Tag Archives: florida

Drymaeus dormani

Bill Frank was kind enough to send me some photos of Drymaeus dormani (W.G. Binney, 1857) from near Jacksonville, Florida.

His story in text is “…I then drove down to International Golf Parkway (AKA Nine Mile Road) to go into Twelve Mile Swamp and look for Drymaeus dormani. During my last four or five trips there I was unable to find any Drymaeus at all (living or dead). Again today it looked like I was going to get skunked but finally spotted a  decent sized live Drymaeus on a palm frond about ten feet above the ground. I tried getting it with my rake but there was no hope. I went back to the car and got my twelve foot long net and scooped it out of the tree. Ever since the last hurricane hit, which devastated Twelve Mile Swamp, Drymaeus are nearly impossible to find there. After the hurricane they cut the palm/palmetto way back from the road and since that time have periodically come back to make sure they stay trimmed back. I’m sure that there are plenty of Drymaeus in the swamp away from the road but I’m not brave enough to look just wearing shorts and tennis shoes knowing that there are venomous snakes. It’s dangerous enough just walking along the road looking for snails with cars speeding by just a few feet away – never mind the snakes that come out of the swamp to lay in the swale. Ever since I stepped on a Pygmy Rattlesnake there a few years back I’m a lot more careful than I formerly was.

Today’s Drymaeus is a real basket case having a pitiful looking shell and a lost eyestalk which appears to be regenerating. A real veteran”.

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Liguus book

Just received the new book on the genus Liguus by González et al. A contribution that put some weight (3.4 kg to be precise) and size (4 cm on your bookshelves) to the subject.

Gonzalez 2018 Liguus_Title

Leafing through the book with much attention I noticed the following which will also form my review:

This book is the third book on land snails of the first author and the second one which is confined to one genus, the previous books entirely confined to Cuban species. For this book on the Orthalicidae tree snail genus Liguus distributed from Hispaniola to Florida, Adrián González joined forces with Pete Krull and Luiz Lajonchere; the latter has published on this genus before. The book has 10 chapters on historical studies, collections, palaeogeography, taxonomy of the Cuban, Floridan respectively Hispaniolan (sub)species and colour forms, biology and ecology, and finally conservation issues. On the enclosed CD appendices to several chapters and the bibliography is found. There are 161 (unnumbered) plates of Liguus colour forms and hundreds of colour photos of live snails. 

Liguus tree snails have catched the eye of shell collectors and artists since the beginning of the 17th century till today. They have many different colour patterns and hybridisation between several colour forms does occur, as well as gigantism and dwarfism. The result is an astonishing number of names for them, either officially or unofficially introduced which can be found in both museum and private collections. The book starts with a disclaimer “not deemed to be valid for the purpose of formal taxonomic nomenclature”. Although this seems a justified action, it is perhaps also a too modest action once one realises that 161 names are available for Liguus taxa (Appendix 11), plus several unofficial varieties and a bunch of manuscript names. The authors have neatly streamlined this horrendous chaos into five species (including Liguus flamellus and L. blainianus; if the biological species concept is applied only three remain: Liguus fasciatus, L. virgineus, L. vittatus). The core of the book is thus the two taxonomic parts (Chapters 4 and 5: pp. 63-279 for Cuban taxa, and Chapters 7 and 8: pp. 304-421 for respectively Floridan and Hispaniolan taxa), in which the species, their subspecies and lineages are treated by giving for each the original publication, the type locality, the description, their distribution and concluded by remarks. Especially the many Cuban taxa have not always been properly figured, and the authors have done much effort to search for these specimens and photograph them to modern standards. Almost each is beautifully illustrated on the plates which show 24 shells each, grouped in four rows. On several pages (pp. 73-74, 132, 198, 265, 304, 345, 411-412) maps are given that help to understand how the subspecies and lineages are distributed. Several interspersed plates illustrate the living specimens of one or more morphs.

Gonzalez 2018 Liguus_Shells

Gonzalez 2018 Liguus_Maps

The introductory chapters 2 and 3 present historical data, including iconography and collecting information. Many historical photos are included, and I spotted some that I have not seen before. A brief chapter 4 presents the geological background needed to understand current distribution. Chapter 6 bridges both taxonomical parts and treats a question that several scientists have been struggling with: the connection between Cuban and Florida Liguus taxa. Although many unanswered questions remain, the authors suggest that Liguus baby shells were carried on the wind of hurricanes from Cuba to Florida. They also suggested that these were relatively recent (geologically speaking) events. Of course, these and other questions needs further confirmation and future molecular studies may hopefully at least partially solve them. The final two chapters (9 and 10) are devoted to the biology, ecology and conservation of these snails. In the first one data are compiled among others about life span, population density, predation, host plants and trees. The last chapter treats habitat destruction, introduced predators, protection regulations and laws, protected areas and some suggestions for further conservation.

Gonzalez 2018 Liguus_Appendices

The appendices have been stored on an accompanying CD, which when I inserted it in my system appeared to contain one rar-file. After decompressing a pdf-file of similar size was shown, which raises the question why it was compressed anyway. The file has several appendices showing supplementary information, e.g., historical collecting field trips by U.S.A. malacologists to Cuba, the dispute of the holotype and ‘type’ locality of Liguus fasciatus, collectors mentioned on labels of Cuban Liguus shells, manuscript names and their current status, a list of available names, and additional ecological, anatomical, and conservation data. Together these form the first 58 pages. The final 30 pages are bibliographical references, a huge list in small print.

The authors justified write in the introduction “there has never been of book about Liguus that included every named form from the Cuban archipelago, peninsular Florida, and the island of Hispaniola”. In fact they have made a revision of the genus which is easily readable for non-scientists and, together with the many high-quality photographs, have done an amazing job. Are there no critical remarks to be made? Yes, but only a few. The plates are unnumbered and therefore no link is made between the text and the illustrations. Also no index has been provided which would  have helped to locate easily both the scientific names and person names in the book and appendices. Both points make the book less useful as a reference work. While the authors say “word can fly but writings remain” (p. 497), they would have done better to replace the CD (soon outdated) with a more permanent alternative; the information in the appendices is too important to have it not available.

My overall impression is that this work will be seen as a hallmark for the decades to come. The book will serve both amateurs and professionals and should not be lacking in any relevant library. 

Reference:
González-Guillén, A., Krull, F. & Lajonchere-Ponce de Leon, L.A., 2018. Liguus. The flamboyant tree snails: 1-498 + 88 pages on accompanying CD. F. Krull, 132 1st ST. E #105, Tierra Verde, FL 33715, U.S.A. ISBN 978 0 9847140 5 6. Price US $ 189.90 net (hardcover).

Miocene fossils from Florida

Auffenberg et al. (2015) just released a new paper on fossils from the Miocene in Florida. The land shells fossils have hitherto been considered as Odontostomidae, which as extant species occur in the southern part of South America. Consequently, some ‘mental flexibility’ was needed to explain the biogeography of these fossils.

“Orthalicoid terrestrial snails recorded from the lower Miocene portion of the upper Oligocene to lower Miocene Tampa Member of the Arcadia Formation (Hawthorn Group) of southern Florida and the lower Miocene St. Marks Formation of northern Florida are reviewed. These taxa, previously allocated to the genus Hyperaulax Pilsbry, 1897 (Odontostomidae), are reassigned to Tocobaga new genus (Bulimulidae) on the basis of a distinctive suite of morphological characters, particularly those of the peristome and the embryonic whorl sculpture. Examination of all type material of the fossil taxa historically assigned to Hyperaulax reveals that only three species are separable (Partula americana Heilprin, 1886; Bulimulus americanus wakullae Mansfield, 1937; and Bulimus floridanus Conrad, 1846). The varietal names Bulimulus americanus var. partulinus and B. americanus var. laxus, both Dall, 1890, are indistinguishable from the nominate form in any important morphological character. Bulimulus heilprinianus, Bulimulus stearnsii, both Dall, 1890, and Bulimulus ballistae, Bulimulus remolina, Bulimulus tampae, and Bulimulus tortilla, all Dall, 1915, are synonyms of B. floridanus Conrad, 1846. The status of B. a. wakullae from northern Florida is problematic. Although clearly not conspecific with P. americana, it is tentatively assigned to Tocobaga new genus and is herein elevated to species level. The biogeography of Tocobaga new genus is tentatively discussed. Fossiliferous deposits in North America and South America have not yielded taxa with the combination of shell characters found in the new genus and relationships with other bulimulid genera are unknown. However, it is probable that the new genus, like other non-marine mollusks from the Tampa Member of the Arcadia Formation, dispersed to Florida after contact between the Caribbean Plate and the Bahama Platform (circa 38 Ma)”.

Auffenbach et al 2015

Reference:
Auffenberg, K., Slapcinsky, J. & Portell, R.W., 2015. A revision of the fossil taxa assigned to Hyperaulax (Gastropoda: Odontostomidae), with the description of a new genus (Gastropoda: Bulimulidae). – The Nautilus 129: 54–62.

Digital field work: the next step?

Bill Frank has already been doing some very clever detective work in and around Jacksonville, Florida on the occurrence of Bulimulus aff. sporadicus (e.g., here and here). Today his next message read: “Was using Google Street View this afternoon on my computer to “drive” or maybe I should say “mouse” around Jacksonville looking for Bulimulus sporadicus. Much to my surprise I found a location where it appeared that Bulimulus were present but the Google imagery wasn’t high enough in resolution to be absolutely sure plus the imagery was dated April, 2013.

Capture

Although in the past I have used Street View to view snails after I had first visited the location and confirmed their presence, today’s find, if confirmed by an on site visit, would be the first time that snails would were found solely based upon street view. So I jumped in the car and drove downtown to the location in question which is on Deer Street underneath the US-1 overpass. Upon arrival I found Bulimulus in the exact location as depicted in Street View on the concrete wall in somewhat modest numbers. However on the other side of the road live specimens were present in large numbers on another concrete wall. After looking around for a bit I changed my estimation from hundreds to probably tens of thousands of snails being present. The ground was just white with empty shells and represents the most specimens I have ever seen at a single location which is really saying something. This location within the past couple of  years has undergone a complete transformation due to road/overpass construction which makes the find all that more impressive (i.e. the snails had accomplished this in a relatively short period of time)”.

Detailed photos of the locality can be found in this document: Deer Street

So one might ask, will malacological field work turn into a digital exercise? Perhaps the saying of football coach Johan Cruijff may be apt in this context… “Je ziet het pas als je het doorhebt” [you see it when you get it]. Bill’s previous experience undoubtedly helped him a lot, but still: Chapeau for this digitally savvy malacological detective!

Color-full and catching the eye

Under this ttitle an iconographic study of Liguus shells from the 17th-beginning of 20th century just has been published. The first book in which a Neotropical snail, L. virgineus (L., 1758), was illustrated we are aware of was Philippo Buonanni’s Recreatio mentis et oculi. This appeared in 1684.

Buonanni1681

The illustration of species from this genus is followed through time, with comments on their (current) classification, until the first full-colour photographs in Simpson’s 1920 book “In lower Florida wilds”.

Unfortunately there are some glitches in the text, and the table appears to be in very small print in the hardcopy (but should be more legible in the PDF); the bold print intended for some text in the table has not survived the editorial process. The correct file is given below (link).

IcongrLiguusT1_*

Reference:
Breure, A.S.H., Álvarez-Lajonchère, L. & González Guillén, A., 2014. Color-full and eye-catching: an iconography of Liguus land shells (Gastropoda: Orthalicidae). – Archiv für Molluskenkunde 143: 1–19.

Photo of the day (156): Drymaeus

The previous post evidently led to some excitement in Florida… Bill Frank sent the the following message and photos:

“These are the two that I got out of the palm tree yesterday in Twelve Mile Swamp. They are the largest and nicest specimens that I’ve ever found.  I guess that it was worth it to have figured out how to retrieve them from 12-15 feet above ground. Obviously since I’m less than six feet tall and my rake is less than that, I had to do some jumping……….“

Keep jumping Bill, these are lovely creatures 🙂

P6070002 (2)jjP6070019 (2)jjP6070007 (2)jjP6070043jjj

Photo of the day (155): Drymaeus

This time the “Photo of the day” is another video link. Bill Frank caught these specimens of Drymaeus dormani (W.G. Binney, 1857) crawling around. Or perhaps better: in a race to the bottom…

Ddormani1

https://www.youtube.com/watch?v=8HmSbUYbS9o

And another one:

Ddormani2

https://www.youtube.com/watch?v=lyZ77JiF4Ns

Many thanks Bill for sharing these! And perhaps I should consider to rename this series…