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--Apple-Mail-1-1000196533 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1; delsp=yes; format=flowed Thanks Chris, Derek, -- very detailed info, but a difficult =20 distinction when you are not familiar with these beetles. It looks like they were C. repanda -- see additions to Chris' reply =20 below. There were dozens of them flying around in sunlight on a rocky-sandy =20 area, so maybe these had just emerged and were engrossed in mating =20 flights? Makes you wonder what the current value of the fancy elytral =20= spots is, if they are not a distinctive species identifier (if we can't =20= tell them apart, presumably the beetles can't either*) and the spots =20 don't much look like camouflage either. Presumably, the two species =20 smell different, at least to a beetle. Or perhaps they have diverged =20= in their habitat preferences or adult emergence dates, so they don't =20 overlap? Is their any suggestion of possible hybridization? Thanks again for the identification info. Steve * the spots could reflect differently, though, in the two species, in =20= the UV that we can't see. On 16-May-08, at 7:47 PM, Christopher Majka wrote: > Hi Steve, > On 16-May-08, at 6:35 PM, Steve Shaw wrote: >> Hi Chris, Angus:=A0=A0=A0while looking for something else, I found a = lot of =20 >> tiger beetles out today on rocks up above the tide line, along the =20= >> shore.=A0=A0=A0Overall brown with some metallic green specks (and = metallic =20 >> green undersides), but under magnification has very distinctive =20 >> creamy markings on elytra, closely matching _Cicindela =20 >> duodecimguttata_ on Bugguide.net.=A0=A0=A0Nothing like Angus' pic.=A0=A0= >> Is _C. duodecimguttata_ a likely or common species in N.S. at this =20= >> date? > > Yes, its one of the commonest species in the region. In this region =20= > differentiating between=A0Cicindela duodecimguttata (the = twelve-spotted =20 > tiger beetle) and Cicindela repanda (bronzed tiger beetle) can be =20 > tricky. > [1] C.=A0duodecimguttata has a narrower pronotum,=A0which=A0is about = as long =20 > as it is wide, whereas in C. repanda the pronotum is distinctly wider =20= > than long. > Looks like repanda based on this. > The constriction at the front of the pronotum of=A0C.=A0duodecimguttata=A0= is =20 > not as deep as the constriction at the back resulting in a =20 > "trapesoidal" shape, whereas the front and back constrictions of the =20= > pronotum of C. repanda are symmetrical. Not sure about this, but the contours on the pronotum looks like the =20 quasi-hexagonal shaping on repanda on the NDSU website Chris mentions =20= below, and less like the squarer contouring of 12guttata. > =A0 > Also in=A0=A0C.=A0duodecimguttata the elytral epipleura (the portion = of the =20 > elytra which is folded over and faces the ground) is pale for most of =20= > its length, whereas in C. repanda it is dark for most of its length =20= > (generally you need to have the specimen in hand to be able to observe = =20 > this). This is very clear, it's definitely very dark all the way along, so =20 again repanda. I had to gas one with CO2 to poke around and see this, =20= otherwise too lively even when fridge-cold. Never met an insect before =20= that took so long to anaesthetize, 1+ minutes. (For readers of =20 delicate sensibility potentially distressed by this seemingly inhumane =20= procedure, CO2 anaesthesia is a common method of knocking out live =20 insects for examination if you actually want them to recover, the basis =20= for which action is not clear and unlike CO2 action on vertebrates. =20 Most insects come round again in a few minutes, and after ~1/4 hour are =20= back to normal). > > Take a look at the following photographs to see the difference in =20 > species. > > http://www.ndsu.nodak.edu/ndsu/beauzay/tigerbeetles/=20 > C_duodecimguttata.jpg > > http://www.ndsu.nodak.edu/ndsu/beauzay/tigerbeetles/C_repanda.jpg > > The degree of maculation on the elytra can vary quite a lot from =20 > individual to individual in both species. Both species are common and =20= > widely distributed in the Maritime Provinces. > > Cheers! > > Chris > > Christopher Majka > Nova Scotia Museum, 1747 Summer St., Halifax, Nova Scotia, Canada=A0 = B3H =20 > 3A6 > c.majka@ns.sympatico.ca --Apple-Mail-1-1000196533 Content-Transfer-Encoding: quoted-printable Content-Type: text/enriched; charset=ISO-8859-1 Thanks Chris, Derek, -- very detailed info, but a difficult distinction when you are not familiar with these beetles. =20 It looks like they were <italic>C. repanda</italic> -- see additions to Chris' reply below. There were dozens of them flying around in sunlight on a rocky-sandy area, so maybe these had just emerged and were engrossed in mating flights? Makes you wonder what the current value of the fancy elytral spots is, if they are not a distinctive species identifier (if we can't tell them apart, presumably the beetles can't either*) and the spots don't much look like camouflage either. Presumably, the two species smell different, at least to a beetle. Or perhaps they have diverged in their habitat preferences or adult emergence dates, so they don't overlap? Is their any suggestion of possible hybridization? Thanks again for the identification info. Steve * the spots could reflect differently, though, in the two species, in the UV that we can't see.=20 =20 On 16-May-08, at 7:47 PM, Christopher Majka wrote: <excerpt>Hi Steve, On 16-May-08, at 6:35 PM, Steve Shaw wrote: <excerpt>Hi Chris, Angus:=A0=A0=A0while looking for something else, I = found a lot of tiger beetles out today on rocks up above the tide line, along the shore.=A0=A0=A0Overall brown with some metallic green specks = (and metallic green undersides), but under magnification has very distinctive creamy markings on elytra, closely matching _Cicindela duodecimguttata_ on Bugguide.net.=A0=A0=A0Nothing like Angus' pic.=A0=A0 Is _C. duodecimguttata_ a likely or common species in N.S. at this date? </excerpt> Yes, its one of the commonest species in the region. In this region differentiating between<italic>=A0Cicindela duodecimguttata</italic> (the twelve-spotted tiger beetle) and <italic>Cicindela repanda</italic> (bronzed tiger beetle) can be tricky. <italic> </italic></excerpt> <excerpt><italic>[1] C.=A0duodecimguttata</italic> has a narrower pronotum,=A0which=A0is about as long as it is wide, whereas in = <italic>C. repanda</italic> the pronotum is distinctly wider than long. = <color><param>FFFF,0140,31DC</param> Looks like <italic>repanda</italic> based on this.</color> </excerpt> <excerpt>The constriction at the front of the pronotum of=A0<italic>C.=A0duodecimguttata=A0</italic>is not as deep as the constriction at the back resulting in a "trapesoidal" shape, whereas the front and back constrictions of the pronotum of<italic> C. repanda</italic> are symmetrical. </excerpt><color><param>FFFF,0140,31DC</param>Not sure about this, but the contours on the pronotum looks like the quasi-hexagonal shaping on <italic>repanda</italic> on the NDSU website Chris mentions below, and less like the squarer contouring of <italic>12guttata</italic>. </color><excerpt>=A0 Also in=A0=A0<italic>C.=A0duodecimguttata</italic> the elytral epipleura (the portion of the elytra which is folded over and faces the ground) is pale for most of its length, whereas in <italic>C. repanda</italic> it is dark for most of its length (generally you need to have the specimen in hand to be able to observe this). </excerpt><color><param>FFFF,0459,34F7</param>This is very clear, it's definitely very dark all the way along, so again <italic>repanda</italic>. I had to gas one with CO2 to poke around and see this, otherwise too lively even when fridge-cold. Never met an insect before that took so long to anaesthetize, 1+ minutes. (For readers of delicate sensibility potentially distressed by this seemingly inhumane procedure, CO2 anaesthesia is a common method of knocking out live insects for examination if you actually want them to recover, the basis for which action is not clear and unlike CO2 action on vertebrates. Most insects come round again in a few minutes, and after ~1/4 hour are back to normal). </color> <excerpt> Take a look at the following photographs to see the difference in species. = <color><param>0000,0000,EEEE</param>http://www.ndsu.nodak.edu/ndsu/beauzay= /tigerbeetles/C_duodecimguttata.jpg</color> = <color><param>0000,0000,EEEE</param>http://www.ndsu.nodak.edu/ndsu/beauzay= /tigerbeetles/C_repanda.jpg</color> The degree of maculation on the elytra can vary quite a lot from individual to individual in both species. Both species are common and widely distributed in the Maritime Provinces. Cheers! Chris Christopher Majka Nova Scotia Museum, 1747 Summer St., Halifax, Nova Scotia, Canada=A0 B3H 3A6 <color><param>0000,0000,EEEE</param>c.majka@ns.sympatico.ca</color> </excerpt> --Apple-Mail-1-1000196533--
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