
A.E. Eaton first described our most dominant Kossie Dun, Coloburiscoides
haleuticus way back in 1871. It has a wide distribution, which covers
most of New South Wales and all of Victoria. Officially there are two
other described species in this family, C.munionga and C.giganteus.
Tillyard first described munionga in 1933. Its distribution is along
the east coast from just over the border of Queensland and follows the great
divide right to the Victorian border.
The third species, C.giganteus, is also found along the same distribution
areas as C.haleuticus. C.giganteus is the largest of our Mayflies and
loves those very small, high country streams. It is huge, in total
around four centimetres. Strangely this family is not known in
Tasmania.
C.haleuticus and C.munionga tend to emerge from November and in the Upper
Murray, Mike used to say, it fades away around January. Yet on the
streams around Eildon in central North East Victoria we see it hatch out
around November for about a month to six weeks, and then it disappears, only
to re-emerge in lesser numbers around March (autumn in Australia) and
continues to emerge for at least another month.
The Kossie Dun is quite large and apart from its size, it is easy to recognise. The nymphs, which belong in the swimming category, are around 20 to 25mm long and tend to inhabit the fast flowing riffle water found on most of our mountain streams. The have hairy filaments on their tails to assist in swimming and holding ground against the current.
On some waters, such as the Goulburn River, we can at times in the early part of the season get some quite heavy hatches, whilst on some of our smaller streams such as the Rubicon and the Steavenson, we can experience regular but very light hatches of this fabulous Mayfly.
KOSCIUSZKO DUN – As developed by Mike Spry
Hook: 10 down eye (MustadR50 or Partridge Dry Fly)
Tail: Buff-coloured hackle fibres
Body: Tapered buff polypropylene twist
Wings: Buff hackle tips
Hackle: One or two buff cock hackles
Both flies tied by Mike Spry
Para-Kossie Dun (C.munionga or Olive Kossie) as designed by
Mick Hall
Hook: Partridge Dry Fly
Size: 10-8
Tail: A bunch of Coq de Leon Cock Saddle Hackle fibres
Body: Cream Antron Dubbing
Post: Cream Enrico Puglisi Silky Fibres
Hackle: Whiting Farms Golden Badger Cock Saddle tied full.


Kossie Dun Traditional as designed by Mick Hall
Hook: Partridge Dry Fly
Size: 10
Tail: A few strands of Coq de Leon Cock Saddle fibres
Body: Buff-coloured dubbing
Wings: Bronze Mallard breast feather
Hackle: Whiting Farms Golden Badger Saddle Hackle tied full.
The Olive Kossie Dun, A New Species?
Along the Goulburn River we often see some great hatches of the Kossie Dun
and back in November 2006 Warryn Germon and I came across what we believe to
be another species of this great family.

At first glance of the Olive Kossie, you could be forgiven in thinking they were the same species and maybe this is why it has not been picked up before.



Some History
The first mention of our Kossie Dun that I can find from a flyflicker’s
perspective is in Howard Joseland’s Angling in Australia and Elsewhere,
published way back in 1921, where he writes of the great red spinner and
large grey duns, stating: 'One sees occasionally, about December, a fly
resembling an English May fly, which has been named the “Great Red Spinner”;
I am not sure whether it is an imago or sub-imago, that is, one of the
ephemeridae in its first or second stage after development from the pupa.'
Further on he states: 'Since writing the above, I witnessed an
extraordinary rise of duns (ephemeridae)on the 7th and 8th of November.
In the middle of the first day clouds of small duns hatched out on the
Murrumbidgee and were wafted along by the breeze. The rapid water over
which they passed, however, was barren of trout, as a fresh had, I feel
sure, driven the rainbows to the deep eddies at the head of the pools.
In one of the eddies the following evening, after a hot day, and as soon as
the water was overshadowed through the sun disappearing behind a hill,
larger duns, with grey bodies, emerged mysteriously in clouds from the
water, and at once a number of trout broke the surface, chiefly with tails
showing. The fact that they would not take my counterfeit till it had
sunk, indicated that they were feeding on the pupae as they rose to the
surface before emerging in the beautiful fairy forms of the sub-imago, or
first state of their flying existence. A collection of these flies
would have revealed many types synonymous with those of the English rivers.'
Unfortunately, for some reason Joseland did not give a pattern for the large
Grey Dun but he did for its spinner, which is one of many versions of a very
old English pattern first published by Alfred Ronalds in his The
Fly-Fishers Entomology, 1836.
The Olive Kossie Dun, as we call it, is not unlike C.haleuticus to look
at but it does have some olive tonings, as you can see if you compare the
eye caps of both species. When comparing you will notice that there
are other subtle differences like a tinge of terracotta along the back of
C.haleuticus compared to beige tonings on our Olive Kossie. The big
difference between the two is that the spinner of this species is a true
olive and as a comparison, it is very close to the colour of olive oil to
look at, whereas C.haleuticus and C.munionga are a red/orange or terracotta
to look at.
I sent a photograph of the Olive Kossie Spinner over to a friend of mine,
Ray Brown, who now lives in Tasmania and is also into bugs. Cheekily
he named it C.trickimikus! But all jokes aside, the Olive Kossie is
one great looking bug. As soon as we first saw the olive spinner I had
thoughts of imitating it and the pattern that I came up with is as follows:

GREAT RED SPINNER (wet-fly)
Body: Light red fur
Hackle: Red
Wings: Grizzle hackle tips dyed red
Tail: Red fibres
Looking at the list of fly patterns listed; there is another that may
represent the large grey dun. The fly is called the Tuross, which was
designed by Joseland. The tie is listed as follows:
TUROSS (wet or dry)
Body: Grey-green fur
Hackle: Cinnamon
Wings: Buff Orpington
There is no mention of a tail with this description, however on the previous
page we see a drawing of the Tuross carrying what looks like red-brown
hackle fibres as a tail. For either pattern you will note that hook
sizes were not mentioned.

Kossie Wulff - As adapted by Mick Hall
Hook: Partridge Dry Fly
Size: 10
Tail: A bunch of Moose mane fibres
Body: Cream Antron and touched along the back of body with a Light Oak
(Terracotta) marking pen
Wings: Calf Tail
Hackle: Whiting Farms Golden Badger Saddle Hackle tied full
Notes: If the back of the body is treated with a beige coloured making pen,
you have a very close representation of the Olive Kossie Dun

Female C.haleuticus
Little did the late Mike Spry know that when he put the name “Kosciusko Dun” to the large grey duns that appear on the streams around Khancoban, the name would stick and become the common generic term for this fabulous Mayfly. Since that time the Kossie Dunn, our largest Mayfly, has been escalated to icon status right alongside that of the Lambda Dun and its Red Spinner.
For over two decades Mike ran his guiding service, rafting the river and
conducting his very popular fly-fishing courses. I first met Mike back
in the very early 1970s whilst he was still living at Deniliquin and it was
a long, distant friendship that lasted until his passing. Whenever I
was in the region we would make some time for each other to chat about all
things piscatorial, that which a couple of old flyflickers do.
A couple of years before Mike’s passing, I talked him into giving me a
sample collection of fly patterns that he had tied and developed for his
region and included within that collection were samples of his caddis, his
shaggy brown nymph and his Kosciuszko Dun and spinner. Please note these
shots are of flies from Mike’s fly box. They are purely fishing flies
and not tied for photographic purposes.
His patterns are as follows:


KOSCIUSZKO ORANGE SPINNER
As developed by Mike Spry
Hook: 10 down eye (Mustad R50 or Partridge Dry Fly)
Tail: A few strands of light brown cock hackle fibres
Body: Orange floss
Ribbing: 4 turns of gold tinsel
Hackle: Light brown cock hackle, tied full Wings: Nil
It should be noted that Mike Spry was in many ways a believer in presentation over imitation, as many flyflickers are. It should also be noted that the distribution of both C.haleuticus and C.munionga overlap in and around the Snowy Mountains as well as around Khancoban. They are very similar and it would not surprise me if Mike had put together his patterns to cover the dun and spinners of both species.



The Olive Kossie Spinner as designed by Mick Hall
Hook: Partridge Dry Fly
Size: 10
Tail: A bunch of Whiting Farms Coq de Leon Cock hackle fibres
Body: Cream knitting yarn that has a clear Antron type fleck running through
it and dyed Olive with a marking pen.
Post: Cream Enrico Puglisi Silky Fibres
Hackle: Tied Parachute fashion, Whiting Farms Golden Badger Saddle Hackle.
Notes:
1. It should be noted that the emergent period of the Olive Kossie Dun
only lasted around three weeks and was not seen again for that season.
The pattern listed is largely untried but I suppose we have to start
somewhere.
2. The knitting yarn was purchased from our local haberdashery. I
chopped a handful up into one-centimetre pieces and put them through a
$20.00 coffee grinder that was purchased at K-Mart. The clear flecks,
even when stained with the olive marking pen, helped in obtaining a
translucency to the dubbing. As a substitute, clear or cream Antron
would do the job if you can’t find a suitable olive.
The dun is so similar to C.haleuticus, just a little lighter and I believe
Mike’s pattern would suffice. However I would tend to tie it with a
Parachute hackle. I have listed below a few of my favourite patterns,
including a Para-Kossie.