Fascinating fasciation and other casuarina growths

Wow! what a weird, spectacular mutation!

That was my first thought when I noticed an amazing expansion and deformation of the growing tip of a young casuarina at the top of Red Hill in Canberra.

I had just begun the December 2010 quarterly survey of Red Hill as part of the Canberra Ornithologists Group Woodland Bird Survey when I came across it on the side of the track. And luckily I had my camera with me on that occasion. I hadn’t seen anything quite like it before; nor since.

The fasciated growing tip of a casuarina (Allocasuarina verticillata) in Canberra.

A less extreme (or earlier in development?) example of fasciation on the same casuarina.
For a size estimate, the ant (a common Sugar Ant Camponotus consobrinus) is about 15 mm long. 

These exceptional growths are the result of a process called fasciation which, although rare, is common enough that the condition is well known in a wide range of plants. Indeed some plant cultivars have been developed, especially of certain cacti, daisies, and the cockscomb (Celosia argentea), specifically for this ‘feature’ (see for example http://wimastergardener.org/?q=fasciation ).

The word comes from the Latin fascia meaning ‘a band’, and alludes to the typical broad flat ribbon-like structures that commonly result. Although this broad banding is perhaps the most common pattern, fasciation can also manifest as radial or adventitious additional flowers growing out of the main flower, sometimes referred to as ‘hen and chicks’. I wish I’d known this earlier this year when I had several orange daisies in the front garden with this condition – I thought at the time it was just how they grew, but since then they’ve all been quite normal!

In simple terms, fasciation results from the abnormal growth of the meristem tissue (i.e. the growing tip of the plant, be it stems, flowers, roots etc). The underlying reason for this may be physical damage (including frost damage), insect damage, bacterial, viral or fungal infections, hormonal imbalances, or genetic mutation. 

It seems that casuarinas, and particularly the Drooping She-oak Allocasuarina verticillata, may be prone to such fasciation – see for example http://www2b.abc.net.au/science/scribblygum-old/posts/topic9591.shtm , and especially http://medlarcomfits.blogspot.com.au/2007/08/more-views-of-that-casuarina.html for some incredible photos.

In fact, Casuarinas seem to be prone to quite a range of growth abnormalities other than fasciation. Below are some examples of a range of ‘defects’ I’ve noticed in several different casuarina species over the past couple of years. These generally have been small and unobtrusive, and presumably result from some similar perturbation to the growing tip of the plant (or might they be insect-induced galls?). 

Abnormal growth in a casuarina, Harrington NSW, July 2012.

Abnormal shoot growth (or gall?) in a casuarina, Harrington NSW, July 2012.

Abnormal shoot growth (or gall?) in a casuarina, Cessnock NSW, February 2014.

Another well-known growth abnormality in trees is what is known as ‘witches’ brooms’. These show up as a dense cluster of shoots arising from the one spot, often resembling a clump of mistletoe. Again, the causes for these growths may be varied, and may relate to infection by rust and other fungi, viruses, bacteria, mite or insect damage, or even mistletoes.

So to come full circle, on the latest Red Hill woodland survey, done just last Friday morning, I photographed the example below. Clearly, it had been growing in this tree (again an Allocasuarina verticillata) for quite a while – the witches’ broom is a bit over a metre in length – but, despite hanging right over the main access road, this was the first time I had really noticed it. Perhaps because I had this blog post in mind!

A pendulous witches' broom in an Allocasuarina verticillata on Red Hill, Canberra, ACT, September 2014.

The witches' broom is a dense clustering of twisted, shortened, casuarina needles.

So I’ll keep my eye out for further growth abnormalities in casuarinas (and other plants). And while I’m at it, perhaps I should get myself a copy of a recent book by Rosalind Blanche that sounds really interesting called Life in a Gall: the Biology and Ecology of Insects that live in plant galls. Galls really are another story entirely…

Cape Dragonflies

There are 324 species of dragonflies and damselflies in Australia! And over 5,000 worldwide. 

They all belong to the insect Order Odonata, which has an ancient lineage stretching back at least to the Upper Carboniferous 325 million years ago - they saw the dinosaurs come and go.

They can be divided into two distinct groups, the damselflies (Zygoptera), and the dragonflies (Epiproctophora = Epiprocta, formerly Anisoptera). In Australia, the damselflies fall into 12 families, and the dragonflies into 18 families (depending on which taxonomy you follow!).

Damselflies tend to be very slender, graceful, and generally hold their wings closed along their abdomen, whereas dragonflies are comparatively robust and hold their wings flat and perpendicular to their bodies.

On a bird banding trip come family holiday to Cape York and the Cairns area in far north Queensland in Nov-Dec 2011, I opportunistically photographed 12 of the 324 Australian species, representing one of the damselfly families and four of the dragonfly families.

Diphlebiidae

This is a small family, sometimes known as the 'azure damselflies' or 'rockmasters'. Unlike most damselflies, they hold their wings away from the body, like some sort of wayward helicopter, rather than closed along the abdomen.  It comprises just two genera: Philoganga from South-East Asia (4 species), and Diphlebia (5 species) which is restricted to the east coast of Australia except for one species that extends to New Guinea. Their habitat is streams and rivers.

The Tropical Rockmaster Diphlebia euphoeoides occurs in far north-east Queensland (and yes, this is the one that also extends to New Guinea), and inhabits streams and rivers, including those that may dry to pools. Mature males have extensively darkened wings; the first two photos below are of young males with relatively clear wings. Females are golden-brown in colour rather than the striking blue and black of the males. In my experience, which is limited, these appear to be quite common as I saw them at Mt Hypipamee on my first trip to the region in Nov 2005, and again at several places on the 2011 trip; always near fast flowing rivers. They're stunning!

Tropical Rockmaster Diphlebia euphoeoides (Diphlebiidae),
Mossman Gorge, 30 Nov 2011.

Tropical Rockmaster Diphlebia euphoeoides (Diphlebiidae),
Mossman Gorge, 30 Nov 2011.

Tropical Rockmaster Diphlebia euphoeoides (Diphlebiidae),
Woogabba Creek, Bloomfield, 26 Nov 2011.

Tropical Rockmaster Diphlebia euphoeoides (Diphlebiidae),
Woogabba Creek, Bloomfield, 26 Nov 2011.

Tropical Rockmaster Diphlebia euphoeoides (Diphlebiidae),
Woogabba Creek, Bloomfield, 26 Nov 2011.

Telephlebiidae

This family includes 39 species in eight endemic Australian genera (and as far as I’ve been able to determine only occurs in Australia). It is essentially a family of eastern Australia, though there is a single species in WA, and the adults are generally known as the ‘southern darners’. Its status as a family, rather than being treated as a subfamily of the Aeshnidae, is disputed by some. They are large, slender dragonflies that are associated with running fresh water from tropical rainforests to alpine environments, and even sand dunes.

The Green-striped Darner Austroaeschna forcipata occurs in far north-east Queensland, where it is largely restricted to rainforest streams. The one below certainly fitted this criterion as it hung immobile in the dense shade of rainforest plants adjacent to a tiny creek near our mountain accommodation in the Daintree. 

Green-striped Darner Austroaeschna forcipata (Telephlebiidae),
Daintree, 29 Nov 2011.

Lindeniidae

This family, the ‘tigers’ or 'wingtails' is recently split from Gomphidae, an action which is far from universally accepted by taxonomists. They are medium-sized to large black and yellow dragonflies, with clear wings, and the eyes are distinctively widely separated, never meeting on top of the head. This latter characteristic is more typical of damselflies. The family is represented in Australia by just three species of Ictinogomphus, all endemic,  but the genus is represented by a further 13 species in Africa and Asia.

The Australian Tiger Ictinogomphus australis inhabits both flowing and still waters - rivers, riverine lagoons, lakes, and ponds - throughout eastern and northern Australia. The one below was photographed at the Cattana Wetlands in northern Cairns. 

The other two Australian species are more localised; one to the northern tip of Cape York, the other to the Pilbara.

Australian Tiger Ictinogomphus australis (Lindeniidae),
Cattana Wetlands, Cairns, 28 Nov 2011.

Gomphidae

Commonly referred to as ‘clubtail dragonflies’, or just ‘clubtails’, this is a large family of about 90 genera and 900 odd species worldwide. They also have widely separated eyes. Most species are associated with flowing streams or rivers. Seven genera, of which five appear to be endemic, account for the 36 species in Australia.

The Zebra Vicetail Hemigomphus comitatus occurs along streams and rivers in far north-eastern Queensland. The ones I saw were on Woogabba Creek, in the rainforest to the east of Wujal Wujal and a little south of the Bloomfield River (the banner photo at the top of this post shows the habitat). 

Zebra Vicetail Hemigomphus comitatus (Gomphidae),
Woogabba Creek, Bloomfield, 26 Nov 2011.

Zebra Vicetail Hemigomphus comitatus (Gomphidae),
Woogabba Creek, Bloomfield, 26 Nov 2011.

The Rainforest Vicetail Hemigomphus theischingeri also occurs only in far north-eastern Queensland, but unlike the Zebra Vicetail appears to be restricted to rainforest streams. I saw both the Zebra and the Rainforest together at Woogabba Creek. 

Rainforest Vicetail Hemigomphus theischingeri (Gomphidae),
Woogabba Creek, Bloomfield, 26 Nov 2011.

Libellulidae

This is the largest family of dragonflies, with well over a thousand species in about 140 genera worldwide. It includes the ‘skimmers’, the ‘perchers’, ‘gliders’, and their allies, many of which are brightly coloured and obvious, and represent the most commonly seen dragonflies. Despite their prevalence, they are comparatively under-represented in Australia, which has a more Gondwanan bias to its dragonfly fauna, but there are nevertheless around 50 species of Libellulidae in Australia.

The Striped Swampdragon Agrionoptera longitudinalis is associated with shady pools and tree holes, again from far north-eastern Queensland, but also extending into New Guinea. The one below was in the same Daintree rainforest garden as the Green-striped Darner above - it was a very profitable two-night stay for us (or at least for my dragonfly photo 'collection') and lived up to its name of Eden Escape.

Striped Swampdragon Agrionoptera longitudinalis biserialis (Libellulidae),
Daintree, 29 Nov 2011.

The Australasian Slimwing Lathrecista asiatica has a distribution stretching from India, through South-East Asia, to northern and north-eastern Australia; the Australian subspecies, festa, apparently being endemic. Based on the number of photos picked up by Google Images, this appears to be a fairly common species, and adults may be encountered far from water as well as near streams, rivers, lagoons and swamps. The ones I saw were in rainforest clearings at several places in Iron Range National Park (now called Kutini-Payamu NP). The females look quite different to the brighter red and green males. 

Australasian Slimwing Lathrecista asiatica festa (Libellulidae),
West Claudie River, Iron Range NP, 23 Nov 2011.

Australasian Slimwing Lathrecista asiatica festa (Libellulidae),
Scrubby Creek, Iron Range NP, 22 Nov 2011.

Australasian Slimwing Lathrecista asiatica festa, female, (Libellulidae),
Scrubby Creek, Iron Range NP, 22 Nov 2011.

The Green Skimmer Orthetrum serapia is a species that prefers a variety of still or sluggish waters, and is distributed from the Philippines, through the south-west Pacific, and across far north-eastern and northern Australia. It is markedly different in appearance to several other species in the genus such as the common and widespread Blue Skimmer Orthetrum caledonicum, a chalky-blue dragonfly (at least the male is) that I seem to see pretty much wherever I go. The Green Skimmer I saw, very briefly, was at the Cattana Wetlands in northern Cairns, and the posture of this one, in the only photograph I managed to get, made it quite difficult for me to figure out what species it was. 

Green Skimmer Orthetrum serapia (Libellulidae),
Cattana Wetlands, Cairns, 28 Nov 2011.

The Painted Grasshawk Neurothemis stigmatizans is another common dragonfly that I saw in lots of places around Iron Range NP, the Daintree region, and have also previously seen around Darwin and Litchfield National Park. They are very distinctive and immediately recognisable. They occur across the Top End and down the Queensland east coast (as well as to the north of Australia), breeding in a range of still waters, and are frequently seen congregating in clearings or grassy areas.

Painted Grasshawk Neurothemis stigmatizans stigmatizans (Libellulidae),
West Claudie River, Iron Range NP, 23 Nov 2011.

Painted Grasshawk Neurothemis stigmatizans stigmatizans (Libellulidae),
West Claudie River, Iron Range NP, 23 Nov 2011.

Painted Grasshawk Neurothemis stigmatizans stigmatizans, female, (Libellulidae),
Daintree, 29 Nov 2011.

The Graphic Flutterer Rhyothemis graphiptera is also instantly recognisable and the ones I saw lived up to the name as they fluttered above and between the reeds at the edge of Lake Barrine in the Atherton Tablelands. They occur around riverine lagoons, lakes, ponds and swamps across much of Australia, and also in the Moluccas, New Guinea and New Caledonia.

Graphic Flutterer Rhyothemis graphiptera (Libellulidae),
Lake Barrine, Atherton Tablelands, 2 Dec 2011.

I first saw a Yellow-striped Flutterer, Rhyothemis phyllis, at the settling ponds of the Lockhart River sewage works (sewage works are always a great place for birds and dragonflies!) and was stunned. I hadn't seen a dragonfly anything like this before, but it was early days and I saw lots more of them in various places over the course of the trip. This species prefers a range of still waters, and apart from occurring across the Top End and eastern Queensland, is also found from Burma (Myanmar) to the western and southern Pacific. 

Yellow-striped Flutterer Rhyothemis phyllis (Libellulidae),
Cattana Wetlands, Cairns, 28 Nov 2011.

Yellow-striped Flutterer Rhyothemis phyllis (Libellulidae), 
Lockhart River, 22 Nov 2011.

And finally, the Common Glider Tramea loewii. This is a very common and widespread species in Australia and, unlike most of the species featured in this post, I'd seen it many times previously in all sorts of places. This one was at the Cattana Wetlands in Cairns. They utilise a wide range of still waters but I've also seen them far from water and they are clearly happy to fly large distances. They have a wide distribution stretching from the Cocos Islands, across Wallacea and New Guinea, to New Caledonia and the western Pacific

Common Glider Tramea loewii (Libellulidae),
Cattana Wetlands, Cairns, 28 Nov 2011.

My main reference for dragonflies is The Complete Field Guide to Dragonflies of Australia by Gunther Theischinger and John Hawking (CSIRO Publishing, 2006) - a really excellent guide and resource. They follow a tendency to 'split' families as taxonomic research advances, but as touched on above, the revisions are not necessarily accepted by all authorities (nothing new there!) For me, irrespective of any taxonomic or ecologico-political reasons, splitting at least gives a better 'feel' for the relatedness of the different species and groupings. 

Below I've included a table that I compiled, mainly for my own benefit, that lists the odonate families that occur in Australia and indicates the number of genera and species in each (also just for Australia - and bearing in mind that such numbers are constantly in flux, due as much to differences in taxonomic opinion as to advances in research, and are, in the end, and to use an often-used expression of a friend of mine, just a human conceit!).

Another great resource is the Identification Guide to the Australian Odonata put out in 2009 by the NSW Department of Environment, Climate Change and Water (available as a pdf at http://www.environment.nsw.gov.au/resources/publications/09730AustOdonata.pdf ), and it's worth having a look at  at Australian Damselfly and Dragonfly Photography at  http://dl.id.au/g.php?c=3

Happy dragon-watching!

Traditional	Theischinger and Hawking 2006	Group Name (T&H 2006)	Genera	Species
Suborder Zygoptera	Suborder Zygoptera	Damselflies	37	113
Diphlebiidae	Diphlebiidae	Rockmasters	1	5
Chlorocyphidae	Chlorocyphidae	Jewels	1	1
Calopterygidae	Calopterygidae	Demoiselles	1	1
Hemiphlebiidae	Hemiphlebiidae	Greenlings	1	1
Synlestidae	Chorismagrionidae	Relicts	1	1
	Synlestidae	Sylphs/Malachites	2	6
Lestidae	Lestidae	Spreadwings/Reedlings	3	14
Lestoideidae	Lestoideidae	Bluestreaks	1	4
Megapodagrionidae	Megapodagrionidae	Flatwings	5	22
Protoneuridae	Protoneuridae	Threadtails/Pinflies	1	12
Isostictidae	Isostictidae	Narrow-wings	7	15
Coenagrionidae	Coenagrionidae	Pond Damsels	13	31
Suborder Anisoptera	Suborder Epiproctophora, infraorder Anisoptera	Dragonflies proper	75	211
Petaluridae	Petaluridae	Petaltails	1	5
Austropetaliidae	Archipetaliidae	Tasmanian Redspots	1	1
	Austropetaliidae	Mainland Redspots	1	2
Aeshnidae	Telephlebiidae	Southern Darners	8	35
	Aeshnidae	Hawkers	7	13
Gomphidae	Lindeniidae	Tigers/Wingtails	1	3
	Gomphidae	Clubtails	7	36
Synthemistidae	Synthemistidae	Tigertails/Southern Emeralds	8	26
Corduliidae	Gomphomacromiidae	Urflies	1	2
	Pseudocorduliidae	Mistflies	1	2
	Macromiidae	Cruisers	1	2
	Austrocorduliidae	Southern Hawks	5	10
	Cordulephyidae	Shutwings	1	4
	Oxygastridae	Streamcruisers	1	1
	Corduliidae	Emeralds	2	2
	Hemicorduliidae	Modern Emeralds	2	11
Libellulidae	Urothemistidae	Baskers	3	4
	Libellulidae	Skimmers/Perchers	24	52