Looking closer, however, the flowers of Symphionema are uncommon relative to the majority of Proteaceae. First, they are borne in a relative loose spike rather than densely packed in a condensed inflorescence. Then, the flowers are single, not in pairs as in the large subfamily Grevilleoideae. The flowers are also more or less radially symmetrical (actinomorphic) and the styles, hardly visible in my photographs, do not extend beyond the rest of the flower. Previous and ongoing work by Peter and myself suggests that these traits are probably ancestral in the family (e.g., see this paper on floral symmetry in Proteaceae we published this year with colleagues from France).

This of course does not imply that Symphionema looks like the ancestor of Proteaceae! For instance, the combination of spread out tepals and yellow, upright anthers (the part of stamens containing the pollen) is suggestive of buzz pollination by bees (as we suspect for the flowers of Sirdavidia solannona we discovered in Gabon three years ago). This has not been proved yet, but if true, this highly specialized pollination mode probably evolved rather recently and is likely not ancestral in this family.

As we understand it today, Symphionema sits with its sister group Agastachys (a genus endemic to Tasmania with a single species, Agastachys odorata) in a tiny subfamily, Symphionematoideae, that split from Proteoideae (the larger subfamily that includes Isopogon, Petrophile, and most South African genera) 80-90 million years ago (according to this paper that we published in 2009). Last, Symphionema actually has another species, Symphionema paludosum, which grows in lowland, swampy habitats along the coast of NSW. I can't wait to see it on one of my next bushwalks!!

For more information, see:

• NSW Flora Online (PlantNET)
• Flora of Australia Online
• Atlas of Living Australia

Just one month before leaving the city where I have lived for the last nine years, I thought it would be appropriate to present the namesake plant: meet Paris, a plant genus of 24 species in family Melanthiaceae!

Specifically, I'd like to introduce the species Paris quadrifolia, which I met in flowers for the first time two weeks ago, during my annual field course in the volcanic mountains of Auvergne. Apparently, the species has a very broad distribution in Europe (see this map), but in my experience is more commonly found in the understory of mountaineous forests on calcareous soil. It was particularly abundant in the beech (Fagus sylvatica) forests around Lac Pavin, where we spent the week.

The species is very distinctive for having only four broad, verticillate leaves. This explains the second part of the species name (quadrifolia). The first part (Paris), which has nothing to do with the city, may also refer to the pairs of leaves (according to this source), or to the Greek mythological character of the same name.

But what stroke me most this time was the realization that its flowers are tetramerous, meaning with floral parts (sepals, petals, stamens, carpels) in sets of 4. This is unusual for monocots, the larger group that includes about 25% of all flowering plant species. The vast majority of monocots have typical trimerous flowers, with parts in sets of 3 (as in tulips, lilies, irises). However, botanical rules are full of exceptions (which makes botany so much more fun!) and Paris quadrifolia is an extraordinary one, especially as it is paralleled by the peculiar set of four leaves.

Looking at it closer reveals more distinctive features. The floral bud is elongated and pointed and could easily be confused with a leaf bud. The perianth is differentiated into broad green sepals and narrower petals, which are also green (an exception in monocots, where most flowers have only one kind of perianth parts, the tepals, which are usually brightly colored). The stamens look like pointed arrows due to the long connective extensions beyond the anthers. Last, the four fused carpels have a very unusual dark purple color, with four free styles. Eventually, they will produce a dark blue berry that looks like a large blueberry, but is poisonous!

According to descriptions such as this one, Paris is in fact a variable genus when it comes to floral merism, ranging from 3 to 8. Paris used to be a member of Liliaceae, but now belongs to the small family Melanthiaceae. However, unlike most former members of the Liliaceae who have now moved to various families in the order Asparagales, Melanthiaceae remain in the order Liliales. In total, Melanthiaceae have 17 genera and about 170 species. These include Veratrum and Trillium, which is quite famous in North American temperate forests and looks like the more exuberant, but totally trimerous (both leaves and flowers) version of Paris quadrifolia!

Some of you may have wondered why I have posted so many plant pictures on social media recently. Some of you may even have been bothered by it and do not see the point. So I thought it is time to give an explanation and some context.
 
The vast majority of us scientists still keep most of what we do among ourselves. Apart from the occasional media coverage for some of our papers, the broad public is likely to never hear about our work and discoveries. Yet most of us are paid by public funds and scientific outreach is an official, still underappreciated duty of our jobs.
 
Until recently, I had so far myself felt little concerned with scientific outreach, but I have changed and there is good evidence that the community at large is also changing. For me, two important events did the trick. First, through my involvement in the MOOC Botanique produced by Tela Botanica and distributed to over 33,500 participants last year, I found myself in front of the videocamera of a professional film crew for the first time in October 2015. I had no idea how my colleagues and I would react (the experience felt much more like a first, awkward acting job than regular teaching), but I discovered that I really enjoyed it! I suddenly realized that video media were a form of communication with broader audiences that suited me. A few days later, I was on a plane to Borneo (Malaysia), where my colleagues Thomas Couvreur, Renske Onstein, and I had organized a field trip to collect magnoliids (a group of flowering plants that I work on). The three of us decided to film our unique experience in the rainforest during these two weeks, and as a result I made my first movie ever (Nine Days in Borneo)!
 
So how does this relate to the #discoverplants photo series? Last year, I was invited to a very interesting meeting in Amsterdam to discuss the future of plant systematics (the science of describing and understanding the evolutionary origin of plant biodiversity). This meeting was very inspirational and an important outcome was our conclusion that we, plant systematists, must learn to communicate and engage much more actively with the general public to help portray a more positive and exciting image of our fascinating field (see this report Sean Graham and I wrote about the meeting). Most of us really love our jobs and are passionate about our research. We are also very lucky: the living organisms we work on are magnificent and most people can appreciate that, no matter how little they might know about plants. So communicating about plants should be easy! During the meeting, I opened a Twitter account. I mentioned that I always intended to write a regular blog post such as “Flower of the month”, but never found the time or energy to do so, and a colleague suggested that maybe we should start a new hashtag on Twitter, #discoverplants, to share plant photographs that we find particularly interesting. This would take very little time and might actually be more enjoyable than the pressure of writing a fully informative blog post every time. And so I tweeted my first plant pic about a year ago!
 
As most of my friends and colleagues know, I am obsessed with flowers. They are the topic of my current research and a central feature of my teaching, so it is natural that most of my #discoverplants tweets should focus on flowers. I also take a lot of photos of plants all the time (as anyone who ever hiked with me has painfully learnt!). I spend hours and hours sorting, identifying, and labeling my plant photos (a great way to learn and memorize new species). I use some of these pics for teaching and conference talks, but most of them (currently > 16,000 photos) are never seen by anyone else. Thus, tweeting plant photos regularly seemed like an attractive way to share what I see and get excited about.
 
I have a personal connection and story with each species I portray (all photos are mine), be it a particular group of plants that I work on, a field trip, or a common species of our campus at Université Paris-Sud. I have not attempted yet to tell an informative story in 140 characters, but I always make a point of giving the full scientific name (species, family, order) along with the location. In doing so, I intend to raise public awareness that flowers are not just pretty things: they are the topic of scientific research too, they are much more diverse than most people realize, and each species in the World has a unique Latin name that allows us to communicate accurately among botanists of all origins (much more than common names in English, French, or any other language).
 
I started tweeting photos of species from plant groups I have been working on, such as Proteaceae, Magnoliidae, and Ranunculales. Some of these photos feature the flowers from an unusual, personal angle, usually after partial dissection to reveal the inner male and female organs (stamens and carpels). After a long pause, I decided to take advantage of the spectacular display of Spring to tweet one species a day, featuring both native and exotic plants from our campus (which is unique in France for also being a botanical garden). I did so for two continuous weeks (end of March / early April 2017). This has been a very interesting and rewarding experience, but I have decided to change the format. It is too frustrating not to be able to communicate the full story behind each species, so I am hoping to start my original idea of writing a short blog entry for a different flower each month.
 
So that is the story of #discoverplants. I am certainly not alone in the game of tweeting flowers (other botanists have been doing so with extraordinary success), but I am glad to contribute. If you like it and think this is useful, do not hesitate to follow me on Twitter, like, retweet, comment, etc. And do not hesitate to contribute yourself to the hashtag if you have interesting photos you want to share! This could be even more fun as a community and I am convinced we can make a significant impact through this and other ways of sharing our fascination for the extraordinary diversity of plants that is all around us, every day!