Very sorry about the unauthorized immigrants Rafael. In USA, they are a favorite toy for children and considered a wonder of summer evening romance in the garden.

Thanks to all, after all is a new Photinus species that is going to be described

Rafael, on which considerations are you thinking that your Photinus - that you firstly mentioned as "American species" - i. e., an exotic invasive one - is a new species? Did you consulted any taxonomist specialized in this group? Otherwise, describing the Iberic population as representative of an undescribed species seems to me very hazardous. Best whishes

I would ask Dr. Kathrin Stanger-Hall for help. Is here on ResearchGate and has just published a work on the Photinus pyralis. He deals mainly with genetic studies but could give suggestions. In private I can send the e-mail.

Answering at Mario Zunino, the catalan specialist has worked together with a mexican firefly specialist and drove to the conclusion that is a Photinus species (which is strictly known from N , C and S America) but is not yet described as still there are some mexican species recently described and others waiting for description.

Thank you Rafael for your exhaustive answer! Being a bogeographer, I'm very curious about any case of "dispersal", mainly through Oceans, so I'll greatly appreciate any information yo will publish about the original range of the N. sp. of Photinus, and about the pocess of its dispersal eastward and reachinc Cataluya, as well as its dispersion within the Iberian Peninsula. Many thanks in advance!

Cheers

Mario

Yes, is a very courious case. The descriptor has arrived to three hypothesis: 1) Some tourists at Mexico (e.g.) enjoyed the Photinus show and got them here to repeat the show at home; 2) A lab working with luciferase has got some specimens to reproduce and then scaped; 3) Some eggs or larvae were carried with the soil with some ornamental plants for gardening

Answering Fernando Angelini I have stopped studying this subject as there is someone else working with it that but I will tell him.

A first paper about the catalan Photinus:

https://ichn.iec.cat/pdf/Butlleti_82_2018/24-2018_Vi%C3%B1olas_et_al.pdf

And now the specific name: Photinus immigrans:

https://sites.google.com/site/unentomologoandaluz/home/revista-gaditana-de-entomologia/revista-gaditana-de-entomologia-volumen-ix-num-1-2018

This is biogeographically highly interesting record. Thank you for sharing!

This species is not only present in the region of Catolonia it seems. More places in Spain have been affected. Let's hope it is not an aggressive invasive species. It has a very nice flashing behaviour though and I am curoius to study it's phylogeny, courtship behaviour and ecology. We are on it. More news soon :) .. let's hope

Very interesting! It's probably nice to have some beautifully flashing fireflies over there now. Most inland territories in Europe lack any nicely flashing fireflies :( There are some Luciola on the Mediterranean coasts though.

Unfortunately, it's not Photinus pyralis - they give one of the nicest displays and at the same time can live on lawns throughout towns (in the Eastern US). E.g.: https://pbs.twimg.com/media/Dg52GIvUcAALVav.jpg, https://bit.ly/2EQ6Be3

It would have been interesting to have DNA sequences (PCR) of luciferase and common genetic markers to get an idea of its relationship to other Photinus.

@Raphaël De Cock @Lynn Faust

"This species is not only present in the region of Catolonia it seems. More places in Spain have been affected. "

Then it looks like it was introduced long ago and had a lot of time to spread to new territories. Maybe decades or even centuries.

Once installed in an area, is quite easy to detect as you see intermitent lights flying in the field. As you can see writing Photinus on youtube (in the United States is a popular attraction).

Rafael Carbonell-Font What is its flying season (months)?

Mid august-mid september

Im still thinking why all the Photinus populations in Catalonia have been found around genetically modified corn crops, and I propose the following hypothesis, based on a secundary effect:

1) A gene to improve the corn is inserted (eg to acquire a resistance against an insect that eats it).

2) In order to check if the new generation of seeds have acquired that resistance the luciferase gene is also implanted, so that genetically modified seeds can be recognized by fluorescence.

3) Next to the gene of the luciferase is the gene of the enzyme that produces the hormone that attracts the Photinus, which is also implanted (by accident).

4) The new corn acquires 3 novelties: insect resistance, fluorescence and hormonal attraction to the Photinus.

Well, I'm not a genetist but think treating with GMOs could have had secundary/colateral effects, so something like this could have happened. What's your opinion?

2) " with GMOs could have had secondary/collateral effects, so something like this could have happened. What's your opinion? "

Even if you are, there can be surprises :)

https://www.youtube.com/watch?v=nhMFxqC89Ac

2) " with GMOs could have had secondary/colateral effects, so something like this could have happened. What's your opinion? "

a) No, this could not have happened. Marketed GMO crops do not have any GFP/luciferase markers or carry-on genes: you then would be turned down by any FDA agency for introducing irrelevant changes. And all GMO crops are thoroughly verified before even any field tests. Further, I don't think Photinus would be attracted to corn in most realistic scenarios.

b) Full specifications of your GMO crops should be publicly available somewhere: you can simply look them up.

3) "Photinus populations in Catalonia have been found around genetically modified corn crops"

One potential scenario is that they were imported with corn from its fields in North America but this seems unlikely because it is the seeds that are imported, not the soil (where firefly larvae could be present).

@Michael Koksharov, nice funny video and thanks for answering, but what the two aquarium animals pictures do represent?

These are young larvae of Photinus pyralis fireflies in the soil.

This are a mystery Photinus, not P. pyralis, and I look forward to hearing more. but I will say in the US where the species P. pyralis is widespread and abundant, some of their showiest displays are indeed over cornfields (they display by the 100s if not 1000s) for some reason. This always surprises me because corn is so very treated with pesticides and or herbicides every step of the way, which should negatively affect the larvae and adults alike and the ground is tilled yearly, but some of the most magificant displays have been over corn. So many mysteries!

Yes, there are a lot of misteries!

.... what do you mean with " they display by the 100s if not 1000s "?

Thanks

Meaning at any given time on peak nights one might see 100s if not 1000s of North American Photinus pyralis flashing over large cornfields in the eastern US. Very beautiful. Hope that helps Rafael, Lynn

Here in Barcelona somebody took some of the legs to DNA barcoding, and they uploaded the results somewhere. So if anybody is interested in study philogenetics ....

In response to Lynn Faust, regarding the attraction of Photinus immigrants for corn, I had come to think whether the transgenic maize could include (by mistake) in its DNA any hormone/substance that could cause attraction to Photinus. The luciferase gene, which is often used as a marker in genetic engineering, could be attached to another gene which would be the one that would codify an attractant substance. I commented this with geneticists, but they told me it was impossible, but who knows ?

Rafael, Depending on which Photinus species, each one prefers to display in certain habits, deep wood after dark, or US P. pyralis prefers open areas at dusk. Usually lawns and fields. I am not certain about the Spanish P. immigrans, but have heard it too likes to fly in open areas. So cornfields create a large flat open space just above the top of the corn, since the mature corn is usually mostly all the same height. The males which congregate loosely, see the flashes of one another, which seems important for their mating display. So, i suspect something similar is occuring with P. immigrans. It is attracted to the cornfields as a nice display arena, and the tall corn provides shade and shelter during the day. Though an intriguing concept, I do not personally believe GMO corn has any bearing on their choice of display area.They probably also flash over yards, fields and gardens, all open areas.

Michael Koksharov what do they eat your captive Photinus pyralis larvae ?

Photinus in general eats earthworms.

@Rafael Carbonell-Font, who did the DNA barcoding and where are those data? Gracies

Rafael Carbonell-Font Earthworms. Apparently, they [Photinus pyralis larvae] don't eat anything else either.

Rafael Carbonell-Font, who did the DNA barcoding and where are those data? Gracies

Michael Koksharov thanks!

Raphaël De Cock sorry for the delay. I sent three males to a Genetic Laboratory in Barcelona (Spain) and they took some legs for Barcoding, but now they are telling me the DNA was not good enough for barcoding (they were kept in dry condition for weeks). Sorry for the bad news :-(

Rafael Carbonell-Font Thanks for this feedback. That is a pity indeed; so now we will have to do that ourselves ... This new species is being reported many times via iNaturalist now - I fear it is expanding in the region, but I also think it is not a problematic invasive sp. i.e. a threat to local fauna or competing with local Lampyridae (most are Lampyrinae branch that predate on snails not earthworms). Best regards

Raphaël De Cock My impression is that many Photinus sp are omnivorous (at least the ones living several hundred km north from the last edge of the Ice age glaciers; there were no earthworms there before the European settlers). Likely, not all of them are complete earthworm specialists. So you might want to check what these really eat.

I will

@Michael Koksharov, we are digging at some spots that are adults of Photinus but never found larvae. Is there any trick to get them ?

The North American Photinus larvae very difficult to find. They are Subterranean in habit, eating small organisms in the soil. I do not think they are only earthworm specialists but I could be wrong. I believe they eat a variety of tiny organisms in the soil. I most often find them right before they come closer to the surface to pupate. But I can never consistently find them if I'm trying to find them. Does that make sense? I usually find them accidentally while doing something else. Sometimes right before pupation you will find them under a dog water bowl or a flower pot or if you are digging something up in your garden among The Roots.

Rafael Carbonell-Font The easiest way is to collect males and females, put them in a box or can with moss and keep for several days. They will likely mate and lay eggs on moss. Then you can wait till they hatch. AFAIK this works well with many firefly species.

Otherwise, they may distribute quite widely (and, maybe, deep) across the soil, so the chances to find them could be small.

One problem is the North American Photinus are extremely difficult to rear from egg to adult. It takes a year so requires quite a bit of dedication. However using Michael's method of pairing a male and a female would be a good approach if you just want to see what the first or second instar looks like. They often die after the first or second instar . Rearing Photinus has been a bit of a Holy Grail in the Firefly World. Some of the other genera are not nearly as difficult to rear. Photinus from egg through the larval instars to adult are difficult! But there is someone out there who will figure it out and hopefully tell the rest of us.

@Lynn Faust, @Michael Koksharov, thanks for your answers :-)