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.

Tuesday, November 23, 2010

Discus catskillensis : Angular Disc

Here is Discus catskillensis, the Angular Disc. I found this one at Ricketts Glen State Park. In most of my books it's listed as Discus rotundus catskillensis, but apparently it now enjoys full species status. It differs from D. rotundus by the angular periphery and lack of blotches.

As a bonus I got to actually witness this snail lay an egg through my microscope. It happened when I was cleaning out the little petri dish terrariums I've been keeping smaller species in. I looked at the snail and it looked odd, like it's neck was bulging. I placed it under my microscope and, sure enough, I was able to see it push out an egg. This was on Nov. 17 and they (there were 4 total) have not hatched yet.

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

Monday, November 22, 2010

Unknown Valloniidae species

By Sunday I was feeling antsy to get outside. I was sure I was going to get up early and hit Plymouth Flats for migrating waterfowl, gulls, Snow Buntings, and possibly something juicy like a Lapland Longspur. However my flu still had the best of me and I slept in. Eventually by the afternoon I decided I'd take my chances and I'd make my older daughter come with me to do a little hiking around in Frances Slocum State Park.

We didn't stay long but I identified some places that I think will be great for snails come the springtime. Specifically I found some rocky outcrops that I didn't even realize were there when my only focus was on birding.

Checking a couple places I found what I thought was my only snail, a Stenotrema hirsutum (Hairy Slitmouth). I picked it up and put it in a little baggy I had. I also decided to grab a pinch of substrate by it to accompany it on the way home. Fast forward to when I got home and looked at the bag. I noticed a tiny little snail in the dirt.

This snail has a 1.7mm diameter, is umbilicate, obviously has ribs, and has about 3 1/2 whorls. It also has what I think is described as spiral striae (lirate?). The snail itself is mostly colorless but its tentacles are clear with black flecks throughout. I'm fairly sure it is in the family Valloniidae but I'm having trouble getting to species. So I'll talk out my thought process via this blog.

So first things first, I got it to the family basically just because I've had my nose in the books for the past couple months, thumbing through trying to get my bearings. I've paged through looking for other similar families but seem to come up empty.

That brings me to what it could be specifically. Top contenders in my mind seem to be Planogyra asteriscus, Vallonia costata, and Vallonia perspectiva.

Of those three, only one is listed in Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce): Vallonia costata. So it seems like the obvious answer-- after all, I'm a newbie and I doubt I'm finding state records at this level of my knowledge. The one problem is that this snail does not exhibit an expanded lip. Also, it is a little too small. So, perhaps, it is that this is an immature Vallonia costata who needs to grow and develop the telltale lip. But it does mention the spiral striae in Pilsbry.

Planogyra asteriscus measures 1.7 to 2mm and, according to the 1960 Burch key, its range is Maine, Massachusetts, New York, and Michigan. We're an hour away from New York state, so it's a possibility.

Vallonia perspectiva is 2mm or less and its range (again, according to the 1960 Burch key) is New Jersey to Alabama, west to Minnesota, Utah, and Arizona. So, again, it's a possibility, even if not on the state list. It doesn't have that expanded lip.

So that's that. Likely an immature Vallonia costata, maybe something else. I'm going to hold onto it in a petri dish terrarium and see if it grows any and I'll post on this blog any definitive answer.

Monday, November 15, 2010

Neohelix dentifera : Big-tooth Whitelip

On my birthday hike with my older daughter, Emma, to the waterfalls at Ricketts Glen I found this large snail under some leaf litter along the wet cliff-face. I believe it to be Neohelix dentifera, the Big-tooth Whitelip. This snail seems to be close to Neohelix albolabris but is most notably differentiated by the parietal tooth. The common name "Big-tooth Whitelip" rubs me the wrong way as the parietal tooth is so small, but, as this individual measures very low on the recorded diameter size, this is perhaps a younger individual who maybe will earn the "big-tooth" portion of his name. This individual measures a width of 20.7mm and height of 10.3mm.

UPDATE: As you'll notice by the comment to this article, Neohelix albolabris can also have a parietal tooth, so apparently it's not a truly the key difference. Guess I should have read the Pilsbry species account for the similar N. albolabris before reaching my conclusion instead of just using the Burch key. However,  I still think this is probably N. dentifera based on the height of the shell (as also referenced in the comment below). Mathematically it's more depressed than either measurements evidenced in Pilsbry (for N. albolabris or N. dentifera). But, since N. dentifera is the more depressed of the two, I figure it's a good bet.

Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce) with my own county added to range (in orange). Formerly unknown to Luzerne County.

Thursday, November 11, 2010

Xolotrema denotatum : Velvet Wedge

I found this empty shell at Ricketts Glen State Park near the same fallen log that I found the Anguispira alternata. It measures 18.1mm in width. The books list this as 19mm to 25mm but I figure that's close enough. One interesting thing is that I can see what looks like a pupa/chrysalis inside the shell.

Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce) with my own county added to range (in orange). Formerly unknown to Luzerne County.

Wednesday, November 10, 2010

Some Photos From the Leaf Litter

Out, about, and lifting logs I see interesting things. Occasionally I have the wherewithal to snap a photo. Here are a few interesting photos I managed with my point-and-shoot.

Strange Bedfellows

Lifting a piece of bark at Ricketts Glen State Park I found these guys nuzzled up together. I collected the slug but have yet to figure out its definite identity (It's philomycid and has milky white mucus but I'm still trying to find a definitive answer to the mucus colors of these slugs-- I think it barely has the markings of a P. carolinianus but it's hard to tell with it being so heavily mottled). The salamander is likely an Eastern Redback without the red stripe. I just thought it was interesting that these two were found so close.  A month or so previous, when I was just starting out and didn't realize how interested I am in the native slugs, I had found a philomycid with a Spotted Salamander nearby-- but nothing as close as the cuddle these two exhibited! Thinking now I wish I had collected the philomycid I found with the Spotted Salamander to see if, over the years of collection, I can find a connection between which species of philomycids and salamanders are found together.

Bee Hibernating

Last week I was lifting logs and found this sight, a bee apparently hibernating. The interesting thing about this, though, is that after I came home and downloaded the photo I grabbed I noted some larvae on the bee's eye. I wonder if it's feeding on the bee while it remains helpless in its torpid state. Make sure to click on the photo to enlarge and see the larvae.


Here I lifted a piece of plywood in the area where I had found all the Cepaea nemoralis and found this fellow. A quick email to local naturalist Rick Koval proved it to be a Northern Brown Snake.

A Bonus Studio Shot

 This is actually a studio shot. I set up my office to be my macro studio. This Cepaea nemoralis is on a gourd and the background is just my wall color. I thought it made for a cool monochromatic shot.

Tuesday, November 9, 2010

Anguispira alternata : Flamed Tigersnail

I'm fairly sure this is Anguispira alternata, the Flamed Tigersnail. This fellow is pretty dull compared to some of the photos I've seen online but Pilsbry mentions the snail being duller in late seasons. I found this fellow along with a couple of empty Polygyrid shells near a fallen tree at Ricketts Glen State Park (still just barely in my own county). I tried using Pilsbry to get it to subspecies/form but couldn't do it. Maybe down the road when I'm more knowledgeable I'll be able to go back to this guy and accomplish that task.

This specimen has a width of 18.1mm and height of 8.6mm.

Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce) with my own county added to range (in orange). Formerly unknown to Luzerne County.

Monday, November 1, 2010

Zonitoides arboreus : Quick Gloss

This is Zonitoides arboreus, common name Quick Gloss. I found many of these tiny snails at Frances Slocum State Park on the mountain bike path the same day I found my Philomycus togatus. I've just been lazy/busy on making an identification. Actually it's two individuals I found at Ricketts Glenn that have been consuming the time I have to study identification-- and I still haven't id'd them.

Anyhow, click on the photos to enlarge. The two colors are pretty cool-- dark up top, clearish down bottom.

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

Friday, October 29, 2010

Identifying Zoidberg

Well, it's a learning process. It appears my first instinct was correct in the identification of my philomycid slug I affectionately refer to as Zoidberg-- it is a Philomycus togatus (Toga Mantleslug). I have observed the animal for a week or so now and realize that the foot sidewall always has a pinkish orange hue. In the field I guess the lighting made me think it was paler. Also the mucus color of orange is diagnostic as the only known philomycid with orange mucus is the Toga Mantleslug.

I can't find the reference where I read that P. togatus is the only Philomycid known to have orange mucus but I will update this post when I refind that quotation.

From H.L. Fairbanks' The Taxonomic Status of Philomycus Togatus (Pulmonata: Philomycidae): A Morphological and Electrophoretic Comparison with Philomycus Caolinianus (Malacologia, Vol. 27, No1, 1986):

"Among the species of Philomycus only P. rushi Clapp, 1920, a small (15-20mm) slug, has been described as having orange or red in the sides of the foot. Pilsbry (1948) synonymized P. rushi with Palifera ohioensis (Sterki). There are two large Palifera (P. varia and P. ragsdalei) with red or orange in the foot margins. However, Philomycus togatus has a dart sac and dart and therefore must remain in the genus Philomycus. This makes it the only know species in the genus recorded as having orange foot margins."

Interestingly I also now possess a P. carolinensis/ P. flexuolaris and the mucus is a milky white but it's very hard to see a difference in mantle pattern. Both individuals are heavily mottled but with the P. togatus I can make out lateral stripes on both sides. On the other I can just barely make out darker spots of dark brown/black on the back as two close lines leaving me still dumbfounded as to it's identification as either P. carolinensis or P. flexuolaris. If I went based on likelihood of know distribution I'd guess P. flexuolaris, especially since it was collected up here in the mountains in the northeastern portion of our state. Eventually I'll post photos and hopefully a definitive identification.

Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce) with my own county added to range (in orange). Formerly unknown to Luzerne County.

Wednesday, October 20, 2010

A Slug Named Zoidberg

Yesterday after I work I popped over the the mountain bike path side of Frances Slocum to see what I could find. Looking over at a log I found this nice, big Winding Mantleslug (Philomycus flexuolaris) just slugging on by. I grabbed him and he absolutely filled my hand with orange mucus. At first I thought maybe that meant it was a Toga Mantleslug (Philomycus togatus) as I didn't (and still don't) know the mucus color of P. flexuolaris. Ultimately, however, I believe this to be P. flexuolaris based on it's markings. Interestingly, though, I was thrown by the orange because the foot fringe looked pinkish orange when it was irritated and filling my hand with orange mucus, but after it rested the foot fringe went back to a paler color.

Today I brought him home a treat-- a bunch of fungus I collected. After all, as I learned yesterday, Philomycus (and probably the family, Philomycidae) translates to "friend of fungus." This is the name given by either Sterki or Rafinesque (or someone else, can't remember) when they named the genera/family because they eat fungus. I put him down on my photo table, presented him the fungus, and he went right to work.

Immediately upon inspecting him with my hasting triplet I named him Zoidberg. Now, I don't know if there is something inherently wrong with naming something you are going to dissect or preserve (basically murder), but I did it anyway. Look at that mouth, it has those vertical bars like the Futurama character. I pulled away the fungus and could see his full mouth. It looked like a suckerfish, but more sculpture to it.

I should also note that I was going to try to compare him to the first P. flexuolaris I had gotten from Moon Lake Park, but when I pulled out that jar I learned that it had escaped. Apparently I made the air hole way too big and it slid out. So now I must have a big 66mm mantleslug winding around my house. Oh well. Lesson learned: smaller holes.

Monday, October 18, 2010

Ventridens ligera : Globose Dome

Next on my list of identified Luzerne County land snails is Ventridens ligera, commonly known as the Globose Dome. These snails (or at least their shells) were under pretty much every log I lifted along the railroad tracks in West Wyoming near Airport Gravel and Sand.

Using Birch's 1962 key I came to the conclusion of Vitredens demissis (Perforate Dome). However, after reading more about the species on the Carnegie website I changed my mind. First, Vetridens demissis was completely left off his 2006 county distribution list. Second, in the account I learned that juveniles of Vitredens demissis have a basal lamina. After reading that I checked some of the juvenile shells I picked up and found no basal lamina leading me to rethink the identification. What I realized is that I still don't have a good grasp on what would constitute slightly depressed versus globose.

From there I believed it to be either Vitredens interdextus (Pyramid Dome) or Vitredens ligera. I was leaning towards Vitredens ligera, but not totally sure of myself after the misdiagnosis. So I shot an email off to Carnegie Mollusk Curator Tim Pearce to ask a few questions about Ventridens and identification in general.

He pointed out that Ventridens intertextus have a spiral striae (a fact I missed in the key) and that the juveniles have an angular periphery. So the identification was clinched in my mind as Ventridens ligera.


Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce) with my own county added to range (in orange). Formerly unknown to Luzerne County.

Identification notes:
Height: 10mm range
Width: 10mm range
Shell: Narrowly Perforate Heliciform
Lip: Thin, Unreflected
Apertural Teeth: None
Aperture: Ovate-lunate
Whorls: 6
Other: Pedal Groove

Location Found:
Along railroad tracks near Airport Gravel and Sand
West Woming, PA- Luzerne Co.
41.307306097168215, -75.85408061742783

Thursday, October 14, 2010

Known Luzerne County Land Snails

Carnegie Museum Curator Tim Pearce recently recompiled distribution maps of land snail species by county in Pennsylvania. My own county, Luzerne County, was among the least represented with less than 15 known species. So that's exciting in a way as now my information will be pretty valuable. Already I know a couple species that I've found aren't on the map. The pdf of distribution can be found at:

Here is the list of known species in Luzerne County:
Arion subfuscus
Discus catskillensis
Euchemotrema fraternum
Helicodiscus parallelus
Neohelix albolabris
Novisuccinea ovalis
Pallifera dorsalis
Ventridens intertextus
Zonitoides arboreus
Zonitoides nitidus

Tuesday, October 12, 2010

Philomycus flexuolaris: Winding Mantleslug

UPDATE: It seems slugs are not as easy as I assumed. This article could be totally wrong in identification. Unfortunately this fellow escaped his jar due to a too big slit in the aluminum foil cap I had on the jar and so I can't go back and, now a little more knowledgeable, make a definitive identification. So take anything written below with a grain of salt.

Slugs seem to be a little easier to get to species. There are 17 known species in Pennsylvania, most of them non-native. Also it helps that there is a great and current slug key of the known PA slugs on the Carnegie Museum site (

This slug is Philomycus flexuolaris, the Winding Mantleslug. It is a native of Pennsylvania and common in high elevation wooded areas. It is identified to family first by looking at the mantle. This one has the mantle covering the entirety of the back and over the head versus slugs that have a sectioned appearance. After that you can identify by the mottled dorsal line and mottled lateral lines on both sides.

I found this little guy (not that little, this one measures 66mm) under a log at Moon Lake Park while on a walk with my older daughter, Emma, and one of my dogs, Sasha.

Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce) with my own county added to range (in orange). Formerly unknown to Luzerne County.

Identification Notes:
Mantle: Full back and over head
Other: Mottled Dorsal Line and mottled Lateral lines on both sides

Location Found:
Moon Lake Park
Luzerne, Co.
41.25269, -76.055759
Macrohabitat: Mixed Deciduous (mostly oak)
Microhabitat: Under a decaying log used as the side of a path

Monday, October 11, 2010

Cepaea nemoralis: Brown-lipped Snail/Grove Snail

I'm not going to lie that I'm a little disappointed that the first snail I ever noticed/found happens to be a non-native species. Already as a birder I've grown an aversion to non-native species. Still, this is a cool looking snail. I found the original shell at a retention pond area in downtown Wilkes-Barre, PA along some railroad tracks. I was busy looking for sandpipers in the low water of the retention pond. So, once I decided I was into snails, I went back to look for a live specimen. Easily I found a bunch of these snails along the roadside as soon as I parked my car. To be fair, it was drizzling so they were moving about.

Cepaea nemoralis is a common snail of Europe. It goes by the common names Brown-lipped Snail and Grove Snail. It's a good sized snail- the shell I measured is about 21mm high and 20mm wide, give or take.

The most interesting thing while looking for an identification that this snail led me to was an article on thrush selection of banded snails at It seems the polymorphism of these snails (some seem to have more or less bands, yellowish to brownish base colors) helps them survive. Light snails fair better against light dry backgrounds, dark ones against dark backgrounds when it comes to being found and eaten by thrush and other creatures that find the tasty morsel snails by sight.

This is the actual first snail shell I ever collected.
Range map from Land Snails of Limestone Communities and Update of Land Snail Distributions in Pennsylvania (Pearce) with my own county added to range (in orange). Formerly unknown to Luzerne County.

Identification notes:
Height: about 21mm on mine
Width: about 20mm on mine (listed as 22-24mm in Burch)
Shell: Imperforate Heliciform
Lip: Reflected with a brown color
Apertural Teeth: None
Aperture: Ovate-lunate
Whorls: about 5
Other: Color Bands

Location Found:
Epsco Retention Ponds
Wilkes-Barre, PA- Luzerne Co.
41.25508923613776, -75.8547055721283

Amateur To Expert.... Someday

This is the inaugural post for LeafLitterCritters. In this blog I will start from absolutely zero knowledge about land snails (other than the fact I know a snail or slug to see one) and, hopefully, become versed in identification. I'll also occasionally post non-snail terrestrial creatures and whatever of interest I find while out rooting through the leaf litter.

The exposition as to why I've become fixated on land snails comes in two parts. First, while out birding I picked up a rather interesting snail shell and gave it to my daughter, Emma. I didn't identify it or anything, in fact didn't think much about it-- other than I thought it was interesting.

Fast forward to about 6 months later when I was watching PBS and a segment on the episode of 'Nature' centered around the Cuban Painted Snail.  I don't know if you've seen the show 'Nature,' but the cinematography is stunning. And seeing snails the full size of my big screen television-- their scultpure, the eyes at top of their tentacles/stalks-- I was hooked.

It's been about two weeks since I've become fixated on land snails and I already realize one thing-- snail identification is tough. It's not that I don't possess the wherewithal, after all I pride myself on being rather good at sandpiper identification (a tough group of birds), it's that it is hard to find information on snail identification. I can jump on any website and buy a few books on bird identification. Snails, not so much. It took me a week to find a book by John Burch from the 60s entitled: How to Know the Eastern Land Snails. Of course, it's out of date in some ways,  particularly in current taxonomy, but it's a start.

One website I found that is going to be my go-to site is the Carnegie Museum of Natural History's Pennsylvania Land Snail page. I'm lucky to find a page dedicated to the snails in my own state, as there don't seem to be many states that have the same. It's at

But, I digress, and I'm ready to take on the challenge of becoming knowledgeable about land snails.