Tag: latin

Going out on a limb

In identifying a plant one is often making a guess. An educated guess is still a guess and sometimes there is no correct answer. Many of the banksias belong to groups known as complexes. Members of the complex are seen as separate species but they can also hybridise – meaning that they may have intermediate forms. Any one plant may have a variety of different features, sometimes typical, sometimes weirdly different. Sometimes the scientific name serves to obscure the identity of a plant, take Banksia oblogifolia, it is supposed to have oblong shaped leaves, where the tip is blunt and the base of the leaf is relatively broad. As it happens the leaf shape is variable, and the most reliable identifying feature is a rusty coloured felt that covers the midrib and young branches. The scientific name may endure even if it is misleading because the history of the name is seen as important. The type specimens of banksia oblongifolia may have had particularly oblong leaves, but specimens from further afield may not fit in the box.

banksia oblongifolia

Bus Stop banksias

Behind the artfully decorated Maianbar bus stop there are half a dozen species of banksia within a short walk. To identify them it is handy to learn their names. The information within the name will jog the memory each time you try to identify a plant. Plants may have a common name and a scientific name, both names can be useful. The common name is least reliable, it will vary from place to place and can be pretty vague. The scientific name will slot the plant into the taxonomic hierarchy which will tell you much about the structure of the plant and how it relates to others. The scientific name can change when academics get busy, but it will lead back to the first scientific description of the plant. The scientific name is a double-barrelled binomial usually composed of latin or greek roots or a nod to a dignitary, explorer or a botanist. All of this is useful information.

In the photo below is Banksia spinulosa, the hairpin banksia. The old fashioned hairpin is now an uncommon object and so the common name is possibly not very useful. The generic name Banksia was conjured up in 1782 by Carl Linnaeus the younger, son of daddy Carl Linnaeus the swedish naturalist who invented the taxonomic system. The first half of the binomial honours Joseph Banks who collected the original type specimen in 1770 on Cooks “voyage of discovery”. The second part of the name refers to spines on the leaf tip.

 

Banksia spinulosa
Am liking the common name now that I see what an old fashioned hairpin from 1850 looks like. It has points on the end that would give you a little jab like little spines, whereas the modern bobby pin is not nearly so fearsome. But all jabbing aside the rounded end of either style of pin resembles the bent anthers of the rows of flowers.

 

13-05-17-pic01

Sunset on the Fan Shell?

Here lies the remains of the last Fan shell on Deeban Spit.

Possibly.

Over the last two years the number of Fan shells poking out of the sea grass on Deeban Spit at low tide has plummeted. Where once there was a field of a thousand gaping shells, there are now almost none, and those that do remain are empty.

I miss them.

Empty shells on oyster beds

Fan shells are known locally by the more dramatic, but incorrect name of Razor clams. Yet another animal menace just waiting to extract human blood. They are popular in recipes of an Asian flavour, put “razor clam” in your search engine and cooking pops up first, but you will notice that true Razor clams look like old-school cut-throat razors, while our Fan shells look like fans, or perhaps the ear of a donkey. They are all edible regardless of name.

The big shells out on Deeban Spit  are  Pinna bicolour, bivalve molluscs in the genus Pinna, latin for ear. Pinna bicolour is a widely distributed species named for the bright iridescence of the inner shell. It is restricted to the sandy seagrass beds where the larvae are able to settle and feed. Research done in the warm waters of Malasia and the cooler waters of South Australia shows that they grow quickly and reach 20cm in length in the first year. By the second year they reach 26 cm and they are full size in the third year at 35 cm. Lucky Fan shells may go on to live well over a decade, the old ones gather epibiota, just like the hull of a boat.  Eventually they get tired, weighed down and stop moving. Where the seagrass beds remain there is a good chance the Fan Shells will return.

live fan shell survivor
empty fields empty fields

Snakes and Ladders

The Green Tree Snake is an occasional ground dweller, and when disturbed on the ground it seeks refuge by climbing.  This little snake climbed up a broom handle only to find a dead end.  Now seen back down onto a brick wall and seeking a better  route to the treetops. The Green Tree Snake, Derendrelaphis punctulata,*  is one of four species found in our backyard – all of them are harmless to people.

For the big picture click below.

green tree snake

*Dendra – latin for tree, Elaphe – are another genus of snake, punctulata – fine spotted

http://www.arod.com.au/arod/reptilia/Squamata/Colubridae/Dendrelaphis/punctulatus

Dirty Lizards

There are two distinctly coloured populations of Eastern water dragons living in this corner of Fisherman’s Bay. There are the clean dragons living in the back yard and then there are the dirty dragons that live down by the creek. Clean dragons are grey, flecked with black and white, and dominant males have a distinct red blush on the chest. The rusty dragons live in creek water which carries iron tinged algae. The colour is permanent, but because lizards shed shed their skin a dirty lizard will eventually become clean if it moves away from the creek. The change of colour will take a couple of years to be complete. Some lizards will carry a two-tone appearance for some time.

All dragons like to slumber on a warm patch of their territory. This group of three females and a larger male are taking advantage of a clearing in the ferns where the sun heats the dark soil by the creek. These lizards have been swimming and are now mostly dry, but there is wet patch where one female lizard has been lying on top of the male in the middle. The male can be identified  by his large head. Males wrestle to gain dominance, so there is an advantage to having a large head, or rather, a larger set of jaws.

Which brings us to the latin name of the water dragon; Physignathus lesueurii, where the generic epithet (the first capitalised part of the binomial) refers to a large jaw. The specific epithet refers here to the French artist and naturalist Charles Alexandre Lesueur who traveled with Baudin to Australia in 1801. The Baudin expedition collected over 100000 specimens and many  animals were described from this collection.