Monday, April 25, 2011

Instead of Looking for Easter Eggs...

I did quite a bit of snailing over the Easter weekend. I am fortunate enough that my home in Dallas, PA is not far from plenty of really great habitat. But, more specifically, I am close to the great old growth forest of Ricketts Glen State Park. As such, I managed to steal a couple  hours both Saturday and Sunday to do a little snailing and birding at the glen.

The first day I really only worked a small patch where the road and the creek combine. While there was 'shit for birds' as I say when there isn't much bird action, there was certainly no lack of terrestrial mollusks.

One snail that I only found in one spot, but 6 individuals, was Euchemotrema fraternum. I interestingly read a couple days ago a reference by F. Wayne Grimm that this is actually a species complex as he wrote here about the species in Ontario.

Euchemotrema fraternum (Say, 1824) - A complex of at least three distinct forms, represented by pure populations and probable hybrids. As there are anatomical, distributional, and habitat differences, it is unwise to subsume them under "fraternum" and look the other way, hoping that a fascinating evolutionary problem will evaporate, leaving identifications simple. In the U.S. known from Minnesota, Iowa, and Missouri eastward across the Great Lakes Basin to Alabama, North Carolina, and New England (Hubricht, 1985). In Ontario, found frequently in mesic forest situations from Algoma and Temagami southward (Oughton, 1948: 9). Breeding experiments and comprehensive anatomical comparisons are to be undertaken when resources and time permit. 

They were all under bark that was laying on the ground within 15 feet of the creek. Alongside them were a couple Discus catskillensis and a immature Polygyrid.

I'm not sure why I didn't take apertural and umbilical views of any of the Discus catskillensis I found, but here is an apical view.

Another snail I found quite a bit of is Triodopsis tridentata. It's probably the polygyrid I find most in my county. 

One interesting individual looks as if he had to overcome some traumatic experience as you can see by the deformity of his body whorl getting close to the aperture and some breaklines:

Another snail I found a couple of is Anguispira alternata. The 'Flaming Tigersnails' that I've noted in the park are definitely not that flaming and instead rather dull compared to a some I've seen as far as the shell goes. But their bodies are very varied with purples and pinks.

I really didn't see many empty shells but had one that struck my fancy:

I haven't had a chance to work a key for it but I'm leaning towards Xolotrema denotatum. However, the ones I've seen in the park are thicker than this shell.  I'll have to revisit these photos at a later date but compare to below... pretty much the same except thickness. Plus this guy is light colored. Some I've seen are dark, hence the name Velvet Wedge.

The next day I found some different species, as well as had some new birds for my year. I had a singing Veery, which seems like it might be a week or so early but I'm terrible with dates and it could be spot on. Also the forest had my first of year Ruby-crowned Kinglets and Blue-headed Vireos.

Speaking of Xolotrema denotatum, I think here's one that seems to have lost his velvety periostracum that gives them the common name, Velvet Wedge:

I only found 2 introduced species, a single Arion subfuscus and a yellow Arion slug. I've seen a couple of these all yellow Arions in the park but am not sure which species it is. The one I found Sunday was immature and crawling on a log right next to a Philomycus flexuolaris.

Almost forgot, on Saturday I also found what I believe are of the Mesomphix genus, maybe Mesomphix perlaevis or inornatus, but I don't have a field microscope to check on the microsculpture, as it's my understanding you can differentiate the two species I mentioned by the presence or absence of minute papillae (see here):

Another snail of interest, this one from Sunday, was a 9mm Ventridens species that I haven't looked at a key to see if I can identify from my photos. But this little guy was just walking around on the leaf litter near one of the falls. Of course he tucked in the second I leaned down to photograph him. But I'd hide too if something way bigger than me was checking me out.

And the flowers were out:

And some mushrooms :

And one last cool thing I saw over the weekend, although this was at Moon Lake State Park which I just went birding and only lifted a couple rocks, finding this creature: a Smooth Green Snake (Liochlorophis vernalis), the first one I've ever seen. But I'm not a herp guy.

WAIT!! How could I forget about the snail I was most excited to find? At least, I'm reasonably sure of identification, I found 3 Haplotrema concavum in various places, but 2 were in close quarters with an Anguispira alternata and Triodopsis tridentata. For those that don't know, Haplotrema concavum is a snail-eating snail, a real killer. These were at Ricketts.

All very cool stuff! How the hell can anyone be bored when there's this much out there? And I'm only scratching the surface...

Wednesday, April 13, 2011

Ventridens ligera lazarus

Although I've been slow to post lately, I've been busily on the snail. Mostly, right now, I've been scouring the drift materials in the creeks close to my rented room in Ithaca. And though it doesn't do much for locality data it does give me a bumper crop to explore and identify.

Another thing I wanted to do was to start really getting into dissecting so that, when in doubt (*cough succineidae cough*) I could pull out the scalpel, pins, and probe and get to the bottom of things. With that in mind on Monday morning before I left for work (~7am) I dropped a Ventridens ligera (Globose Dome) into a jar of water completely without air bubbles. I went about my day, birding, work, gym, etc and about 10pm I got around to pulling him out for dissection. Sure enough I threw him down in a dissecting tray, walked away for a couple minutes and came back to him right side up. A poke and he was retracted into his shell. Stymied!

I dropped him back in water (so this is about 10:30pm on Monday). Tuesday came and went and I couldn't find time to dissect. Fast forward to a few minutes ago (Wednesday at 10pm) and I looked at the jar, saw the snail really lost most of his color, and figured he had expired. Again I pulled on my gloves and readied my makeshift laboratory (I hope the woman I rent my room from isn't reading my blog because I'm sure snail dissection isn't tops on the list of things she'd like me to be doing in this big manicured house I rent a room in). I placed him on the tray and, sure enough, he retracted in. Curious, I put him under the microscope and could see that he was respirating. This means my little Ventridens ligera (lazarus as a cute  play-- I know he didn't die and come back to life, but I had assumed him dead at one point) had been submerged without oxygen for about 48 hours and has not expired. Seems like a fairly long time to be without oxygen. Me, I tend to not go more than 30 seconds at at time without it. Less if I can help it. One of the many reasons I don't swim: I heart oxygen. But apparently little Lazarus doesn't have fully the same feelings, though I'm sure he'd prefer oxygen to a slow watery death if he could communicate.

Interestingly I collected this little fellow along a railroad track that lies in a definite floodplain. It's a little setback from the Susquehanna River-- too far for the river proper to get to, even in the days before the dike, but the creek systems that pour from the mountains to the river to pass right in the spot and the area is very prone to flooding, particularly in spring. In fact, the road that is right next to this area is often closed due to flooding and on either side of the tracks are pools of water that remain year round and overflow during these periods of flood. Along the tracks I found these snails in abundance alongside an unidentified small succineidae species. Mostly they resided under woody and leafy debris. 

Part of me wanted to see if I left the snail out if he would be able to recover but I dropped him back in water to dissect another day.