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Version: 9.0.819 / Virus Database Hi Bev & Dave, others, Bev: Thanks for the web sites that you included. I don't know Delap's Cove, but I checked Bousfield's manuscript and he visited there in his extensive 2 month survey of the Maritimes. He doesn't record bristletails, but then didn't find them at Harbourville either where they're common (E. L. Bousfield, 1962. Studies on littoral marine arthropods from the Bay of Fundy region. Natl Museum of Canada, Bull. no. 183, pp. 42-62; it's QH1.C13 no183 Sci in Dalhousie's Killam Library). Looking at his habitat descriptions, it seems that he must have concentrated on the beach zone, not the adjacent sea cliffs. As a result, he may have a different species, which he identifies as Petrobius maritimus -- the one on the cliff faces here is Petrobius brevistylis, which in my experience are nearly always females (only males are species-diagnostic). In the sparse literature on Archaeognatha (mostly from UK), cliffs form brevistylis' preferred habitat making them easier to collect, while P. maritimus likes upper beach rubble which renders that species difficult to catch. The two do overlap closely in places, from a study on one of the Scottish isles, St. Kilda. The site nearest to you where Bousfield found them would be further west, in Deep Cove and at Haight Brook, and at Pond Cove on Brier Island, often mentioned here by birders. He also cites Cape Forchu, Yarmouth, where we found 2 mm young ones emerging in the thousands from crevices on the long rock outcrop on the right at the extreme tip, maybe in July (I'd have to check my records). As apterygotes, they can't fly and occupy an extremely restricted niche low on sea cliffs, raising the question of how they got here and distributed so widely, after the last ice age completely covered everything. Bousfield suggests that this sort of fauna may have migrated back from peninsulas and islands in Georges Bank. These were exposed when the sea level was much lower, and may have been ice-free. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Dave: Re. cold-hardy tipulids, interesting, so they must have at least some form of antifreeze protection? The sorts of flies that people breed in cultures (like fruitflies, houseflies, blowflies) have an internal clock as larvae but this speeds up if you raise the temperature up to a point, so the larval period is shorter at 28°C than at 21. If you don't feed them sufficiently in the early stages, they can never catch up and you end up with very small flies (or none -- flies in very small pupae have difficulty eclosing). Where known, emergence is on one of the circadian behaviour cycles, often occurring over a couple of hours in the morning, entrained by the light cycle on which they were reared as larvae. I don't know about tipulids. No, rodents are not at all convenient, at least compared to insects. They require a lot of lab space and technician attention and therefore are very costly to house and rear, especially so as mice have become popular vehicles for genetic work (researchers may have to maintain many strains). Also there's much paperwork: their use is now highly highly regulated and restricted by research organizations in response to political pressure, responding in turn to public perceptions fomented by particular 'animal rights' organizations which members of the public still continue to fund generously. They also smell bad. You might in principle be able to rear tipulids with a lot of effort and garden sods or whatever, but it would require a lot of development and real husbandry and might not succeed even then. At one time, my best guess at the nearest candidate for the ancestor of higher flies was an interesting relict group sometimes called window flies (Anisopodidae). A German researcher did publish on these including on a mutant she had found, but, unusefully, she never published her rearing methods. We'll never know -- a footnote on her last paper records her having been killed in an allied air raid in the 1940s. A while back, I had a go at rearing a local anisopodid, Sylvicola fenestralis, which can be coaxed to lay eggs on halved cantaloupes. I kept this colony going successfully through several generations for over a year, but it was hard work and it finally succumbed to an infestation of mites, a common terminator. The Drosophila (fruitfly or vinegar fly) research field is so increasingly advanced and dominant with its many genetic strains and constructs that few 'fly people' now want to use anything else. Steve (Halifax) ################################################# Quoting Bev Wigney <bev@magickcanoe.com> Thanks for the encouragement with regard to the crane flies. They are fascinating insects. The best on line key and image library that I've come across so far is "The Crane Flies of Pennsylvania" website which was developed by Chen Young on the Carnegie Museum of Natural History portal. There is an excellent photo gallery associated with the site (a few of my photos have been used in the species galleries). There is also a pretty good interactive ID key at this URL: http://iz.carnegiemnh.org/cranefly/idkeys.htm Unfortunately, portions of the site require a good net connection - I'm just using a modem stick, so it's quite clunky for me these days. Interesting about the bristletails and the two flies on volcanic sea cliffs! They seem to have a fascinating natural history. Has anyone checked for them around Delap's Cove trail as that seems as though it might provide similar habitat(?). If I'm over there any time, I shall try to have a look for them. But you're right - these types of cliffs are fairly treacherous to work around. By the way, for those who are a bit curious about what I am doing with these moth, crane fly, beetle, bee, spider and other sightings. My interest has always been on species diversity within a chosen area of study. When I lived in eastern Ontario, our farm was my study area and I went out at least once or twice a day, making the rounds with my camera to observe and photograph insects and spiders as they appeared throughout the season. In the evenings, I would photograph moths attracted to our porch lamp for the short while it was turned on. Repeated observation can reveal much about invertebrate life in a study area - their life cycles, numbers, association with certain plants or other insects, and even behaviour and social interaction - for example, the interesting egg case guarding behaviour of many spiders. Over several seasons, I amassed a collection of several thousand photos of invertebrates, many of which are posted in my pbase galleries. After selling the farm last spring (following the death of my husband in late 2008), I set out to look for a place in Nova Scotia that could serve as an interesting study area from spring through autumn. This place at Round Hill seems ideal - a couple of acres on a brook - with reasonably natural vegetation as the house has been pretty much unoccupied for a decade or so (believe me when I say the house is in quite a state, but that's all part of "the project" I'll be working on!) There are also many nearby natural areas if one were to venture further afield, but really, for the kind of study that I'm interested in (invertebrates), even a large backyard can seem like a vast wildlife reserve, so really little need to go beyond its borders. I'm looking forward to seeing what turns up over the next few months of observation. Bev Wigney Round Hill, N.S. N44.46.23, W065.24.18 (WGS84) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Quoting David & Alison Webster <dwebster@glinx.com>: > Hi Steve, May 29, 2010 > I may be repeating myself re hardiness but can't find any > previous e-mail-- Some crane flies are quite winter-hardy. > > Most of my firewood is stored outdoors either in the woodlot or > in the yard as tiers of wood cut to nominal 15" length, piled ~40" > high with a 'roof' of 22" wide polyethylene on top held in place > with one layer of firewood. Over winter, the upper surface of this > polyethylene is relatively hostile, being not as buffered against > temperature extremes as e.g. soil or litter on soil. > > So when I noticed some cranefly larvae on top of a woodpile in > North Alton one December I was curious to see if they would develop > and moved some to a woodpile top in Kentville; excerpt of > spreadsheet pasted below-- Adults emerged sometime between June 5 > and June 25. > START OF PASTE > Tipula (Platytipula ?) or (Nobilotipula ?) 25-Jun-02 Kentville > Reared from larvae that were moved from North Alton. Collected in > North Alton, Dec 2001 from debris on polyethylene; kept outdoors; > emerged after June 5, 2002; pupal cases in vial; also leg in > envelope; distal veins have a few microtrichia. > END OF PASTE > > With regard to continuous culture, is larval development > controlled by temperature or day length ? > > I guess nothing beats the convenience of rodents (as my wife once > remarked with great indignation 'animals shouldn't be used as > Guinea Pigs'). Why would it not be possible, given a range of > temperature or light conditions, to culture crane flies (e.g. larvae > that live in water, debris or sod) so adults emerged year round ? > > Yt, Dave Webster, Kentville > ----- Original Message ----- From: "Steve Shaw" <srshaw@Dal.Ca> > To: <naturens@chebucto.ns.ca> > Sent: Saturday, May 29, 2010 12:58 AM > Subject: Re: [NatureNS] Moths - Paonias myops and others - added Craneflies > > >> Hi Bev, >> A word of encouragement to say that it would good to have someone >> photographing and identifying tipulids (crane flies) and related >> groups here. It was one of your excellent images from Ontario of a >> small asilid, Dioctria hyalopennis, that helped me ID the same species >> that I had been collecting in the garden here. Identification of >> flies is a problem if you don't like keys (who does?). BugGuide.net >> seems to be the most comprehensive source of images, but is tedious >> work if you don't have even a genus name. >> >> On volcanic sea cliffs facing NW fairly near you (Fundy shore, around >> Halls Harbour and Harbourville particularly), we've collected >> bristletails (Archaeognatha) at about 1-2 metres above high tide line, >> where rain water leaks out of the rotten rock face. The only other >> fairly common insects inhabiting the same seepage spots are two >> species of fly, one a large dolichpodid (Liancalus genualis) that I'm >> also interested in and periodically collect. The other fly appears to >> be a smallish 1 cm long tipulid (though it may be in a related group) >> with fold-back spotted wings and springy legs (it continually does >> springy 'press-ups' with these). The cliffs are high enough in places >> that relatively few spiders and beetles get down to the bottom of the >> cliffs, so while it is a rather barren habitat it's probably >> relatively insect-predator free. These tipulids should be found also >> further down, nearer your area, though I am not familiar with the >> cliffs and their accessibility there. I'd be interested if you can >> track down the ID of this tipulid, if you get out to the cliffs and >> can get photos. You will know already that most of these Minas Basin >> cliffs are dangerous even well before high tide -- look up the local >> tide timetable on the web, to avoid getting cut off. >> >> The harshness of the Fundy cliff area raises the question of how the >> three species survive there through the winter. The bristletails >> solve this by migrating into deep cracks in the cliff face in >> September and not coming out again until at least May. There's a >> small waterfall coming over the cliff round a corner about 1.5 km SW >> from Halls Harbour, and even in November a rock face next to the falls >> has had numbers of 1.5 cm long larvae in among the algae, in the >> running water. These turn out to be larvae of the same tipulid (I >> reared one through to the adult stage). Presumably these larvae leave >> the water flow even later in the year before freeze-up and perhaps >> pupate in rock crevices nearby. Possibly they may also live in the >> more benign environment of the stream above the falls. >> >> Why could Tipulidae be interesting to biologists? The FLYTREE project >> currently fingers that family as closest to the ancestry of all the >> 'higher' flies, the Brachycera. The nervous system in the eye changed >> at the origin of the Brachycera, so what the tipulid-like ancestor had >> before then needs to be investigated more thoroughly. Among people who >> are interested in how brains wire up in development and who like to >> study simplified 'model' systems, this spotlights tipulids. Work >> becomes much easier if the species can be kept continuously in >> culture, but I haven't heard of anyone being able to do this with a >> tipulid. >> Steve >> (Halifax) >> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> Quoting bev wigney <bev@magickcanoe.com>: >>> Thank you, Chris. I've just finished updating the captions with >>> these identifications. One of those Tortricidae moths (the one with >>> the narrow stripes) is my nemesis - I've photographed it or a very >>> similar species several times in Ontario, but haven't come up with >>> an ID to species as yet. >>> If this weather warms up any time soon, I'll continue to add more >>> photos to this gallery and hopefully it can serve as something of a >>> resource for others who may want to do some mothing in the region. >>> Here's the URL again for anyone who is interested in following the >>> moths that I'm seeing - or currently "not seeing" here at Round Hill >>> (just east of Annapolis Royal). >>> http://www.pbase.com/crocodile/round_hill_moths >>> By the way, I am also trying to photograph and ID craneflies if >>> there is anyone who has an interest in those as well. I think I may >>> have been able to ID a couple so far, but don't mind being corrected: >>> Tipula valida >>> http://www.pbase.com/crocodile/image/124870027 >>> http://www.pbase.com/crocodile/image/124870028 >>> Epiphragma fasciapenne >>> http://www.pbase.com/crocodile/image/124870029 >>> I'll add more craneflies to this gallery as I come across them over >>> the season. >>> >>> Bev Wigney >>> Round Hill, N.S. >>> N44.46.23, W065.24.18 (WGS84) >>
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