European Cynipini in North America

To date, 3 species of cynipini native to Europe have been reported in North America, all on Quercus robur:

Neuroterus anthracinus (agamic): BC, WA, OR, QC, ON
Neuroterus anthracinus (sexgen): BC

Neuroterus quercusbaccarum (agamic): QC
Neuroterus albipes (agamic): QC

Of those, only Neuroterus anthracinus on the west coast has been confirmed by multiple recent records. Ideally, these are the questions I'd like to answer:

Do these species all still occur in NA? If so, where are the limits of their range? We'd start by checking planted/feral Quercus robur trees near the known sites and moving outward. Just photographing the galls and the host tree would be sufficient for this.

Can we close the life cycle for each? These are known from Europe so it shouldn't be hard to find them.

What other species might be present on Quercus robur?

Can we confirm these genetically? That could be done by cutting out larvae and shipping them for sequencing.

Can we confirm them anatomically? That requires obtaining adult inducers (ideally of both generations) from each species present. This will mean collecting and rearing many galls.

What parasitoids and inquilines are found on these galls? Did they bring some with them from Europe, or have any native ones moved to take advantage of them, or did they "escape" their enemies? This may be something we can achieve by sequencing larvae as well, but ideally we would collect and rear many galls to study this.

I'm hoping to recruit people to take the lead on filling in some of these gaps. I'm going to tag those who have observed the galls or other observers in the areas and ask you to either return to these sites to make additional observations or try to point me to local observers who can do so in your stead. Feel free to contribute as much or as little as you'd like.

Given the nature of the question, I think it's likely we can find funding from the Canadian government or potentially from other labs to cover some of the costs of materials and shipping, but I can't promise that yet.

@krisskinou is the only one who has reported quercusbaccarum or albipes on the continent. Those observations were made on a Quercus robur in Papineauville, where @jonathan_mack @cramnaejvallieres and @cecropiabmantis are top observers. I suspect these are also found throughout Quebec as well but I can't be sure.

For both species, the agamic galls appear on the lower side of the leaves in the late summer and early fall; the sexual generation can be found on flowers and young leaves in the spring. See:


For Neuroterus anthracinus, @adam1420 and @krisskinou are the only observers in eastern NA. It is almost certainly found across Ontario and Quebec by now, on urban Q robur. Possibly in the US as well.

The two generations of N anthracinus can be seen here:

More generally, @nsouc @mossy_stone @mhking @donaldasutherland @nikolett6ttn @mws @richardlbaxter may be in a good position to check for these as experienced cynipini observers in Ontario, along with @leoguy in Quebec.

In the western part of NA, @earley_bird @skesau @bastefanidis @kurtsteinbach @brnhn have all reported N anthracinus repeatedly. If you have trees you can conveniently track and sample from, we'd love to have you do that. It's possible there are other species present in the northwest as well.

Thank you all for your time and attention! At this point I'm just making the suggestion and gauging interest; I can add more specific info on rearing and collecting as we move forward.

Posted on Ιούλιος 16, 2023 0736 ΜΜ by megachile megachile


I see at least two trees on the inat map in downtown ottawa that I potentially can periodically check on weekends? I might find some other trees nearby as well if I know what to look for.
I'd be happy to document/collect/bag/rear anything as needed if I find anything.

Αναρτήθηκε από nsouc περίπου 1 χρόνος πριν

I've been checking English Oak for more N anthracinus since first finding them but so far only found two instances in my neighborhood. I'll e happy to keep looking though since it's of interested to you. Since I found these multiple years I think it's likely they are established but going under the radar.

I went out just now and checked the trees around me, I found 1 tree with evidence of the sheath that the galls are in before falling, but no active galls on it. I'll collect any I find for you though.

Αναρτήθηκε από brnhn σχεδόν 1 χρόνος πριν

Sounds good Adam. I’ll ramp up my rearing in the west. I didn’t have much luck rearing last year so I’ll have to fiddle with my methods a bit. @chrisearley should be able to do some collections in Ontario as well, he’s reared Diplolepis galls for me in the past.

Αναρτήθηκε από earley_bird 12 μήνες πριν

Some news on N. anthracinus from some recent time in the main Ento collections in BC...

I've found 3 instances of N. anthracinus in the BC collections, 1 in the Royal BC Museum (5 oyster galls with 5 reared inducers) and 2 in the Pacific Forestry Centre's Entomology collection (2 leaves with galls and 2 reared Synergus). These records are from 1981 in Victoria (RBCM), 1987 in Victoria (PFC), and 1997 in Vancouver (PFC). The 1987 record's data sheet says that the population level was "high" on the Q. robur at the site. I've also been in contact with the Canadian National Collection of Insects, Arachnids, and Nematodes and they don't have any specimens identified to N. anthracinus (or synonyms) from North America in their 10-20,000 specimen Cynipoid collection that is not digitized.

Compared to the North American data available online (one historical 2008 iNat record from Papineauville QC, one 2009 GenBank record from Guelph ON, one 2010 BugGuide record from Toronto ON, and 120 iNat records since 2021), the collections data show that N. anthracinus has been in western North America on Q. robur for quite some time and has been associated with Synergus inquilines for much of that time.

Has anyone else been looking in North American collections for misidentified specimens (or correctly identified but un-digitized specimens)?

Αναρτήθηκε από earley_bird 6 μήνες πριν

Προσθήκη σχόλιου

Συνδεθείτε ή Εγγραφή για να προσθέσετε σχόλια