More Pine Rocklands

I've written before about a project on the endangered Pine Rocklands ecosystem of South Florida that I'm working on with my colleague Ben Baiser at UF and our master's student Lauren. We just went down to the Miami area for another field trip and it was great to see this habitat at another time of year - the previous trip had occurred in the fall. We managed to see a few more fern species that we had not seen on the last trip, as well as a few that are starting to become regulars.

Pleopeltis polypodioides

Vittaria lineata

Acrostichum danaeifolium

Acrostichum danaeifolium 

Anemia adiantifolia

Psilotum nudum

Psilotum nudum

Palm tree with Nephrolepis

Ferns in the news: weird sex

Photo by Harry Roskam

It's always a good day when ferns make the news, so the last few weeks have been pretty great! Carl Rothfels and colleagues have determined that two ferns alive today, but whose ancestors diverged from one another around 60 million years ago, have hybridized to form a new (although sterile) species. The new species is a hybrid between two different genera, Cystopteris and Gymnocarpium, and its name is Cystocarpium roskamianum. Intergeneric hybrids are very rare, because it becomes more and more difficult to be interfertile the more diverged two organisms are from one another. We often consider species to be units that are distinct from one another reproductively (although this is frequently untrue, particularly in plants), and genera are implicitly assumed to be even more so. There are four other known intergeneric hybrids in ferns, including Dryostichum singulare, a hybrid between Dryopteris goldiana and Polystichum lonchitis, but none involve parental genera as anciently diverged as Cystocarpium's. The authors use the analogy that this would be like a human and a lemur mating and producing offspring – the genetic distances involved are similar!

The story has been covered by a number of news outlets. Links are below, and I'm pleased to add that I was contacted for a comment for the NPR piece, which I very happily gave. 

• NPR: 'Weird' fern shows the power of interspecies sex
• Nature News: Fern hybrid does not mind the gap
• ScienceDaily: Distant species produce 'love child' fern after 60-million-year breakup
• IFLScience: Distinct species produce hybrid 60 million years after their split

OTS Fern Course

I just got back from spending three weeks in Costa Rica, attending a special course on Tropical Ferns and Lycophytes from the Organization for Tropical Studies (OTS). This course was first offered in the 1960s, and not again until 2008. I went on the 2008 course as a student, and returned this time as a visiting faculty member. We spent a few days in San Jose and then a week each at two OTS field stations, Las Cruces in the southern part of the country, and La Selva north of San Jose in lowland rainforest.

Las Cruces is particularly fun for the bird life, and many beautiful species show up for the daily offering of bananas outside the dining hall:

Blue-crowned motmot

Male green honeycreeper

Silver-throated tanager

Speckled tanager

And now just a few of the dozens (possibly hundreds) of ferns we saw over the course of three weeks...

Tiny sporophytes of Asplenium holophlebium

Hymenophyllum 

Ophioglossum

Hymenophyllum sporangia with green spores apparent 

Two members of Gleicheniaceae, Sticherus (darker green) and Gleicheniella (lighter green)

Gleicheniella

An tree tipup with incredibly dense fern gametophytes

Fern resource: Ferns and Lycophytes of the World

If you're looking for information and pictures of ferns, check out Ferns and Lycophytes of the World. This site is a great repository of information about ferns and lycophytes, and serves as a "digital herbarium", connecting collection information with keys, floras, photos, and more. Contributors to the site include a number of fern and lycophyte experts based all over the world, and you can sign up to contribute yourself if you're interested. 

Ferns in and around Archbold Biological Station

My most recent field trip was to go fern-hunting in central Florida. My friend and colleague Eddie Watkins from Colgate University escaped the onset of fall in the north to come visit sunny Florida for a few days. We set out to collect spores of various fern species in order grow and include them in a study we're doing on fern mating systems. We visited Archbold Biological Station, and a Florida state park called Highlands Hammock. Both were beautiful, and with a diverse set of species at each location from which we were able to collect lots of fertile spore material.

Vittaria lineata 

Tree trunk covered in mosses, fern gametophytes, and young fern sporophytes

Ceratopteris thalictroides 

Lygodium microphyllum, one of two invasive Lygodium species in the southeastern U.S.

Lygodium microphyllum

Lygodium microphyllum

Ferns at Archbold

Pine Rocklands project and field work

A few weeks ago I went on the first field trip for a new project I'm involved in with a colleague here at UF, Ben Baiser, looking at phylogenetic relationships of plants in a unique, endangered habitat in South Florida. The pine rocklands is a highly fragmented habitat that is only found on the Miami Rock Ridge, the area in and around Miami and its surrounding metro area. The pine rocklands exist in patchy fragments throughout this area, and in one large patch in the Everglades. Our project is focused on understanding food web dynamics within and between separate pine rockland fragments, and the first step is to identify and DNA barcode all of the plant species.

While we intend to collect all 500+ species found in the pine rocklands, my main interest is of course the ferns. Here are photos of the fern species we've found there so far, with more still to come!

Anemia adiantifolia

Anemia adiantifolia

Anemia adiantifolia

Vittaria lineata 

Pteris bahamensis

Pteris vittata

Psilotum nudum, the first time I've seen it in the wild!

Pleopeltis polypodioides 

A tree-load of epiphytic ferns and bromeliads 

Florida blue and orange! Asclepias and Sisyrinchium.

Ferns in Belgium

Our last stop for fieldwork on our European fern tour was Belgium. We were hosted by Ronnie Viane of the Biology faculty at Ghent University, and he shared with us his fabulous home fern garden and extensive personal herbarium collections before taking us out to do fieldwork in the Ardennes. We hiked through some beautiful forests and fields, and ended up at a roadside wall that had more Asplenium species in one place than we had seen anywhere else on the trip! It was a fantastic end to our field collections.

Beautiful fortress in Ghent

Dryopteris filix-mas happily ensconced in the city center.

Cathedral and medieval caste in La-Roche-en-Ardenne

Asplenium trichomanes ssp. quadrivalens

Snails hanging out and enjoying the calcium-rich rocks

Asplenium fontanum, not seen anywhere else on the trip and our final field collection!