Fred the Thread

In 2003, Corinne Watts was standing in a Waikato domed peat bog (as wetland scientists sometime do) contemplating the stems of giant cane-rushes Sporadanthus ferrugineus.

She chanced upon lovely squiggly lines decorating the stems of Sporadanthus ferrugineu. and wondered who might be the artist responsible. Opening up stem after stem, she discovered amazingly thin, long thread-like larvae of a reddish orange colour, and the legend of Fred the Thread was born.

Fred has no legs, but he does have a hinged head-capsule (a ‘flip-top’ head) to allow him to eat his way along inside of the very thin stem. No entomologist (insect scientist) could work out what type of insect the Fred larvae belonged to; lepidopterists (moth and butterfly scientists) thought they were Coleoptera (beetles); coleopterists (beetle scientists) thought they were Diptera (flies); no dipterists (fly scientists) could be found to comment, even with the aid of Malaise traps.

Eventually Corinne and a lepidopterist colleague reared the beasties through to adulthood, and lo and behold, they were indeed moths (Lepidoptera)!  The moth was named Houdinia flexilissima from its very thin flexible larva, and its remarkable escape from the tight confines of the Sporadanthus stem.

 

Lepidopterist Robert Hoare wrote this poem in Fred’s honour.

Fred the Thread

I have a friend (his name is Fred)
He’s thinner than a cotton thread
His colour is an orange-red
He doesn’t feed on jam or bread
But Sporadanthus stems instead.
Such narrow tunnels must he tread
He needs a hinge inside his head
To give his jaws the room to shred
The food that is his home and bed
And stop himself from dropping dead.

Now when our friend is fully fed
And knows the time has come to shed
His final skin, a sense of dread
Begins to filter into Fred:
How fast, he thinks, the time has sped!
And what a sheltered life he’s led!
He hopes he’ll have some outdoor cred
And won’t be thought of as inbred.
He sloughs his skin from A to Zed
And there’s a pupa in his stead!

Three weeks have passed, and it’s incred
ible to see the adult Fred,
A mothy person born and bred
To look like that on which he’s fed.
He shows an admirable ded
ication to his art, his sed
entary posture leaving ed
ucated mothmen ruby-red,
The effort of locating Fred
Causing a rush of blood to head
Resulting in potential med
ical emergency and bed
With cooling drink and favourite Ted
Until delirium has fled.

To summarize, he’s Fred the Thread,
He’s red and has a hingèd head
His head is used to shred his bed,
His bed’s the food on which he’s fed,
His bed is red and I am led
To think the redness of the Fred
Reflects the bedness of the red
I mean the redness of the bed—
The bed he shreddeth with his head
Until the Fred is fully fed
And sheds the skin he has to shed
To flee the bed that must be fled
To lead the life that must be led
To woo the wife that must be wed
To father further Freds of Thread.
Then Fred can smile and drop down dead.

 I’ve said the things I wanted said.

 ROBERT HOARE: SIX-LEGGED THINGS AND SCALY WINGS

 

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Avondale Spider

The large harmless spider found around the Avondale area of Auckland is an Australian huntsman spider. This spider found its way to New Zealand in the early 1920s, with the first specimen found in 1924. It probably came in imported wood used for railway sleepers. It has not spread very far from Avondale, so it has received the popular name of Avondale Spider. In South Australia this species is quite common, and people encourage them to live in their houses to keep the pest insect population down.

Where found

They are nocturnal and like to hide during the day in dark, dry places. In their natural habitat, which is under loose-fitting bark of wattle trees, they live in large colonies. Around houses they hide in attics, under corrugated iron, behind pictures and bookcases, and in sheds and garages.

Food

These spiders are fascinating to watch. They sit motionless on walls and then rush after prey. They very quickly devour prey, sucking all the juices out and discarding the hard outer pieces. Their favourite foods seem to be moths, flies, cockroaches, and earwigs.

Size

The first reaction of most people on finding Avondale spiders is usually horror. The spiders move very fast when disturbed (as do people when frightened!). Mature spiders with legs outstretched can measure up to 200 mm across (8”).

Life history

The mature males are frequent visitors inside houses in the months January to March when they are looking for a female to mate with. Females are capable of laying up to 200 green eggs in an oval-shaped, white papery-looking egg sac about 25 mm long (1”) by 12 mm wide (1/2”). Females guard their egg sac, and after 4-6 weeks open this up to enable the spiderlings to hatch. They will look after the spiderlings for a few more months until they disperse. Spiderlings will feed communally if the prey is too big for them to manage on their own.

Film stars

In 1989/90, 374 Avondale spiders were sent to Hollywood to star in the Steven Spielberg movie Arachnophobia. Delena cancerides is harmless to humans, but it looks fearsome and therefore suited its movie role as a "killer spider".

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Poor Knights Island has some special insects

The Poor Knights weevil adults are unusually long-lived (for a weevil anyway)

• The adult of the Poor Knights weevil, Hadramphus pittospori, has been recorded as living for 3 years: most adults of weevil species of the world do not live more than 1 year.
• The adult is 16-20 mm long.
• The 6 larval stages last about 1 year, and grow inside their host plant karo (Pittosporum crassifolium).
• The pupal stage lasts about 3 weeks, then the adult hatches.
• The long adult life of these weevils is unusual. It is perhaps one explanation why populations of large-sized weevils related to this species are so badly affected by introduced predators such as rodents.

The Poor Knights cave wëtä (Gymnoplectron giganteum) has the longest appendages (legs and antennae) of any New Zealand insect or spider.

• From the tip of the antenna to the end of the hind legs it can measure an enormous 450 mm, although the body is only 50 mm long.
• It hides in caves and rock piles during the day and comes out at night to feed on flowers and lichens.
• It is only found on the Poor Knights Islands (Tawhiti Rahi and Aorangi).

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Tree lobsters of Lord Howe Island

“Tree lobsters” are an enigmatic group of robust, ground-dwelling, stocky-looking stick insects found across New Guinea, New Caledonia and associated islands.  The most famous member is the Lord Howe Island tree lobster, which was believed to have become extinct after rats reached the island earlier this century. In 2001, the conservation world got very excited when a population of barely more than 20 individuals were found on Ball's Pyramid, a very small, 200 metre wide rock about 25 k from Lord Howe Island. They were one of the rarest insects in the world.

Thomas Buckley (Landcare Research) and colleagues have recently had a paper published in the prestigious British journal Proceedings of the Royal Society, and this paper shows that the story is a particularly intriguing and complicated.

Thomas and his colleagues constructed DNA-based phylogenies* not just for the Lord Howe tree lobsters, but also for all the major stick insect lineages across the Australasian region. Instead of being related to the New Guinea lineages as everyone expected, the molecular analyses indicated they had diverged from an unrelated Australian lineage of stick insects more than 22 million years ago!  Because Lord Howe Island emerged as the result of volcanic activity only 6.4-6.9 million years ago, these tree lobsters could not have originated there.  It appears that the Lord Howe Island tree lobster may have evolved on the now drowned islands, the oldest of which is 23 million years, to the north of Lord Howe and progressively dispersed down the island chain, leaving ancestral populations to come extinct as their islands eroded away.

While that may explain the time paradox, it does not explain why the Lord Howe species look more like the unrelated New Guinea lineages.

Thomas believes that is due to convergent evolution, where similar traits are acquired independently. Their data indicate tree lobster body form evolved independently on the three isolated landmasses of New Guinea, New Caledonia and Lord Howe Island. Their overall uniformity of body shape and behaviour is probably the product of similar selective pressure associated with ground-dwelling life.

*A phylogeny, sometimes called an ‘evolutionary tree’, shows how groups of organisms have evolved, progressively branching away from a common ancestor.  Hence a phylogeny describes the relationships between groups of organisms. DNA-based phylogenies are infinitely more sophisticated than anything Charles Darwin envisaged.

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WooHooo! BioBlitz is back!

(Well ... it will be back at the end of March 2012. This time it is in the Auckland Botanic Gardens, Manurewa)

WHAT?

BioBlitz is a two-day scientific race against time.

It’s fascinating, fun, family-friendly and its free!

The goal is to find and count as many species as possible in 24-hours searching time in a large urban park or reserve. We expect to find 1000-1500 species.  This requires many teams of scientific experts. (In fact you seldom find so many biologists in an urban park but we don’t count each other).  Each team specialises in one group of organisms or micro-organisms, and you’d be hard pushed to find something they don’t know about their group.

 

WHEN?

Friday 30^th March 9 am – 11 pm

Saturday 31^st March  7 am – 5 pm. 

WHERE?

“Base camp” will be in a large marquee in the North West area of the gardens.  Pedestrian and vehicle access is best from the Everglade Drive northern entrance to the Gardens, via Manakau / Redoubt Road motorway off-ramp.   

Base camp is the hub of activity where identifications are made, species tallied, and public get to look down microscopes, chat with scientists, and 'ooh' and 'aah' over the beautiful, the curious and the downright thrillingly ugly.  Field trips (guided walks) depart from here.

There will be the usual guided ‘walks & talks’ with experts, including the ever-popular night time events: moths with ‘Dr Robert’ (who uses a super bright special lamp to lure them in) and the nocturnal walk with ‘spider woman Grace’ (most spiders come out to hunt at night and their eyes shine in the torch light).

 WHO CAN COME?

Everyone!

BioBlitz is suitable for people of all ages. It is a family friendly event. There is no charge.

• If you intend going on a ‘walk & talk’ with a scientist, please wear sensible shoes and clothes. If you are coming on one of the ‘after dark’ excursions, please wear sensible warm clothes and bring a torch (families should bring several torches if possible).
• Specialist scientific equipment is loaned especially for the event. This equipment is very expensive and should be treated with care and respect at all times.
• Young children should be supervised by an adult.
• Dogs should be on leads and supervised by an adult.
• The Botanic Gardens & all that lives there must be treated with care and consideration.

WHO IS ORGANISING BIOBLITZ?

Landcare Research is a Crown Research Institute (CRI).  We’ve been involved in organising BioBlitz events in New Zealand since 2004, and we partner with Auckland Museum, universities, other CRIs, local government, the Department of Conservation, and people from interest groups so that we get as many biologists participating as possible.

The principal organizers of BioBlitz 2012 are Landcare Research, the Auckland Botanic Gardens and the Manakau Beautification Charitable Trust.  The Auckland Museum and DOC are represented on the organizing committee.  Forest and Bird Society, Ornithological Society, the Botanical Society, University of Auckland, Unitech, Oratia Native Plant Nursery, and WaiCare are also participating. 

BioBlitz events are conducted in many countries. We’d love to hear from others involved in BioBlitz events in other countries!