POSTCARD from Mexico N°5

Oaxaca -

(By Fernando Rivadavia, November, 19 to 23th 2003) 

Oaxaca Trip 2

                I picked up Ed Read at the Mexico City airport on Wednesday night, 19^th of November. Thursday was a national holiday in Mexico, which meant we’d have 4 days of Ping hunting in Oaxaca until Sunday. Heavy traffic out of the city slowed our progress a bit, but we only stopped at 1:30am at the town of Tehuacan in Puebla state, just N of the Oaxaca border. 

                On Thursday we were up at 5:00am and out by 5:30am heading SSW towards Huajuapan, where we hoped to see P.rectifolia although we had no precise location data. Desert vegetation most of the way and no sign of any Pings, which was a pity because I was hoping to compare P.rectifolia with  P.moranensis since the former is considered a synonym of the latter by Zamudio.

                Further along road near the town of Tonala, we suddenly passed an area  that reminded me very much of the P.gypsicola habitat I’d seen in San Luis Potosi earlier this month. The selaginellas and small xerophytic plants sparsely spread on white soil... was that gypsum too? “We’ve gotta search this area!!”.  I exclaimed, while stepping on the breaks. We got out of the car and began walking along the hillside, heading for the N-facing side, especially a small dry canyon between 2 hills. 

  Suddenly Ed began laughing half hysterically and nonstop, while looking down at the ground. I sprinted over to his side and kneeled down, where there was a tiny Ping species, obviously annual. It immediately reminded me of P.takakii, but it was overall smaller, especially the flowers which were white or light-lilac with a yellow blotch the base of the lower lip and the visible part of the sexual organs (is that called the column?) a darker pink-purple. The spur was short and fat, facing straight down. The older plants had a multitude of flower scapes, literally flowering themselves out, like P.crenatiloba also does. All these thoughts flashed through my mind in a fraction of a second as I looked at the plants, my mouth gaping wide open. I turned to Ed (who was still laughing) and repeated in an incredulous whisper, which soon grew to a shout of excitement: “Ed, this is a new species! We’ve found a new species of Pinguicula!”  

                I couldn’t believe our luck, the first Ping we find on the trip turned out to be a new species! I’d been dreaming of finding a new species of Pinguicula ever since I came to Mexico, but knew the chances were probably slim and did not really believe it would happen. It was an exciting moment for both of us, being my 1^st new Ping species and Ed’s 1^st new “whatever” species! 

                Later on, back on the highway and more calmed down, we carefully ticked off other possibilities such as P.sharpii, P.barbata, and other small species we did not know well, comparing with all the Ping publications we had with us in the car. Nothing matched our plant, it was truly a new species ! 

                But back on those gypsum hillsides, we realized there were numerous plants of this new species growing in a small area, the soil being crusty on the surface, but cool and humid below. We only found more of the tiny rosettes growing on the vertical walls of the small canyon, where we were overjoyed to find a second Ping species, this one with long narrow green leaves. Considering we were ~30km N of the type location of P.medusina, we assumed it was this plant. There were no flowers to help the ID, nor were there any plantlets growing from the leaf tips (a sure characteristic of P.medusina). But supposedly P.heterophylla does not grow in gypsum soils, so we thought they MUST be P.medusina. Until we found the real P.medusina...

                The type location of P.medusina was easy to find, a steep gypsum hillside next to a beautiful blue pond called Laguna Encantada. The plants were very similar to the ones we’d found a short while before, except that the leaves were reddish-pink in color and most had a tiny plantlet hanging from the tips. This only confused us further in relation to the identity of the previous plants. It was obvious there were differences, but the gypsum soil was supposedly one of the decisive characters. We saw other gypsum soils along that highway and I think I will return there to explore better in the next few weeks before the plants go dormant into their onion-like bulbs buried a few centimeters below the surface and covered by a thick layer of fibrous brown remains of dead leaves. 

                We took another highway heading NE towards Tlaxiaco, but our objective was a small dirt road leading off from this highway, heading S to 2 small villages called Santiago Nuyoo and Santa Maria Yucuhiti. The type location for the most recently described Mexican Ping species, P.conzattii, was along this road. Also, Alfred Lau had supposedly climbed a mountain near these villages and found P.agnata, plus a very beautiful form of P.moranensis with dark-pink flowers and white spots, and also a species apparently close to P.laueana with red-flowers and a yellow-tipped spur. 

                Sadly it got dark before we could better explore the numerous branching  dirt roads and we weren’t able to find P.conzattii, which was a pity because it is now flowering season for this species. We spent a long time trying to climb the  mountain where Lau had supposedly found those 3 different Pings. Too bad we weren’t sure if it was the right mountain nor even if those 3 species had really

been found there, since Lau’s memory was a bit patchy when Ed had transcribed the info. But then again, who’s memory wouldn’t be patchy after 20-30 years?!?! It was amazing he remembered the names of the villages at all. Ed and I could hardly remember the names of most towns 5 minutes after reading them on the maps!

                 So did we find the 3 species on that mountain? Hmmm, we’re not sure... Well, P.agnata we certainly did not see, this one is easy to recognize with or without flowers. But we did find P.moranensis-like rosettes with some reddish veins, growing on the lower shadier parts of a N-facing cliff. Further up the same cliff, in more exposed areas, we saw one of the most amazing sights of the trip.

                Hanging from the calcareous rocks were flat stalactite-like structures, made of mineral and organic deposits. On these rock curtains were hundreds of Ping winter rosettes, each with dozens of neatly packed succulent leaves. But depending on which side of the rock they were on (sometimes facing a bit more E or W), the plants sometimes still had a few summer leaves and these were a dark wine-red. Unfortunately none had flowers to help identification nor do we know enough about Ping winter rosette taxonomy in order to figure out if these were P.moranensis or something closer to P.laueana. If anybody can help, we’d really appreciate it, or else it will be a very long and exasperating wait for us until plants finally flower in cultivation...

  We climbed back down to the car, hurrying before it got dark. We even  attempted to find P.conzattii in the twilight while driving the ~40km back to the asphalt, but it was useless. The following day we once again woke up at 5am and headed out towards Oaxaca city and then further E to the Sierra de Mixes to  search for P.laueana. We had all the available info from Alfred Lau’s talks and articles on this species, as well as his photos, so we had high hopes. The dirt  road he described, which had just been opened in the 70’s, was fortunately now asphalted and easy to drive along, except for all the winding curves and several villages we had to cross, all full of speed bumps without any warning signs.                 

                The road from Oaxaca city started at ~1500m altitude, passing through mostly dry xerophytic vegetation and slowly climbed to 2500m altitude, reaching a humid cloud forest with lots of pine trees. We had our eyes open for a special kind of yellowish moss in which P.laueana grew in Lau’s pictures. There were many mossy banks along the road and we explored several of them. In one we even found some P.moranensis and there was a single large pink-purple flower,  but unfortunately it was high up and out of reach.

                A turn in the road seemed to lead into a more humid part of the valley (BTW, we were nowhere near the bottom of the valley, the road was closer to the mountains tops) and suddenly we began finding that famous yellow moss from Lau’s pictures. We jumped with joy when we recognized from our car window the scenery in one of Lau’s pictures, taken from the P.laueana site. Although it was taken farther up the mountain, we knew we were more or less at the right place. But without the red P.laueana flowers (which we believe are only present later on in the dry season), it didn’t really seem worth climbing past the thick vegetation to the mountain tops. We were hoping that in these ~30 years since the road had been built at least some P.laueana had made their way down the mountains and could now be found on cliffs along the roadside. 

                  Every single wall was heavily scrutinized as we drove by (and as our dizziness increased as a result of this effort!), and yet somehow we missed the spot. Only on the way back did we see the rosettes sticking to the cliffs. These were pretty high up, yet we could see green winter rosettes amid a few remaining reddish summer leaves, looking very much like some of the plants we’d seen on the rock curtains near Santiago Nuyoo – which only confused us further. So were they both P.moranensis or both P.laueana?? 

                There were not many plants and they were all out of reach. In order to get up close, I had to park the car in the opposite lane facing any oncoming traffic, right under the rosettes. We then took turns climbing on top of the car to take pictures. Fortunately, it was a very empty road and nobody drove by (cursing or laughing) while we were doing this...

A Pinguicula spot in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read	The supposed Pinguicula laueana in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read
Ed. trying to reach the rosettes. Photo : F. Rivadavia and Ed. Read	The supposed Pinguicula laueana in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read
The supposed Pinguicula laueana in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read	Impressive caterpillar in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read
The supposed Pinguicula laueana in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read	The supposed Pinguicula laueana in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read
The supposed Pinguicula laueana in the Sierra Mixe. Photo : F. Rivadavia and Ed. Read	Pinguicula moranensis in the Sierra Mixe Photo : F. Rivadavia and Ed. Read

             We returned to Oaxaca city and since there was still an hour or two of sunlight, kept driving on N to the Sierra Juarez to search for some P.orchidioides, which were supposedly everywhere according to herbarium specimens on a mountain crest halfway to Ixtlan. Sure enough, we found one or two spots with small populations in the oak forests by the road. Sadly all were flowerless, only a few dry scapes were present. I guess I’ll just have to hope I’m still in Mexico in ~6 months time, when they’ll begin flowering again, I’d love to see the flowers of this species.

                Not wanting to sleep at the bad little “hotel” at Ixtlan like the week before, I told Ed we should drive back down to look for a nicer place in Oaxaca city. Too bad the hotel we chose was also a nightclub and we had to endure loud music all night, not to mention having to wake up a tipsy man inside a pickup truck blocking our car when we left at 5:30am. 

                Halfway through the trip, start of the 3^rd day, up the road I drove again, N along Highway 175. At Ixtlan we turned briefly E to search for a site with P.heterophylla and P.oblongiloba, which was most likely P.orchidioides (according to Zamudio P.oblongiloba is only found further N, more or less starting off where P.orchidioides drops out). Walking through pine forests in early twilight we were utterly surprised to stumble upon a population of Catopsis berteroniana! I had never stopped to think that this species could be present in Mexico, much less up in the highlands above 1000m altitude. The plants were rather greenish, not the beautiful yellow color I’d seen on the Gran Sabana in Venezuela. And there was no water in the rosettes either, it seemed. Although not a bromeliad taxonomist, I’m almost sure it is this plant. There were several scapes but no flowers, only immature fruit. An older flower scape was covered with dozens of baby plants that had germinated from the fruit.

                We explored extensively in that area and saw nothing but a P.moranensis site I’d found the previous week. Only when we were almost giving up did we stumbled across a very nice population of P.orchidioides, but no sign of P.heterophylla. So we moved on, since that was not our main objective that day. What we really wanted to see were epiphytic P.hemiepiphytica. So back we went to Ixtlan, and then N again for ~60km along the curving road, past more P.moranensis sites. Reaching the top of the Sierra de Juarez at ~2950m, we stopped for quick pictures of the views, before starting the descent that would eventually lead us to the town of Valle Nacional at ~100m altitude, less than 50km further on.

                 I’d come out very frustrated the week before for not finding epiphytic P.hemiepiphytica. This time however we were armed with better location data – or so we thought. At the new designated spot, the mountainside was not N-facing and the trees had no moss cover. But a little further on both these things did come together at one short stretch of the road. The N-facing side was extremely steep however and we could only enter the forest for a short bit before it sloped too perilously downwards. As we admired an orchid on a tree trunk, I suddenly caught a glimpse of a smooth green something high up on a tree trunk, among the rough green mosses. Shouting out, I pushed through the dangling vines towards the tree and sure enough there they were, several Ping rosettes stuck to the tree trunk. We’d found them, epiphytic P.hemiepiphytica! We could even see flower stalks with green fruit. 

Searching for more plants in that area proved fruitless. It seemed like there was only a short stretch with mossy trees along the N side of that road. Nor could we climb down the mountainside any further. Wondering why the Ping rosettes were only growing so high up on the trees, I realized that they were on a very big tree, and not on the thinner younger ones. Could it be a tree-age related thing? We searched for other large trees and only saw some farther downhill. Yet no Ping rosettes were visible. Could it have to do with sunlight too? Maybe lower downhill it was too shady. So if P.hemiepiphytica wants light, who said they only grow on N-facing areas? Maybe the tree tops filter sufficient sunlight to allow them to grow facing other directions...

                So I suggested we head to the other side of the road, which was a very gradual S-facing slope. And there we found more P.hemiepiphytica growing high up on the larger tree trunks, basically facing all directions. We could see more green scapes on the P.hemiepiphytica, but no flowers. The rosettes mostly all had winter leaves appearing among summer leaves. Making our way through the hanging vegetation (often prickly), low branches, and fallen logs, we found other large trees with P.hemiepiphytica, I think all rosettes out of reach. But we did find one within reaching distance, and it was a very large rosette. Best of all, it had a HUGE open flower!! We saw the flower first, sticking outwards from behind the tree trunk. What luck, an open flower in November (they supposedly flower earlier in the wet season) and within easy reach of our cameras! 

                Many pictures later, and after searching the whole area for other flowers (but finding none), we headed back to the road, where we checked out the P.hemiepiphytica site I’d seen the previous week. We found one or two further places along the roadside where they grew and even found 2 more flowers! One was open, although not as nice or large as the 1^st one we’d seen, while the other had just folded over its petal lobes but was still stuck to the scape. This last flower had an immense corolla tube and shorter spur. I can now see why Zamudio created Section Longitubus (which also includes P.calderoniae, P.crassifolia, and P.utricularioides).

                We headed all the way down to Valle Nacional, where we stopped for a surprise visit at the house of a family that Ed had stayed with on 3 previous occasions. Unfortunately they weren’t all home, but we enjoyed it nonetheless. Very nice people and good food too! After about an hour, we said our goodbyes and headed N to Tuxtepec and then W towards San Bartolome Ayautla.                  The views to Ayautla are truly spectacular, passing by a huge artificial lake at the foothills of the 2000m-plus escarpment (I don’t know if it has a name) where P.gigantea grows. The huge cliff reminded me of a Venezuelan tepuy and I believe this one is also made of sandstone. Further in the background, we could see a ghostly silhouette of the majestic Pico de Orizaba, incredibly high as seen from our near sea level location. 

                  From our viewpoint on the road, the highest cliff of the escarpment was the “corner” between two cliff faces, one running N-S along the lake and another running E-W past Ayautla, getting progressively shorter until disappearing further up the valley. We wondered if P.gigantea grow only on the stretch next to Ayautla or throughout the cliffs, on both the E-W and N-S axis. We didn’t explore a smaller road that goes past the N-S axis, but we did check out the huge corner cliff using Ed’s binoculars. Yet we saw absolutely no sign of P.gigantea. 

                Only a bit further up the road along the E-W axis did we begin seeing the yellow patches, curiously even on an E-facing side, just like the big corner cliff. The impression I got was that P.gigantea did not really mind which way it was facing, as long as there was enough humidity to keep it from drying out. Possibly there was much more humidity on the cliffs lining the narrow valley where Ayautla is located (actually a very deep canyon) than on the huge corner cliff and N-S axis which faced the open lake.

                We only arrived in Ayautla around 4pm and imagined it would be a quick easy hike up to the cliffs peppered with yellow blotches of P.gigantea. HA! Were we wrong! We left the car partway up the hillside inside the small village of Ayautla, where apparently they are not used to seeing foreigners. Before we could even get out, our car was quickly surrounded by dozens of curious children who even followed us as we began our ascent. Like on the Sierra de Mixes, Spanish was not the 1^st language of these people, and some appeared not to speak it at all.

The trails thinned out slowly, climbing through stretches of forests and then corn plantations on hillsides that became increasingly steep. I couldn’t believe anybody planted anything in these rocky areas where erosion must make any plantation impossible after a few years. Between the plantations and the P.gigantea-covered cliffs there was a belt of low and thick bushy-thorny secondary vegetation, which we noticed we’d have to go through if we wanted to reach our goal. So Ed and I took turns throwing ourselves against the plants, slowly opening up a path. It took us maybe an hour to get past ~50m of vegetation to the wall and when we finally did, we were disheartened to see that the stretch of cliff we’d reached appeared to have no P.gigantea at all. 

                With the sun sinking behind the mountains and our morale going down with it, we realized we’d have to give up and return the following day and try all over again. We headed back down, our faces red and dripping with sweat, as well as all scratched up by thorns (like the rest of our bodies, whether exposed or not) and even bloody. Exhausted, we drove all the way back to Tuxtepec, since there were no hotels in Ayautla or anywhere else nearby. And that night we certainly needed a good hot shower more than on any previous night. Next morning we headed on back to Ayautla before sunrise, to start all over.

               We decided to 1^st try another section of cliff that appeared to be closer to the village but which seemed too vertical, worrying us with the possibility that we’d only be ogling at unreachable P.gigantea from below. After once again climbing past stretches of forest and plantations, we reached another barrier of thick secondary vegetation. Only a short distance away was the cliff, now visibly covered with huge colonies of P.gigantea. These grew much more compact than one would’ve guessed from Lau’s original pictures. Through the binocular, we’d seen similar thick colonies on other parts of the cliff we drove past on our way up.

               Again we began opening up a path through the thick vegetation with our bodies. If only we had a machete! At least the distance to this wall was not so great and it must’ve taken us about ½ an hour to reach the cliff base, located at nearly 800m altitude. We were directly beneath the large P.gigantea colonies, we could see flower scapes and the bluish flowers. But they were all out of reach. 

                Trying to walk along the base of the cliff was no easy or even feasible task. Fortunately, a short and not so difficult hike for a few meters to one side brought us around a corner where there was a small colony of P.gigantea growing within reach! And there was even an open flower too! What relief. After so much admiring them through binoculars, we finally had P.gigantea right in front of our faces. So we made the best of it, taking all the pictures we could, including of the larger colonies high above. 

                But soon we were thirsty for more. From the road we’d seen another rocky area that we believed was the famous site Alfred Lau had climbed up to. This place seemed to have more accessible P.gigantea and would hopefully give us some nice pics. So we hiked partially down the mountain and then across to towards this site. We got to a point ~200m directly downhill from where we wanted to go, but could not find a trail leading upwards. The prospect of having to open another path, and through such a large stretch of vegetation, was more than Ed and I could bear. It was a very anticlimactic visit to the famous P.gigantea site at Ayautla, but it would have to do. It was getting late in the morning and we still had to drive all the way back to Mexico City. 

                Back to the car we went, happy to have seen P.gigantea, but nonetheless feeling frustrated. It was sort of like what I felt the previous week when I’d found P.hemiepiphytica, but had only seen them on the roadsides and none on the trees. Yet we still had one final and very interesting goal, before our expedition was over. On the other side of the Mazateca Highlands, we wanted to search for the illusive P.mirandae. As far as we knew, this species is not in cultivation and no pictures of it are known, other than the ones in the original publication (which may actually belong to P.conzattii since at the time the authors thought they were the same). 

                It’s a long drive over the Sierra Mazatecas and back down again to the Tehuacan valley. We stopped to check out some P.moranensis along the way, before descending to the dry valley where P.mirandae supposedly grew. We were very excited with the prospect of wrapping up our trip with a practically unknown species. I’d driven by the area the week before, but was unsure if the right road to the site was one coming from the E or W. I decided to explore the one coming from the E, but when we found it, it was not much more than a pebbly trail through the desert. We drove for a few bumpy kilometers, until we realized that the GPS was marking less than 700m altitude. P.mirandae had been collected at 1200m and we sadly realized it was still too far away. With my city car, we were more likely to get stuck out in the middle of nowhere than of finding P.mirandae. Apparently, you either need a 4X4 to reach P.mirandae or else the road coming from the W is probably the correct one. 

                From there it was a straight drive back to Mexico City, where we arrived ~5 hours later due to heavy holiday traffic and other curious impediments (such as a slow-marching funeral procession blocking the whole road in a small village).  We’d missed seeing a few plants, but we’d seen some other very interesting species. And hey, on any trip where you discover a new species, I think you really can’t complain about anything else, huh ???