oh that hurts.
I was one year old when that was originally photographed apparently
Well, I wasn’t that young. But it was my first published note in a biological journal so, minor though it was, it had some significance personally.
Dendrolagus bennettianus Bennett’s Tree Kangaroo would have to be pretty up there as one of the rarest mammals I’ve seen. Their range is only around a 70km long stretch of subcoastal forest.
I think I might have seen a California condor once, but I was young, so I can’t remember.
While I was out for mycoblitz two years ago, I stumbled across these ghost pipes!
While not incredibly rare, I thought it was cool that I found a weird plant on accident. Definitely one of my rarest finds, but probably not the rarest.
As of yesterday, or I guess march 2024 its this moth I saw in Honduras
This (tentative) ID of Hesperus stehri from 2018 is among my rarest observations, with 8 total records on iNat. Although there aren’t many records on iNat, I didn’t have to look far to find it - I found it on the floor of my car!
Others include:
- Chlaenius platyderus (12 total records, second in state, RG)
- Aporus niger (19 total records, first in state, RG)
Two unconfirmed fly observations from a productive trip to Colorado in 2020:
- Thereva albopilosa (2 total records! Needs ID)
- Lasiopogon polensis (4 total records! Needs ID)
Things I’m the only observer for on iNaturalist
Xylophilostenus octophyllus
Cillibus ovalis
Heteromeringia hypoleuca
Eristalopsis wrightae
Ecnomophlebia argyrospila
Probably my rarest for birds given the location I saw it: https://www.inaturalist.org/observations/137396637
Rarest animal I’ve ever seen was actually about 14 years ago. I was fishing on the Missouri River and managed to accidentally catch a 3ft long Pallid Sturgeon (Scaphirhynchus albus). They’re an endangered species and I was 17 at the time, had never even seen a picture of a sturgeon before so it weirded me out with its extendable mouth. I immediately released it, bc I always do catch-release fishing, only for an older fisherman to come SPRINTING from out of nowhere to gush at me about it lol. I was very surprised to find out the weird fish I caught was so important.
This weedy looking thing is the Harringey Knotweed - more specifically, that exact plant is the type specimen, so the Harringey knotweed:
HOLOTYPUS: Overgrown railway marshalling yard at Haringey (Railway Fields), Middlesex, v.c.21, map reference TQ317882. 2 October 1987 1. P. Bailey & D. Bevan. (LTR)
It’s a hybrid of Reynoutria japonica (Japanese knotweed) and Fallopia baldschuanica, the Russian-vine. Whilst seed-embryos of it are surprisingly common where the parents meet, they rarely actually germinate. It’s been found in Belgium twice, and Britain a couple of times.
It’s so rare, that despite both it’s parents being invasive in Great Britain (one being one of the worst invasives here, the other one mostly only when it’s dumped garden waste), that single plant is being actively conserved - seriously, one document says they’ve been trying to clear bramble and ivy from around it!
Rarest animal I’ve seen was in 2002 in Danum Valley Sabah Borneo. I saw a Bornean Bristlehead. These days the internet has photos but back then you couldn’t even find a public available photo of one online. Our guide was saying “you’re so lucky. I’ve had people come here from the US and Europe just to search for this bird and never see one. I only had a compact camera at the time and it was way up in a tree but clear views.
Orcutt grasses from vernal pools in California.
These critters live transient lives in transient pools that fill up with water for only a short time period.
It was a big moment for me this weekend.
I got see a Eastern Massasauga for the first time ever. What made it even better was the sighting was a pile of babies hanging near their nursery den:
An Ouachita studfish, 52nd observation on INat! And a new one for me too, not that I pay that much attention to fish 
Mine is this Fisk’s House Snake that my (now) wife found.
We were both studying in South Africa at the time (it’s where we met), and she was helping me out with my field research, searching for Leopard Tortoises in the Karoo. We were walking transects across the study area with a local undergraduate student. My wife alerted us to a snake. We go over to her to check it out, and it’s one of the most beautiful snakes I have ever seen.
Given that both of us are not from South Africa, and the undergraduate didn’t know what it was, we did the sensible thing and simply took photos. We didn’t want to risk handling or annoying something if it could potentially be dangerous. I also didn’t have my ID guides with me, which were all back in the research vehicle.
Fast forward an hour or so later when we are back to the vehicle, I immediately start flicking through the ‘A Complete Guide to the Snakes of Southern Africa’ book by Johan Marais. This book details information about 150+ snake species in southern Africa. I eventually find the page of a snake that matches my photos - Fisk’s House Snake.
The first thing I notice is that it is listed as Harmless. Damn, I could have handled it no problem!
The second thing I notice as I am reading the accounts is this sentence: “An extremely rare snake that is known from fewer than 20 individuals”. The three of us went wild.
I contacted some herpetologists that I knew, and they said that I should refrain from revealing the exact location to anyone, as these are highly sought after in the illegal pet trade. Others told me that this could be one of a limited number of individuals to be found in their natural habitat. Most are usually found dead on roads. They are also usually a nocturnal species, so what this one was doing out in the morning sun remains a mystery.
Indeed, iNaturalist currently only has 5 observations (with four of those - including mine - coming after the publishing of the aforementioned book).
While not as rare as some observations here, I was lucky enough to see two separate Short-tailed Albatross on my first and only pelagic.
https://www.inaturalist.org/observations/90693791
https://www.inaturalist.org/observations/192759044
Also, this species is more cryptic than rare, but I added the first observation of this tiny ichneumonid species (Orthocentrus asper) to inat a few years ago.
Sandalus petrophya, an uncommon cedar beetle with only 39 RG obs.