day trees is only speculation at this point. Modern scientific discoveries indicates there were more species than originally thought lying on the dry Arizona plateau.

Triassic Period Araucarioxylon, arizonicum petrified wood fossil from Arizona Petrified Wood National Park

Triassic Beginnings

During the Triassic Period, around 225 million years ago, the present day continents were melded together as one supercontinent called Pangea. By the end of the era, around 200 million years ago, widespread volcanic activity began to break the continents apart. The first dinosaurs and mammals had evolved and there had been a boom in cycads (palm like trees), giant tree ferns and conifers . . . enter the Araucarioxylon of Arizona, a type of conifer or pine. It differs from modern day conifers with its sporadic branch growth pattern around the trunk rather than growing in level whorls. It grew up to 200 feet (60 meters) tall with a 9 foot (2.7 m) diameter. Compare that to the tallest current living conifers, the Sequoias, that grow up to 188 feet (57 meters). To help put that into perspective, maple trees reach up to about 50 feet (15 m) and oak trees top out at about 80 feet (24m) tall.

Triassic Landscape

From Tree To Stone

The high and dry tableland in northern Arizona where the National Petrified Forest Park rests, was a vast flood plain during the Triassic Period overflowing with streams and widespread ponds. Prehistoric, extinct plants and trees concentrated along the spilling bodies of water. Dying or blown over trees were washed down the streams into the flood plains where they gathered and decayed. If they were buried under mud, silt or volcanic ash deep enough to cut off oxygen, it slowed the decaying process. Silica laden groundwater gradually seeped through the logs replacing the original wood tissue with silica deposits. As the process continued over the ages, the wood was replaced, atom by atom, with silica crystallized into mineral rich quartz, ultimately turning the wood into a rather attractive stone.

Triassic Petrified Wood Fossil Araucarioxylon, arizonicum from Petrified Forest National Park

Petrified Wood Colors

Various colors, often striking, are produced depending on the mineral contents in the stone:

PINK or RED – Hematite present – a form of oxidized iron – This interesting process is well explained from ScienceView.com. Iron dissolves in ground water when no oxygen is present. The ground water becomes re-oxygenated as it moves though the tree trunks causing oxygen to bond with the iron. The iron then precipitates to produce a solid form of iron called hematite. This hematite is incorporated into the log’s cell walls. The same process occurs when iron stains porcelain sinks. The soluble iron in ground water becomes oxidized into a solid form when it comes in contact with air, causing a reddish stain.

YELLOW BROWN or ORANGE – Goethite present- a weathered hydrated iron oxide that becomes crystallized

GREEN – Pure native iron present

WHITE – Pure Silica present – Silicon, Si, and oxygen, O, are the two most abundant elements in the earth’s crust which together form silica dioxide quartz

BLACK – Carbon or Pyrite or Iron Sulfide (the most wide spread sulfide) present – The wood was affected as hydrogen sulfide from decaying organic matter interacted with iron forming pyrite.

PURPLE or BLUE – Manganese present – This is a secondary material formed when water leaches manganese from igneous rock and re-deposits it as a concentration of manganese dioxide.

TAN – Silica Dioxide present – naturally found in water, plants, animals, and the earth

Uplift

How did the petrified wood of Arizona become uncovered? First, millions of years ago, the area sank to the point which completely flooded everything with freshwater sediments. It continued to sink deeper becoming completely buried. Millions of years later, the area was lifted far above sea level from westerly continental plate pressure. The uplift created stresses that cracked the giant logs. Over time, wind and water have worn away the layers of hardened sediments, exposing the fossilized wood.

Lake Michigan Petrified Driftwood

Petrified Driftwood Lake Michigan Beach

While the Petrified Forest of Arizona has the highest concentration of petrified wood in the world, it can be found in every US state and other countries around the world. I found this sample of petrified driftwood on a Southwest Michigan beach off Lake Michigan called Oval Beach. It’s predominantly gray with a slight bluish green cast and has a few streaks of rust. In certain light, it casts a very bright sheen or luster. It’s difficult to capture the sheen in a photograph, but you can get a better idea from its flip side in the photo below.

Petrified Driftwood Lake Michigan Beach

After researching the possible mineral contents of my sample, according to its dense property, color and luster, my best guess tells me that it’s hematite specularite. I have collected driftwood on the beach very often, but never before a piece that was petrified!

See a sample of petrified wood of extinct scale trees, from one of my previous posts.

Timetable of Clams

April 2, 2017 by Fossillady

Timetable of Bivalve (Clams) Rendering Drawing

What is a clam and how do they live? “Clam” can be a term that covers all bivalves (pelecypods). Bivalves such as oysters and mussels attach themselves to hard objects, and scallops can free swim by flapping their valves together. Some clams bury themselves in sand and breathe by extending a tube to the water’s surface. Those varieties usually possess a stronger foot that looks like a tongue which the clam uses for digging and pushing itself along.

Clams feed by filtering plankton with their adapted gills, although the digging varieties use a siphoning tube and more primitive species used special tentacles. Bivalves lack a head or brain and usually have no eyes, although scallops are a notable exception. All bivalves possess a mouth, heart, kidneys, and anus, as well as a circulatory system. Clams haven’t changed much through the timetables surviving multiple earth changes and mass extinctions!

Clam Fossils Identification Colorcoded Matched with Drawing Clam Fossils – Oldest to Recent

CTENODONTA FOSSIL CLAM Source

Orange Rendering: Ctendonta levata possesses a well developed beak, a smooth surface with fine concentric growth lines and teeth along the hinge plate. Lived from Ordovician to Silurian (505 to 408 million-years-ago) very old.

MODIOLOPSIS FOSSIL CLAM

Deep Pinkish Rendering: Modiolopsis genus possess asymmetrical thin valves crossed by an oblique depression and strong beak. Possible fossil sample below is a mold of the inner shell which has been extremely smoothed by the movement of sand and waves. Lived from Ordovician to Silurian (505 to 408 million-years-ago)

BYSSONYCHIA FOSSIL CLAM Source

Blue/Green Rendering: Byssonychia genus has a sharp steeply inclined beak near the end of the hinge; usually has strong radial ribs. Mostly Upper Ordovician around 400 million-years-ago.

Timetable of Bivalve (Clams) Rendering Drawing

GONIOPHORA FOSSIL CLAM Source

Brown Rendering: Goniophora levata has a lopsided shell with a prominent beak and ridge extending to the rear margin. Silurian to Devonian (438 to 360 million-yeas-ago)

PTERIA FOSSIL CLAM Source

Goldish and Brown Rendering: Pteria colymbus genus has thin inequilaterally shaped valves with a long straight hinge merging into large unequal wings. Jurassic to recent (245 million-yeas-ago to recent)

GLYCIMERIS FOSSIL CLAM Source

Yellow Rendering: Glycimeris genus has symmetrical circular outline with pointed beak. Cretaceous to Recent (114 mya to recent)

PECTEN FOSSIL SCALLOP CLAM Source

Deep Blue/Purplish Colored Rendering: Pecten is a genus of many well known bivalves otherwise known as scallops. Valves have strong radial ribs and are almost symmetrical except for unequal wings. Mississippian to Recent (360 million-yeas-ago to recent)

Bivalves feed the world. Bivalve oysters, scallops and clams are near the bottom of the food chain which many marine and freshwater species depend on for a food source. But don’t forget about land creatures such as otters, for one, and we humans who especially enjoy a treat of clam chowder, fresh shrimp or oysters on the half shell. The animal secreted calcium carbonate from the ocean to creat a protective shell, they can be beautiful and are used to adorn our homes in creative ways. Scan_Pic0009

Coral Sponge

March 28, 2014 by Fossillady

Florida Sponge Fossil Skeleton

The title, Coral Sponge, gives reference to the beautiful coral color of this sample and because I’m 99% certain it’s a sponge and not a coral fossil. The main reason is for the lack of vertical septa walls inside the cups, or in the case of sponges, inside the pores.

Coral cups showing septa walls lacking in sponges

There are some 5,000 to 10,00 known species of sponges and identification usually depends on the patterns and shapes of their spicules (tiny rods used for defense), usually only visible through a microscope in order to distinguish.

In lieu of this, I can only wager a guess as to its exact identity. It’s a rather attractive piece from my mother-in-law’s collection she gathered in the 70’s and 80’s off Florida beaches. So, I’m guessing it’s a type of calcareous type which forms a hard calcium carbonate skeleton; and I would also predict that it’s a tube type as well.

Below, I found an image of a tube type of sponge from a Florida reef. It looks fairly close in comparison.

Brown Cluster Tube Sponge Source

INTERESTING SPONGE FACTS

Sponges are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them.
Sponges do not have a nervous system, nor a digestive or circulatory systems; instead, they depend on a waterflow system to perform all the necessary functions.
For defense, sponges shed rod-like spicules forming a dense carpet several meters deep that keep away echinoderms (i.e. starfish) which prey on them. They also may produce toxins that prevent other prey from growing on or near them.
Their bodies have two outer layers, separated by a non-living gel layer which contains the tiny rod-like spicules.
Sponges are sessile (attached to a substrate or hard surface).
Most sponges live in quiet, clear waters environments to avoid sediment stirred up by waves or currents which would block their pores making it difficult for them to feed and breathe.
Sponges improve water quality as effective biological filterers, extracting microscopic food and bacteria from the current.
Sponges evolved over 500 million years ago.
Sponges form different shapes, including tubes, fans, cups, cones, blobs, barrels, and crusts.

Sponge Classification

Kingdom: Animalia (animals)

Phylum: Porifera (Having Pores)

Four Classes

Demosponges – Largest class; Inner structure reinforced with collagen fibers and spine-like spicules made of silica minerals; Usually barrel shaped; Can live in a wide variety of habitats; Some are bath sponges

Hexactinellida – Glass Sponges; Spiny spicules made of silica minerals forming inner scaffolding structure with gelatin substance weaved in between framework; likes Polar Regions

Calcareous – Outer exoskeleton and inner spicules made of calcium carbonate. Restricted to shallow marine waters where production of calcium carbonate is easiest to obtain.

Scleropongiae (Coralline or Tropical Reef Sponges) soft body that covers a hard, often massive skeleton made of calcium carbonate, either aragonite or calcite. The layered skeletons look similar to reef corals, therefore are also called coralline sponges.

Maze Coral and Rose Coral Comparison

March 25, 2014 by Fossillady

Maze Coral

Maze Coral (Meandrina, meandrites) Living Sample
Source

Judging from the title of this article, you may have gathered their can be some confusion when identifying coral fossils and you would be right. All corals are not single organisms, but rather are a colony of individuals we know as polyps (the jelly-like part). The polyps band together and slowly build a calcium carbonate skeleton. Herein lies the physical diversity of corals as each species builds a slightly different style of skeleton.

I was confused by several coral species that I now feel confident about their identities after some head scratching and investigating. Maze Coral and Rose Coral fossil skeletons look very similar at first glance; descriptions below solves the puzzle.

Both species are commonly found in the Bahamas, Caribbean and Florida shores.

Maze Coral Fossil (Meandrina, meandrites) Fossil Skeleton

While researching, I realized that maze corals are sometimes lumped together with brain corals, or are even called maze-brain corals. The most distinguishing features from rose corals is that the maze-brain coral grow larger and display deeper ridges with well defined irregular plates less rounded than the rose coral. Also, there is an indentation running along the crest of the walls where the adjoining plates meet. Maze coral colonies form both flat heads and hemispherical (half-sphere) dome plates; colors tend to be brownish or greyish when live.

Maze Coral Habitat: Found in a wide range of habitats across the Caribbean, Gulf of Mexico, Bermuda, the Bahamas and Florida occurring at any depth less than 80 meters (260 feet) in reef-environments.

Maze Coral Classification
Kingdom: Animalia
Phylum: Cnidaria (Animal with stinging cells)
Class: Anthozoa (Flower like animals)
Subclass: Hexacorallia (polygonal corals having parts in multiples of 6)
Order: Scleractinia (Stony Skeleton)
Family: Meandrininidae (Meandering Colony Corals)
Genus: Meandrina (forms massive hemispherical heads or have large flat plates and can grow to one meter (3 feet) across)
Species: M. meandrites

Rose Coral

Rose Coral (Manicina, areolata) Skeleton

Rose Coral “Manicina, areolata” is a small stony coral often forming elliptical or oval colony heads with wide, winding valleys and rounded fleshy furrows; also, meandering valleys grow atop of smaller, shorter ridges. Colonies are often unattached to the seabed, living on sandy or seagrass bottoms.

Rose Coral (Manicina, areolata) Living Sample
Source

Interesting Behavior

Rose corals are one of only a few corals that can be actively mobile. If a small colony of rose corals gets turned upside down, it proceeds to gorge its stomach with water in order to bloat, and then it jets the water out from one side at a time. This causes a back and forth rocking motion until the center of gravity shifts, allowing it to rapidly flip upright. The entire process takes a few hours until it finally flips over in an instant.

Rose Coral (Manicina, areolata) Skeleton

Habitat: Rose coral “Manicina, aerolata” is very abundant off the Floridian shores as well as the Bahamas and Caribbean. It prefers shallow, productive, near shore habitats characterized by abundant sediments such as seagrass meadows, or along the fringes of mangrove forests. Larger colonies are more likely to die by smothering in the sediments placing a limit on the size any given colony can grow.

Colors: Yellowish-brown, tan or dark brown, often with the valleys and walls being contrasting colors. Like most corals, the polyps are only extended at night and are often green.

Rose Coral (Manicina, aerolata) Living Sample
Source

ROSE CORAL CLASSIFICATION

Kingdom: Animalia
Phylum: Cnidaria (Animals with stinging cells)
Class: Anthozoa (Flower Animal)
Order: Scleractinia (Stony Skeleton)
Family: Faviidae (generally spherical shape and grooved surface which resembles a brain)
Genus: Manicina
Species: M. areolata

Note: The genus, Manicina, includes over 10 species, but Manicina, areolata is the only species that survives today. The heyday for Manicina was during the Miocene and Pliocene epochs between (24 million to 1.6 million years ago). About one million years ago, approximately half the species of reef corals living in the Caribbean became extinct.

Both Maze Coral and Rose Coral are considered threatened species, though their specific status and risk factors differ.

For more interesting facts, photos and identification of Florida, Gulf and Atlantic Coast Corals to “Categories” sidebar under “Corals, Forida, Atlantic and Gulf Coasts”

Low Relief Lettuce Coral

March 23, 2014 by Fossillady

Low Relief Lettuce Coral Skeleton (Agaricia, humilis)

Low relief lettuce coral is fairly common with a widespread distribution in the open seas of the Caribbean, Bahamas and Florida, often scattered among other corals within inner bays and sometimes within mangrove roots. It can thrive from shallow sea levels to the lower depth limits of the reef, approximately 60 meters (200 feet) deep. It displays a number of growth forms, such as appearing saucer-like on cliff sides or small half-moon shaped in shallow depths. In depths deeper than 10 meters (3 feet), the coral forms broad vertical scales with corallites on one side only.

Low Relief Lettuce Coral (Agaricia, humilis) Living Sample
Source

CLASSIFICATION:

Kingdom: Animalia
Phylum: Cnidardia (C is silent) Marine group with stinging cells
Class: Anthozoa – Flower Animal
Order: Scleratinia – Reef building stony corals
Family: Agariciidae – includes cactus corals, elephant skin corals, plate corals and lettuce corals. Members of the family include symbiotic algae called Zooxanthellae in their tissues which help provide their energy
Genus: Agaricia – lettuce corals
Species: humilis – low relief

Winkie, Joe, Johnny and Joey, 1950’s

As I have mentioned in other coral posts, my mother in law, Winifred (Winkie) loved collecting coral during Florida vacations in the 60’s and 70’s. My late husband, Joseph III, came from a hard working family in the 50’s living in Detroit. His dad, Joseph II, was a designer for Chrysler Corporation and designed an amphibious vehicle used in WWII.

I feel honored to have samples from her coral collection and am excited to share them with you. She would have been thrilled by this.

For more interesting facts, photos and identification of Florida and Atlantic Coast Corals scroll to sidebar “Categories” under “Corals Florida, Atlantic and Gulf Coasts”.

Cactus Coral Pavona

March 21, 2014 by Fossillady

Coral Skeleton Shows Closely Spaced Polyps of the “Cactus Coral (Pavona)“

After much digging around I finally identified this amazing specimen as a Cactus Coral from the genus of Pavona. The small prickly pattern of polyp corallites was the best defining feature, as well as the folding plates that loosely resemble a cactus.

Cactus Coral (Pavona) Living Sample
Source

The Pavona, Cactus Coral is a small-polyp, stony coral which has been called, Cactus, Potato Chip, or Lettuce Coral. A single species may vary in form according to the currents, wave action, lighting conditions and depth of its location. They can also vary in color from shades of light and dark brown to green with cream or white margins. Some have a fluorescent glow that can be seen beneath the polyps, giving these corals an interesting look. They are known to make a popular addition to the home aquarium.

Cactus Coral (Pavona) Living Sample
Source

CACTUS CORAL CLASSIFICATION

Kingdom: Animalia
Phylum: Cnidardia (A group containing over 10,000 species of animals found exclusively in aquatic and mostly marine environments. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey by shooting off a threadlike, often toxic, tubule from inside the cnidocyst.)
Class: Anthozoa (Flower Animal)
Order: Scleratinia (Stony corals which are marine corals that generate a hard skeleton. They first appeared in the Middle Triassic and descended from the tabulate and rugose corals that barely survived the end of the Permian. Much of the framework of today’s coral reefs is formed by scleractinians. Stony coral numbers are expected to decline due to the effects of global warning and increased acidity due to pollution.)
Family: Agariciidae (Reef building stony corals including cactus corals, elephant skin corals, plate corals and lettuce corals.)
Genus: Pavona (Coral colonies of this type have vertical, irregular, two-sided fronds.)
Species: Possibly minuta or duerdeni

For more interesting facts, photos and identification of Florida and Atlantic Coast Corals Scroll Here if you’re not already viewing this post under “Coral Florida” in the Categories list.

Boulder Brain Coral and Symmetrical Brain Coral Compared

March 19, 2014 by Fossillady

I have two species of coral from my collection that have earned the common name, Brain Corals, due to their convoluted surfaces, loosely resembling the physical brain and general spherical formations. Both species are slow growing, colony forms which may reach colossal sizes to a few meters in length and live for hundreds of years. The oldest know brain coral is 900 years old. Both species below grow in shallow parts of the Caribbean Sea, the Bahamas, Bermuda, Texas and Florida.

Boulder Brain Coral (Colpophyllia, natans) Skeleton

Boulder Brain Coral (Colpophyllia, natans) is a very large brain coral diplaying domed, hemispherical colonies that may exceed one meter (3 feet) across, but smaller colonies may be flat discs depending on location.

Large Brain Coral Boulder Skeleton – 14 iches across (35 cm)

Boulder Brain Coral polyp valleys on the surface may stretch the entire width, or be subdivided into shorter series. The valleys and walls may be two centimeters broad distinguishing it from my Symmetrical Brain Coral (shown below) which display narrower valleys and walls.The walls of the Boulder Brain Coral commonly have fine grooves running along the raised walls. The Boulder Brain Coral also has a sharp break between the wall and the valley floor. The living Boulder Brain Coral colors vary with ridges being various shades of brown, and the valleys are varied colors from whitish, green, or tan.

Boulder Brain Coral (Colpophyllia, natans) Living Sample Source

Symmetrical Brain Coral

Symmetrical Brain Coral (Diploria, strigosa) Skeleton

Symmetrical Brain Coral (Diploria, strigosa) forms flat plates or massive hemispherical domes up to 2 meters, (6 feet) in diameters. Sometimes, they will show a very narrow groove along the tops of the walls, which have sloping or rounded sides. Valleys may run straight for considerable distances or be highly irregular in direction. Living samples range in color from purplish brown to tan, grey or green, often with the groove floors being a contrasting paler color.

Diploria, strigosa is the most widespread of all the Diploria species, being more resistant to threats with the ability to thrive in muddy stretches of seabed where many other corals are not able to flourish needing clearer waters.

Symmetrical Brain Coral (Diploria, strigosa) Living Sample

Brain Coral Habitat

NOTE ABOUT SCLERACTINIA: The order “Scleractinia” includes all living corals today developing a stony, light porous skeleton. Scleractinians were fairly rare in North America until the Cretaceous, about 100 million years ago, when they first built reefs in Texas and Mexico. It wasn’t until the Pleistocene Period, about 2.6 million years ago, that reefs flourished widely where they do today.

Brain Coral Open Polyps At Night

Night Time Activity : Coral polyps, the living breathing jelly-like part of the animal, are found in single file in the valleys of this brain coral’s convoluted ridges. They are normally contracted during daylight expanding at night to catch micro-bits of food drifting by.

BRAIN CORAL CLASSIFICATION

Kingdom – Animalia
Phylum – Cnidaria (means stinging cells)
Class – Anthozoa (means flower animal)
Order – Scleratinia (stony skeleton)
Family – Faviidae (spherical group with grooved surfaces)
Genus – Colpophyllia (large-grooved) / Diploria (grooved)
Species – strigosa (thin, narrow, well-defined ridges) / natans

For more interesting facts, photos and identification of Florida, Gulf and Atlantic Coast Corals scroll to “Categories” sidebar under “Corals Florida, Atlantic and Gulf Coasts.

Pillar Coral

March 18, 2014 by Fossillady

Pillar Coral (Dendrogyra, cylindricus) Skeleton

Pillar Coral is one of the most spectacular stony corals found in the Western Atlantic Ocean, Southern Florida and Caribbean Seas. It derives its name for obvious reasons from its sizeable finger-like branches. They can reach a height of nearly 3 meters (9 feet). Dendrogyra cylindrus) inhabits shallow, warm, clear waters from 3 to 80 feet depths (1 to 25 meters), typically on reef, rocky or sandy substrates. They are commonly found on flat to gently sloping areas in well-circulated, nutrient-poor areas.

Pillar Coral colonies were once more abundant along the Florida reefs, but commercial collections and coral bleaching has greatly reduced the occurrence of Pillar Corals placing them on the endangered list.

Pillar Coral (Dendrogyra, cylindricus) Living Sample
Source

Pillar Corals extend their polyp tentacles during the daytime, unlike most other stony corals. The tentacles gently sway with the currents and if one of the polyps is touched by something foreign, it swiftly contracts causing a wave of shriveling polyps sweep over the entire colony in a period of a few seconds.

Check out this exceptional photo of Pillar Coral

CLASSIFICATION OF PILLAR CORAL

Kingdom: Animalia
Phylum: Cnidardia (Large marine group characterized with stinging cells, tentacles and no skeletons or organs)
Class: Anthozoa (Flower Animal)
Order: Scleratinia (Stony Coral)
Suborder: Faviidae (General Spherical Shape)
Family: Meandrinidae (Meandering valleys between corallites)
Genus: Dendrogyra (Tall pillar like growth form)
Species: Cylindricus

What’s being done to bring back threats to coral reefs? Coral farming; see video to find out about this effort to restore the reef along Florida Keys.

I feel privileged to have inherited this sample as part of a collection from my beautiful mother-in-law, Winkie.

1983 Ft. Lauderdale Florida
Winkie and Father-in-Law, Joe

For more interesting facts, photos and identification of Florida and Atlantic Coast Corals scoll to the “Categories” sidebar to “Corals Florida, Atlantic and Gulf Coasts”.

Finger Corals

March 17, 2014 by Fossillady

Finger Coral Skeleton

Finger corals are a dominant species in the Caribbean, Florida, Bahamas and Indo-Pacific ocean reefs which form some of the largest colonies extending as high as 8 meters (26 feet) tall. They are a very slow growing form and therefore some may be a thousand years old!

Because the finger coral skeleton sample in my possession has broken off branches (very typical) I was unable to identify the exact species, but am certain it belongs to the genus called, Porites. Described below are threee Western Atlantic Porites species possibly a match for my sample!

Club Tip Finger Coral

Club Tip Finger Coral (Porites, porites) possess thick, stubby branches growing upright or spread wide apart. Club finger coral are a hardy stony coral featuring thick, blunt-tipped branches in varying shades including green, blue-gray, pink, purple or cream. They are commonly found in the Caribbean, Florida, Bahamas, and the Indo-West Pacific reef coasts. They require high lighting environments with strong water flow, and stable reef boundaries.

Branching Finger Coral

Branching Finger Coral (Porites, furcata) possess elongated, tightly compact slender branches with rounded blunt or bulbous tips. It forms dense, bushy clumps; most commonly browns, tans, and yellowish hues, but they can also appear in green, blue pink and grey; a fast-growing coral often found in shallow Caribbean, Florida and Indo-Pacific reefs. They require high-intensity lighting and medium-to-strong water flow.

Thin Finger Coral
Source

Thin Finger Coral (Porites, divaricata) possess the most slender branches of the three; are widely spaced apart, often divided at their flattened or clubbed tips. Colors vary from purple, grey, yellowish-brown to pinkish-brown. Thin Finger coral is a small Caribbean stony coral typically forming small colonies, often found in shallow, high-sediment environments like seagrass beds and protected reefs.

FINGER CORAL CLASSIFICATION

Kingdom: Animalia
Phylum: Cnardia (stinging cells)
Class: Anthozoa (flower animl)
Order: Scleractinia (stony coral)
Family: Poritidae (massive reef builders)
Genus: Porites (finger-like)

Fossilized Algae

March 11, 2013 by Fossillady

Did you know algae are the oldest fossils found on Earth that can be seen with the naked eye?

I have picked up several fossilized samples of algae from Lake Michigan’s Oval Beach in Southwestern Michigan (USA) shown below. Algae come in a variety of shapes and forms. They range from single-cell organisms, such as microscopic phytoplankton and diatoms, to multicellular bodies, such as in the case of giant kelp that can grow as tall as 65 meters (200 feet).

Fossilized Algae found on Oval Beach, Saugatuck, Michigan, USA

Why is algae important to you and me?

The answer to the question is that algae are the most important photosynthesizing organisms on Earth! A byproduct of photosynthesis is oxygen. Algae produces more oxygen from the sun’s energy than all other plants combined.

They also form a beneficial partnership with other organisms such as with reef building coral, which over time, constructs limestone.

Fossilized algae has been dated as far back as 1.7 billion years ago.

Flip Side of Fossilized Algae Shown Above

Shown below is a sample of petrified algae I purchased years ago that was tumbled and polished smooth. This algae once flourished in warm seas over what is now the US state of Minnesota. It is estimated to have lived nearly two billion years ago. The algae has been petrified or replaced with jasper. Jasper is a type of quartz that is dense and finely grained with up to 20% foreign materials that determines the color.

Petrified Algae replaced with Jasper

Algae are defined as a group of predominantly aquatic, photosynthetic, and nucleus-bearing organisms that lack the true roots, stems, leaves, and specialized multicellular reproductive structures of plants.

Fossilized Algae Found on Lake Michigan Beach

Ten thousand years ago, the glaciers scraped up Devonian aged seabed creating the Great Lakes. In the processes, they released thousands of unburied treasures, including fossilized algae, that continually wash ashore, and today, we humans enjoy the privilege of discovering the secrets of their past.

Fossilized algae molds found along Lake Michigan shores embedded in claystone infused with iron.