May 19, 2024

New project: fern associates

I've just created a new project to collect observations of things that feed on ferns, and all are welcome to join!

It may seem like not much eats ferns, but many insects and other animals do, either casually or exclusively--including sawfly larvae, moth caterpillars, agromyzid and anthomyiid fly larvae, leafhoppers, foliar nematodes, deer, moose, humans, and rust fungi, to name a few. I'm always interested to see something new nibbling on a fern, and in particular I would love to solve the mystery of who is leaving this distinctive pattern on interrupted and sensitive ferns just after they unfurl in the spring:
This is something I've been noticing for a few years now, and I have yet to catch the culprit in the act!

Posted on May 19, 2024 12:33 PM by ceiseman ceiseman | 0 comments | Leave a comment

July 02, 2023

Taking a break!

Hi everybody,

I've managed to keep up with the Leafminers of North America project through the end of June, but I will have very limited computer access between now and mid-August, so there is no point in tagging me on anything until then. It also (as always) will help me tremendously in trying to catch up on the backlog if people make an effort to ID observations (their own or others') before I get to them--it's really helpful to just be able to click "agree"! If you want to try identifying leafminers but don't know how to go about it, you can get my e-book here.

If you have something urgent you want to reach me about--like rearing advice (beyond what's on my website) or questions about what to do with specimens you've managed to rear, the best way to reach me is by email; I'll also check iNaturalist messages when I can.

Thanks, and I look forward to seeing what you all find this summer!


Posted on July 02, 2023 06:12 PM by ceiseman ceiseman | 0 comments | Leave a comment

June 12, 2022

iNaturalist needs a "species group" rank

I have a finite number of minutes in my life, and I've spent far too many of them discussing species complexes vs. species groups with other iNat users. The latest of these discussions is here, and I'm determined that it will be my last. So here's the deal:

A species group is a group of related species that has been defined and named in the literature. It is a useful grouping when a genus (or subgenus) is very large and when there are cases where insects (or their leaf mines, etc.) can be identified as belonging to that group but cannot be identified to species. It is also useful when there are undescribed species that are known to belong to particular species groups; once, for instance, the undescribed birch leafminer in the Stigmella lemniscella group is given a name, I will be able to go through the observations identified as belonging to that group and update their IDs. Going through the thousands of Stigmella observations to look for them would be prohibitively time-consuming.

"Species complex" is typically used to refer to a taxonomically confusing situation where there are multiple biological species going under the same name, and it has not yet been worked out how many species are involved or how to distinguish them. Or this may be known but for practical purposes it is impossible to tell them apart. There can be species complexes within species groups.

iNaturalist does not currently have a "species group" rank, and so to create this grouping, I (and others) have been using the "complex" rank for species groups, adding the word "group" to the name to clarify that it represents a species group and not a species complex. Some people are bothered by this, and go around flagging all of these species groups, saying that the names are malformed. I don't like it either, but it's the best solution I can come up with as long as there is not an option to create a species group. So please vote for this feature request, and then we can all stop wasting our time arguing about this!

Posted on June 12, 2022 05:55 PM by ceiseman ceiseman | 0 comments | Leave a comment

June 22, 2020

Leafminer webinar, June 24

Here's a link to register for a free leafminer webinar I'm presenting on Wednesday evening:

Posted on June 22, 2020 01:36 PM by ceiseman ceiseman | 0 comments | Leave a comment

February 21, 2019

Galls of North America project

Just a quick note to let folks know I've created a Galls of North America project...
...along with an umbrella project to keep track of all the existing regional gall projects...
...mirroring the Leafminers of North America project (, which has a corresponding umbrella project at

I'm not really focusing on galls right now, but it seemed like there was a need for this, since gall inducers (like leafminers) are spread over numerous taxonomic groups, and it's nice to have a centralized place to go looking for gall mysteries to solve.

Please spread the word as you see fit! @srall @susanhewitt @psyllidhipster @gwark @apgarm @edanko @harsiparker @catherineklatt @berkshirenaturalist @jasondombroskie

Posted on February 21, 2019 02:36 PM by ceiseman ceiseman | 2 comments | Leave a comment