Wednesday, December 29, 2010

Seeking info

If anyone who reads or happens on this blog I'm putting out notice that I'm seeking a pdf or photocopy of the following:

Patterson, C. M. 1971. Taxonomic studies of the land snail family Succineidae. Malacological Review, 4: 131-202.

Hubrricht's 1958 taxonomic description of Triodopsis picea 

UPDATE: Vagvolgi lumps Triodopsis picea and Triodopsis fraudulenta fraudulenta (or Triodopsis tridenta fraudulenta) together into Triodopsis fraudulenta in his 1968 Systematics and evolution of the genus Triodopsis so maybe there is no real Triodopsis picea... I don't know.

Sunday, December 26, 2010

Zonitoides nitidus : Black Gloss

This snail is Zonitoides nitidus, common name Black Gloss. I found truckloads of these individuals at Kirby Park. According to Pilsbry:

This species is common and generally distributed in the Canadian Zone, more local, though abundant when found, in the Northern part of the Alleghanian fauna, Transition Zone... Z. nitidus is generally found near water or in marshy places, never in upland woods where Z. arboreus lives. In late autumn they sometimes occur in great numbers under dead wood in wet places, where they have assembled for hibernation.

That generally describes my area here in Northeastern Pennsylvania and where I found them: in the Susquehanna River floodplain. Also when I found these individuals-- late September through October.

The animal is a dark blue-gray and has pinkish flecks, most abundant on its sole, less so elsewhere. Another interesting characteristic is that through the shell- near the aperture- you can see an orange-ish organ which I thought to be maybe a heart, but apparently is a lung. This must be what Pilsbry means by "Lung: aerating surface deeply pigmented." Click on the photo to enlarge and see what I mean.

This snail, like its close relative Z. arboreus, is in the family Gastrodontidae, but the genera is named to harken to the family which these snails can resemble, Zonitidae. In fact, at first I believed these snails to be of the introduced genera Oxychilus, mostly because Kirby Park is a former garden which could have easily transported introduced species. In fact, the most abundant land mollusk I've noted in the park is Deroceras reticulum, an introduced slug of the Agriolimidae family.

The measurements of this individual photographed are:
Width: 6.35mm
Height: 2.95mm
Umbilicus: Umbilicate, 1.2mm, Can see all the way to the last whorl
Shell: Somewhat transparent, about 5 whorls, amber tinted
Body: Dark blue-gray (slate) with pinkish flecks mostly at sole. Eyes are short and stout.

Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce)

Wednesday, December 15, 2010


Definitely my Triodopsis is Triodopsis tridentata.  I have to find time to update this blog with many new photos and thoughts on snails. But I'm not because I'm working on an awesome snail iPhone app to help me with identifications. For now I'm only going to create a database with the known PA snails. But eventually I'd like to add all eastern snails, then all North America. It's pretty awesome. It also will double as a specimen log. It'll take a while, however, to research the database. The app doesn't really get me to an identification, but narrows it down as much as possible based on some key elements.

Here's a screen shot of the app:

Thursday, December 9, 2010

My lob not a lob?

I have to find time to post my photos of it, but I was all excited about how easy I believed it was for the identification of Triodopsis tridentata. However, just now while googling around I found a photo labeled Triodopsis tridentata taken and labeled by Dr. John Burch (whose books I've been pouring through) and his animal is tan in color while mine is dark blue. The photo is here: So now the question is, can it be the same and just different colors? I need about 10 more hours in a day to take on this hobby! Hopefully I can post some photos tonight.

Friday, December 3, 2010

Still Trying to Solve my Micro Snail

A couple posts back I believed I had a Valloniidae species. A little more research brought me to where I think I found the true identity. The photo shows my snail sized to match the one I found on the Land Snails of Wisconsin website. Ladies and gentleman, I believe it is an immature Striatura exigua, common name: Ribbed Striate.

Okay, it doesn't have as many whorls, but that's where I think it could be immature. Striatura exigua is supposed to have a 2.3mm diameter, while, as I mentioned in the Valloniidae post, this snail's diameter is 1.7mm.

I'll post more later as I continue to research but most of my time right now is focused on getting the next version of my iphone app, birdcountr, ready for sale.