POSTCARD from Mexico N°7

(By Fernando Rivadavia, December, 12th 2003) 

Oaxaca Trip 3

        Friday the 12th of December was a holiday in Mexico (day of the virgin Guadalupe). I took this opportunity to return for the 3rd time to Oaxaca and spend the extended weekend there searching for CPs. I'll be going to Brazil for a month starting December 19, so this was my last chance to see Pinguicula in the wild in 2003. I'll only return to Mexico in February, and then probably for only 2-3 more months. 

         So I've been a bit anxious these past few weeks, knowing I had to see all the annual species before leaving in December, since they're already dying down and will probably only start growing again around July. There are also several perenial species which are presently going into dormancy and will be leafless and flowerless until at least June or July.

         Last week I fortunately found a nice site with the annual P.crenatiloba. Having already seen P.lilacina, P.takakii, and the new species from Tonala, the only annual species I'd be missing out on was P.sharpii from Chiapas. Unless P.clivorum (=P.barbata) is also annual, I may still see this one too.  

         As for the Mexican perenial species, there are several which I've only seen summer leaves and no flowers, but may still see flowers early in 2004, like P.esseriana, P.laueana, P.debbertiana, P.parvifolia, P.imitatrix, P.heterophylla, P.acuminata, P.kondoi, etc. Yet there are other species which are already dormant and will only show new leaves and flowers in ~6 months time, like P.cyclosecta, P.colimensis, P.macrophylla, P.orchidioides, P.calderoniae, P.elizabethiae, etc. So I don't really plan on doing any more trips to search for  species of this latter group, unless I am lucky to still be around here in June/ July.

         Then there's the case of 3 relatively unknown species from Oaxaca : P.greenwoodii, P.conzattii, and P.mirandae. The latter 2 are closely related and for several years were confused, until P.conzattii was published earlier this year. P.conzattii was discovered by Alfred Lau near Santiago Nuyoo and is in cultivation, although still rare 15 years after its discovery. 

P.mirandae apparently never made it successfully into cultivation and was only known from a few collections around Santa Maria Ixcatlan, ~200km N of Santiago Nuyoo. As for P.greenwoodii, practically nothing is known about the species, not even where it's from. 

         But my major worries centered around the problem of getting OUT of Mexico City on Friday. I had to leave very early because the exit for the highway to Oaxaca is very close to the Basilica de Guadalupe, which is the destination for pilgrims arriving from all over the country on the day of the virgin. Although I left home before 5:30am, it still took me an hour to get out of the city due to traffic. All along the highway through Puebla state there was plenty of traffic too, due to numerous bicycle groups pedaling with huge portraits of the virgin around their necks, runners with torches, and endless cars and trucks of all kind carrying pilgrims. And in ever town I passed that day there were commemorations of one kind or another, often with parades and fireworks.

         My first objective on this trip was P.mirandae. I had already attempted to find it on my 2 previous trips to Oaxaca, but had not been able to reach the small village of Ixcatlan, confused about which was the right route. 

This time I was certain I had to take a road heading E from highway 135, but wondered whether it would be easy to find this species or not. All I knew was that it grew on vertical walls at ~1200m altitude next to a river and that it supposedly flowers in November and December. This meant it might be my last chance of seeing P.mirandae in flower. I had no way of knowing if it would continue flowering for a few more months, or whether it was about to finish flowering. 

         I only arrived in Tehuacan (in SE Puebla state, bordering Oaxaca state) at around 9am. 

The Tehuacan valley is very dry, with many beautiful cacti and other xerophytic vegetation.

        I was really curious to see in what kind of habitat P.mirandae grew. What hidden humid corner had it chosen as its ecological niche in that vast desert ? Heading SE from Tehuacan towards the city of Oaxaca, highway 135 climbs from ~1000m to ~2000m altitude, and crosses the border into Oxaca state. I had driven by this road on my way back to Mexico City during my 1st trip to Oaxaca in November and was amazed with the views of dry canyons and huge escarpments to the W as I descended towards Tehuacan. So amazed in fact, that I missed something really interesting on the passenger side of the car.... 

         This time, as I drove up the mountains, I couldn't see much of the canyon to my right (passenger side). So I was admiring the dessicated hillsides to my left, when all of a sudden at ~1800m altitude appeared a huge calcareous cliff. I hadn't seen this cliff before and my attention was drawn to the sight of huge bromeliads of the water-tank type (Vriesia??). These were very numerous on the cliff face and it struck me as a rather odd view, since to me these compact rosettes were typical rainforests epiphytes - and not desert dwelling plants. Bromeliads in deserts are usually of the prickly Hechtia type with narrow leaves which couldn't hold any water. So I immediately thought: there must be above average humidity in this spot.

         I stopped the car as best as I could along the narrow roadside, whipped out my GPS, and sure enough the bromeliad-covered wall was facing N. There must be Pinguicula on this wall! Instinct carried me scrambling up the steep hillside made up of loose rocks piled up around the base of the calcareous cliff faces. Too bad it only helped me get up, 'cause by the time I finally stopped and looked down, seeing the road WAY below, instinct had chickened out and left me on my own ! Man do I get myself into some horrible places sometimes in the excitement ! 

         Anyways, almost as soon as I reached the base of the 1st vertical wall, I spotted a handful of Ping winter rosettes with young flower buds growing directly on the rock or in dry mossy patches. The leaves were thick, succulent and covered with short sparse white hairs. What were they? Taxonomy of winter rosettes is NOT my strong point, and I quickly remembered the flowerless rosettes of possible P.laueana Ed and I had found at Nuyoo and the Sierra de Mixes. At least this time there were flower buds on these plants, so I wouldn't have too long to wait before finding out what they were. They could be P.moranensis, or hopefully P.mirandae (although I was about ~100km away from the type location and ~600m higher), or maybe even a new species... 

        I slipped and slided over the rubble, heading towards the base of another cliff and sending several rocks tumbling down to the road. I could hear the larger rocks rolling seemingly endlessly down before finally hearing the "chunk" as they made contact with asphalt below - hoping all the time I wouldn't accidentally soon follow suit.

         At the base of the next wall, I found a single rosette on bare rock, also with a young scape. This part was not completely perpendicular and I was able to climb the wall to a flatter area a bit further up. Calcareous rock is very rough, which helps you get a good foothold. But it also crumbles easier than you'd imagine, which makes it extremely dangerous when you've got a 50-100m drop behind you. Fortunately, I got away from this one safe, although with several deep scratches and cuts in my arms and legs due to the jaggedness of this coral-like rock, which very easily cuts into the skin.

     Catching my breath on the flatter area, I found more rosettes of this mysterious Pinguicula growing in dry mosses inside vertical cracks a few cm deep.
Once again there were several young scapes, but none mature enough to even hint at what the flowers would be like. Hmmm, cracks seemed to be a nice place for the plants, maybe a little more humid. I looked up and saw that there was a horizontal crack in the rock, just out of reach. I found the right foot and handholds and as I pulled myself up, peering into this crack, lo and behold, there were 2 white flowers! It was P.mirandae !! 

     Albeit the difficult position, I was able to take numerous pics of the flowers while somehow still holding onto the cliff. It was strenuous, but worth it. These were possibly the 1st shots of P.mirandae (with or without flowers) in the wild. The flowers had a surprising mix of colors. The petal lobes were white, the corolla tube was flattened laterally, with a constriction near the center where there was a sharp 90 degrees bend. On the outside, the tube was colored a dark purple-pink with darker lateral stripes, the apical half containing 5 greenish-yellow stripes along the fusion points of the petals. These appeared more yellowish from the inside of the tube, which was also thickly covered with white hairs. 

         I finished taking pics and was heading towards the base of another wall when I heard a police siren from below, obviously calling the owner of the "abandoned" car. Damn! I was forced to climb down before the policeman called somebody to tow my car away or something. I slid down, practically surfing over the loose gravel. My mistake, since this was exactly why the policeman was looking for me: I'd accidentally dislodged a few large rocks which had fallen in the middle of the road. Oooops! He also told me I was in risk of falling off the cliff, getting robbed, bla-bla-bla. So I apologized and said I'd be on my way, as well as showing him pics of P.mirandae in my digital camera, uselessly hoping to attract some sympathy... 

         Although I'd only seen a small number of P.mirandae and only 2 flowers,
I decided to forget Ixcatlan and go straight to Santiago Nuyoo to attack my 2nd objective of the trip: P.conzattii. I didn't know if it would be easy to find P.conzattii or not, so **IF** I had time at the end of the trip I could try returning to Ixcatlan to search for the type location of P.mirandae. 

         Nuyoo is around 30km from the nearest asphalt and the dirt road is unfortunately not one of the best I've seen in Mexico, with lots of rocks scraping the bottom of the car along the way. Three weeks before, Ed Read and I had been to Nuyoo, where we found P.moranensis (?) as well as those beautiful stalactites covered with P.laueana(?) winter rosettes. But by the time we got down from the mountain it was already around sunset and although we examined every possible place until it did get dark, we couldn't find P.conzattii. I'm don't think twilight was the main culprit however, BECAUSE IT WAS RIGHT IN OUR FACES!!! 

        As I drove along the dirt road towards Nuyoo again, I had this one spot in my mind, where Ed and I had last stopped to search for P.conzattii. It was at ~2600m altitude, right above some small cliffs looking down at Nuyoo and Yucuhiti far below. The large trees covered with epiphytes growing around the walls proved that this area received plenty of humid air year-round, in order to sustain the cloud forest. The area is mostly deforested though, with most of the trees growing right around the wall or on it.

        And there on mossy patches in the semi-shade of the trees was P.conzattii, just about visible from the road!! I guess they were just TOO obvious, or maybe their flowers and scapes were simply larger than I expected, because I passed right by the once again! I walked along the top of the cliff and took a short trail that led to the base of another cliff. But these were all S or W facing walls, so I wasn't really paying attention, not knowing that P.conzattii is an exception among Mexican Pings (which always seem to grow facing N, where there is less sunlight and therefore less dessication in the dry season). 

         Disctractedly walking through the forest, I looked at a rock face ~20m to my right, which was when I finally spotted some white flowers. I swear I almost walked on, thinking they were too big to belong to P.conzattii. But, just in case, I thought I'd better try crossing the thicket to the base of the wall to check all those flowers. WOW! It was truly P.conzattii !! I couldn't believe how many plants and flowers there were. The calcareous rock was completely dry, yet the layer of dead mosses told a different stiry from another season. 

        There were no summer leaves left on P.conzattii, only winter rosettes which were very characteristic (I remembered Lau's pictures) and yet very different from it's cousin P.mirandae. What they did have in common, I found out, was how the rosettes practically burst in your hands when disturbed. In fact I saw several P.conzattii with scapes arising from a mass of detached succulent leaves with pink bases spread over the soil surface. What had popped them, I don't know. 

        The flowers of P.conzattii were not entirely white as I 1st thought from afar. The majority were mostly white, with only the petal apices suffused in lilac.Sometimes it was just the very edges, but sometimes the purplish blush spread further down towards the tube or even down to he spur. There were numerous white hairs spread all around the petals, but were thicker around the often greenish base of the throat. This color sometimes showed through on the outside of the tube as opaque green strips and was often also visible on the top areas of the tube. Inside the throat, I could see two narrow elevated yellow ridges. 

        Although the corolla tube was horizontally flattened like that of P.mirandae and also curved downwards, P.conzattii did not have a constriction near the middle of the tube, curving slowly downwards instead of forming a sharp right angle. The spur was straight (curved in P.mirandae) and light-green in color. Most flowers had a notch at the tip of the spur, and it seemed like they were actually double spurs. I did find flowers with narrower spurs which didnt have the notch. Curiously, these were on smaller flowers too. 

         Although there were numerous flowers and many plants had a few scapes each, I saw no fruit. Strangely enough, the scapes seemed to just die off from the tip. While P.mirandae seemed to just be starting to flower with all those young scapes present, P.conzattii appeared to be near the end of its flowering season since I only saw a few young inflorescences. I was surprised at the numerous white hairs thickly covering the scapes, especially near the base. 

         Exploring the area a bit better, now knowing what I had to look for, I finally saw the plants growing almost by the roadside which I'd somehow managed to miss twice already, once with Ed. Again there was a large number of plants, fortunately most of them out of reach. On a shadier mossy patch I did find a few summer leaves still alive, although not looking great. Here I realized P.conzattii did not grow on open cliffs exposed to sunlight. Although facing W and S, strangely enough, they only grew on vertical rocks semi-shaded by trees and bushes. 

         I was very intrigued by the P.conzattii habitat, wondering why it could survive on W and S-facing walls when most other Pings apparently couldn't. It was obvious this spot must have a constant flow of humid air year round, but what forces contributed to this? I am always interested in discovering patterns (what ecological conditions allow a species to grow where it does, what characterizes a specific habitat), hoping this will help me find other sites and maybe new species by pointing out new areas with potential. Well, I've developed a hypothesis, let's see what people think...  

         After 3 months in Mexico I've noticed that there are several Pinguicula species which seem to grow in valleys facing the ocean. These are often far from the ocean, but the mountains that define the valleys would nonetheless be the 1st natural barrier encountered by humid ocean-blowing winds that are probably constant year round. Because of this, the valleys are often covered in thick tropical rainforests. Sometimes the Pinguicula which inhabit these areas are found at low altitudes on cliffs along the valley (P.gigantea, Pinguicula from " Tlanchinol"), or else on higher ground towards the end of the valley in cloud forests (P.hemiepiphytica, P.laueana), or even higher up at the very top of the last mountain or cliff (P.conzattii, Pinguicula aff. laueana "Nuyoo", and maybe P.calderoniae, P.laxifolia, P.utricularioides).

          If I am correct and this is true, it means that anybody wanting to find new species of Pinguicula in Mexico and Central America should search such ocean-facing valleys, all the way from the lowland cliffs to the ends of the valleys on the mountain peaks. And remember to search everywhere, since the N-facing rule is broken by the constant high humidity in these valleys.

          Realizing that Nuyoo may be one of these special spots, I tried exploring a few other dirt roads hoping to reach some cool cliffs I could see to the E. But it was getting late and I was really tired, having woken up at 5am as usual on these trips. So I headed back to the asphalt to find a place to crash for the night. On the 1st day I'd already managed to find 2 of my 3 goals for that trip. One left to go...      Before tackling my 3rd and last goal, I decided to explore a road going S from Tlaxiaco to a place called Santiago Yosondua, where Alfred Lau had supposedly found stringy-leaved Pinguicula - most likely P.heterophylla, but what the heck. Frost was all over the fields along this road in the early morning (altitude was above 2000m). It was mostly pine forests along the way, with few interesting spots. I spent most of the morning exploring this road, but didn't find a single Pinguicula.

          Back in Tlaxiaco, I headed SW along highway 125 towards what I believed to be the "Zacatepec road", to search for one of the most mysterious of all Pinguicula : P.greenwoodii. Although Martin Cheek's publication of this species mentioned the type location as "Iacatepec road", Ed. Read obtained information directly from Ed Greenwood where "Zacatepec road" was written instead. Since we couldn't find Iacatepec on any map, Ed. Read and I concluded the correct spelling must truly be Zacatepec. The problem is that we found 2-3 Zacatepecs in Oaxaca state! And worse of all, none of them seemed to be 30km from the coast, as Greenwood claimed for P.greenwoodii. 

         The Zacatepec closest to the sea was a Santa Maria Zacatepec on hwy 125. This road is an endless and terribly winding road slowly descending from Tlaxiaco at ~2500m altitude towards the coast, passing through numerous pueblos full of speed bumps without warning signs. I drove 150-200km of this torture, before turning back when I was close enough to the coast and far enough from the mountains. You see, there was more confusing and conflicting information in this mess which I haven't mentioned yet. 

         As I drove towards and past Zacatepec, I realized that something about the P.greenwoodii collection info not fitting in. At ~30km from the coast the altitude was more like 500m and the road only reached 1500m at ~150km from the coast! What could be wrong? At least one part of the info was probably right however : the habitat. It was described as a colony with ~200 plants growing on a dripping, shaded limestone cliff face in mixed cloud forest. The good news was that at ~1400m on this road I did find a N-facing calcareous cliff. The only problem was that it was dry as hell and a bit hard to reach. I was only able to search the very base near the road and did not see a single Pinguicula. 

        I had seen this cliff on my way down the mountains, but did not stop by the river at the base of the cliff because there were numerous policemen doing some sort of training exercise with their German Sheppard dogs. Not a good moment to search for CPs I think... Luckily they weren't there when I finally did get back to the cliff. But I have to admit I didn't explore it as well as I could have, mostly because I had a booming migraine headache from having driven all day long on winding roads, while at the same time checking the roadsides and the GPS. 

        So anyways, this cliff MAY be the type location of P.greenwoodii, since it was the only such cliff I found along that road, not to mention that it was close to 1500m. Could Ed Greenwood have menat to say 130km from the coast?? Or maybe he collected the plants in a completely different place far away... Giving up on P.greenwoodii (for the time being...), I kept on driving N towards Huajuapan, where I spent the night. On the way I stopped by the site near Tonala where Ed Read and I had discovered the new annual species as well as a long-leaved species, possibly P.heterophylla. I didn't have time to stop by the P.medusina site since it was already late in the afternoon. But I did notice that there are several gypsum habitats further away from the road between Juxtlahuaca and Tonala - an interesting place to explore, for anybody who is in the area. 

         At the Tonala site, I quickly found the exact spot where the new species grew 3 weeks before. But where were they? OK, it was nearly dark already, difficult to see and all, but searching better I noticed they were truly gone! I had a hard time  finding dead rosettes even, but eventually I did pick out a really ugly barely-alive plant. Wow, in 3 weeks they'd gone from full growth to practically gone. I wonder if it had truly gotten that dry in 3 weeks, of if maybe the culprit was frost. I'd seen frosts both mornings on this trip, although at higher altitudes. But I did find some nice plants still in flower growing on the vertical walls of the small canyon where P.heterophylla(?) also grew. I was hoping to explore other nearby areas for more of this new species, but I'll have to leave this for somebody else, maybe next season.

         There was also a cliff just N of Tonala which I'd seen with Ed Read and
which I now realized looked like the P.mirandae habitat, with large bromeliads and all. But I wasn't able to explore it because after checking out the P.sp."Tonala" site (which I'd been rushing to reach before dark, although my head was killing me), I went to sleep in the car for over an hour. So it was dark by the time I drove by this wall. Well, one more place to explore in the future. 

         The following morning I left Huajuapan at sunrise and drove N back to the P.mirandae site. I wanted to go to Ixcatlan and hopefully see more plants, but I'd gotten a flat tyre the day before and hadn't had time to fix it. And since there were maybe a few dozen km of dirt road to Ixcatlan, I didn't want to risk it. So I just went back to the site I'd found along Hwy125, hoping that no policeman would show up this time and I'd be able to find more plants in flower. 

         I first tried climbing down from the road, this way no policeman could complain I was sending rocks showering down on the road. But I found no P.mirandae, so I decided to go back to the area where I'd found them before. Once again, in the excitment, I climbed to where I shouldn't have climbed. It's not that I'm afraid of heights, but I just don't like climbing cliffs, OK? And I really put myself into some dangerous spots, almost slipping at one point and ripping the palm of my hand open - but at least I managed to hold on and not splatter myself on the road for the policeman to pick up later. It made me wonder whether it was really worth taking such risks just to photograph two flowers of P.mirandae side-by-side.... 

         And to make climbing even worse, I also had the "luck" of encountering a catterpillar covered in long branching bright fluorescent green hairs. Yep, my left hand grabbed this baby while I was climbing. Still have little red dots all over my hand. (I've decided to start telling these details, so that people will stop telling me how "lucky" I am, as if I'd won a trip to Bali. :):)  ) 

            But the good news is that I found more P.mirandae than I'd seen before and several of them in flower. Like I said above, I even found a nice spot with 2 open flowers right next to each other, but of course this was in the most difficult spot of all. My legs trembled uncontrollably while I tried to photograph these flowers! And guess what? Yes, the pics did NOT come out in focus!! 

         At least I saw other flowers and got several nice pics of these. What was interesting is that these were a little larger than the 2 flowers I'd seen 2 days before only a few meters away. Furthermore, flowers with white petal lobes did not seem to be the norm. Most were more or less tinged in lilac, especially near the edges like P.conzattii, but more diffused. Could it be age, more sunlight, or what?  In the publication of P.mirandae there's a drawing of a winter rosette with some stringy stolons that look more as if they belong on a small Utricularia species. I didn't see anything like these and wonder whether they aren't some other little plant which was accidentally collected with P.mirandae.

          Before heading back to Mexico City, I took a road from Tehuacan to Orizaba, in hopes of finding that P.sp."Puerto del Aire" on Eric's site. The views along this road are pure desert most of the way going up a valley. Although it doesn't seem to climb much, all of a sudden the vegetation changes completely to a very humid type and fog drops on you like a thick blanket. And then you go steeply down from about 2400m to 1800m in a few km. I'm sure this highland pass must be the spot where the Pinguicula was found, but unfortunately I didn't see it. It looked good enough, but maybe they were all dormant already. Nonetheless it was a nice drive, too bad the fog didn't let me see much of the view though.      

And this trip wraps up my travels in Mexico for 2003. 

        I can't even begin to describe how fullfilling it was to finally get the chance to  see so many Mexican Pinguicula in the wild. The plants are beautiful, the scenery magnificent, the landscape breathtaking, the people tremendously kind, and the food made even better by the hilarious names most have. I owe big thanks to Ruben, Marlene, Adolfo, and Zamudio for all the help, kindness, friendship, and/or company on trips. Also to Ed. Read for joining me twice down here and bringing most valuable help and information. And of course I can't forget Eric Partrat and Laurent Legendre, who gave me a crash course on Pinguicula over the last few months, tutoring me all along the way. Congrats for their great work on their web page too.

      I'm heading back home to Brazil now for a month and will hopefully have time to see another 20 or so Pinguicula species when I get back to Mexico, hehehe!! In fact how many species did I see in 3 months? Hmmm, let me count : 

Species I certainly saw in the wild:

1. P.acuminata

2. P.agnata
3. P.conzattii
4. P.crassifolia
5. P.crenatiloba
6. P.ehlersiae
7. P.gigantea
8. P.gypsicola
9. P.hemiepiphytica
10. P.heterophylla
11. P.lilacina
12. P.macrophylla
13. P.medusina
14. P.mirandae
15. P.moranensis
16. P.orchidioides
17. P.potosiensis
18. P.takakii

Species I may have seen (no flowers):
1. P.debbertiana
2. P.esseriana
3. P.kondoi
4. P.laueana
5. P.oblongiloba
6. P.parvifolia
7. P.rectifolia

Undescribed taxa I saw:
1. P.sp. "Molango"
2. P.sp."Tlanchinol"
3. P.sp."Tonala"

Wow, a nice amount, huh?? :):)
            

Take Care,

Fernando Rivadavia