Intersting P.dorsata

[Will Milne 0]

Hi

 

Was out collecting on one of my local rivers and came across a lovely section of riffle/pool lined with dull orange stained rock/rubble/gravel. Probably not new to anyone else but me , but I was surprised that the P.dorsata or maybe P.pictetti nymphs were so heavily stained a lovely matching color, especially the gills. Wonder what other color variations there are to be found:) The quest begins.

 

 

 

Will

[flytyerboy95 0]

cool stonefly

 

[rockworm 0]

Will

 

Great photo! How big was the nymph? It looks a bit immature. I will certainly be using this photo as the model for some flies.

 

 

 

 

[Will Milne 0]

Glad you enjoyed the image- that one was approx 1 and 1/4 " long so yep a youngun.

 

Will

[Ethan Bright 0]

I would bet that this nymph was in a stream that had a considerable amount of groundwater. Groundwater contained in the aquifer is anaerobic, and thus dissolved iron (Fe+2) is in the reduced form. As groundwater is released in an unrestrained environment, it's oxidized, either through contact directly with dissolved oxygen, or through its use by bacteria that utilize the reduced iron for metabolism. Oxidized iron then shows up as flaky reddish or orange particulates.

 

Cheers, Ethan

[HobbesFly 0]

That's an awesome looking bug. Great pic.

[Tybugs1 0]

Hi

 

Was out collecting on one of my local rivers and came across a lovely section of riffle/pool lined with dull orange stained rock/rubble/gravel. Probably not new to anyone else but me , but I was surprised that the P.dorsata or maybe P.pictetti nymphs were so heavily stained a lovely matching color, especially the gills. Wonder what other color variations there are to be found:) The quest begins.

 

 

 

Will

 

Hi Will

 

Awesome shot ! Miss seeing you on the Photograph forum.

 

Lynn

[Futzer 0]

Will, excellent photo, and Ethan thanks for the information. Hope you both post often.

 

Cheers, Futzer

 

I would bet that this nymph was in a stream that had a considerable amount of groundwater. Groundwater contained in the aquifer is anaerobic, and thus dissolved iron (Fe+2) is in the reduced form. As groundwater is released in an unrestrained environment, it's oxidized, either through contact directly with dissolved oxygen, or through its use by bacteria that utilize the reduced iron for metabolism. Oxidized iron then shows up as flaky reddish or orange particulates.

 

Cheers, Ethan

 

[DHise 0]

Will, excellent photo, and Ethan thanks for the information. Hope you both post often.

 

Cheers, Futzer

 

I would bet that this nymph was in a stream that had a considerable amount of groundwater. Groundwater contained in the aquifer is anaerobic, and thus dissolved iron (Fe+2) is in the reduced form. As groundwater is released in an unrestrained environment, it's oxidized, either through contact directly with dissolved oxygen, or through its use by bacteria that utilize the reduced iron for metabolism. Oxidized iron then shows up as flaky reddish or orange particulates.

 

Cheers, Ethan

 

 

Yes, some of the bottom at Christmas Island has areas with the oxidized iron. Copper, bronze, rust, and orange colored flies worked best in these areas.

[Isonychia 0]

We see a similar phenomenon in the coal-mining areas of West Virginia, where iron from pyrite breaks down and forms "yellowboy" deposits on stream bottoms.

 

John