POSTCARD from Mexico N°12

(By Fernando Rivadavia, March 13th-14th and March 20th - 21th, 2004) 

Two in One

                Time flies, so here goes two weekends in one postcard...

                On the weekend of March 13-14, I was joined on my Ping hunts by fellow CPers Bob McMorris and Mike Manna. I picked them up at the Mexico City airport on Friday afternoon and from there we drove nearly 600km before stopping for sleep. Because of heavy traffic leaving Mexico City as well as heavy out-of-season rains almost all along the way, we only stopped at around 2am.

                Initially I had planned to take Bob & Mike on a drive around the states of Veracruz and Puebla to look for P.emarginata and check out a few P.moranensis sites. But last minute ideas and I suggested that we instead go N to Nuevo Leon. I’d just been there the weekend before but there was still plenty to see. It was a much longer drive than Veracruz, but Bob & Mike agreed (mostly because the number of Ping species we’d probably run into was higher!).

                We spent the 1^st night in Matehuala – only a few hours actually, since we were up at sunrise and heading still further N. Our first destiny was a dirt road between the towns of Galeana and Rayones where P.rotundiflora and P.immaculata had been collected in gypsum hillsides. I still hadn’t seen either of these 2 species in the wild. I was hoping to catch them in flower, although I wasn’t really sure when in the dry season they flowered.

                We spent all morning exploring several small dry canyons and calcareous walls, having our 1^st encounters with the maddeningly prickly vegetation of the northern Mexican deserts – beginning to accumulate what would be quite a substantial collection of scratches and imbedded thorns & spines in our bodies by the end of the weekend. Although we literally paid in sweat and blood, we found no Pings that Saturday morning.

                The herbarium information I had mentioned a certain distance along the road, but we couldn’t find any gypsum habitats where they were supposed to be. We went back and forth and finally gave up on that stretch of the road. Driving on for a few more km, I suddenly glimpsed something familiar out of the corner of my eye. I immediately recognized the white gypsum soil and sparse vegetation on a mountain not so close to the road. We had to cross quite a long stretch of prickly vegetation to reach the area, but that didn’t stop us. And here we finally found Pings, at about 1500m altitude.

                In the deeper & shadier parts of steep valleys in the gypsum hills we found plenty of winter rosettes and numerous spent reddish flower scapes, but unfortunately no flowers. We assumed it was P.rotundiflora, although a bit smaller than I expected. Although growing mostly on pure gypsum, we also found some plants in neighboring dark soil.

                But where was P.immaculata? Supposedly it grew in the same gypsum habitats as P.rotundiflora. The main problem was that none of us really knew what we were looking for, whether it formed a winter rosette, above ground or below, if it would have flowers, etc. We continued climbing up the mountain, each one exploring a different ravine. When we were ready to give up, Mike shouted out something from the distance. At 1^st I couldn’t make out what it was, until he climbed out of the gorge he was in. He’d found P.immaculata!

                But actually Mike wasn’t sure if it was P.immaculata, so I hollered back to him to collect some and meet Bob and I back at the car. After a long wait, Mike finally showed up and sure enough he had P.immaculata – with a flower even! He’d found them on gypsum soil that was not so shady and more open than the P.rotundiflora habitats (although both faced north). And what a tiny flimsy little plant it was! P.immaculata was reduced to small underground rosettes of hairy succulent green leaves. The short inflorescences were red and the flower minuscule, covered with short white hairs and shaded in light yellow around the base of the lower lip. There was no corolla tube, the throat led directly to the spur, which had a reddish-pink tinge.  

                I don’t know how Mike spotted the white P.immaculata flower against the white gypsum background. Actually I think he 1^st saw the red scapes. Either way, it was a damn hard plant to spot, so kudos for Mike! The hardest part was over, knowing what P.immaculata looked like and where it grew, we’d have much less trouble finding it again.

                Driving further on, we saw more gypsum habitats at about 1350m and this time closer to the road, fortunately. We stopped to explore and once again found both P.immaculata and P.rotundiflora, the former in more exposed habitats above the ravines and the latter in the deeper shadier parts. We saw loads of both species, tons of inflorescences in fruit, and although it seemed like the end of the flowering season we were lucky to find a single flower of each species. Yet the P.immaculata flower was a bit deformed, unfortunately. The central lower petal lobe, which is usually large and apron-shaped, was about the same size as the 2 lateral lower lobes and had a dried shriveled tip.

                I was obviously happier with the intact P.rotundiflora flower, which ended up being the 1^st and last of the trip. The petals were a light lilac color, as was much of the corolla tube. Around the throat were light yellow patches and many white hairs. There were also purple patches right behind the yellow, both colors showing through on the outside of the tube. A little more purple was present towards the back of the tube and finally the spur was reddish. As for the rosettes, we found several which were apparently breaking dormancy. Maybe the freak rains that had been falling since Thursday had broken their dormancy?  

                All that day while driving along the Galeana-Rayones road, my eyes kept wandering to the east, where I could see a tall white mountain. According to my maps it was called Cerro El Potosí and was ~3700m high. But was that white gypsum soil on top or maybe some white rock like quartzite? We headed back to Galeana and then took the dirt road which according to the map led all the way to the top of Cerro El Potosí. It was sure a long way up and the road was pretty bad. We passed by habitats which looked very promising for species like P.moranensis, but strangely found nothing. The most surprising find was near the top of the mountain: SNOW! That’s what the white stuff was! The previous day’s rains had fallen as snow above ~3500m and had still not melted away. What an unexpected surprise – as was trying to drive along that narrow slippery snow-covered dirt road! I’d never driven on snow before, I believe.  

                It seems like the drive down Cerro El Potosí was even longer, probably because it got dark along the way. Luckily we found a hotel in Galeana and didn’t have to go too far. We were dead tired, after hardly sleeping the night before, driving around all day, and climbing steep hillsides with lots of loose rocks & prickly vegetation. Early to bed, and early to rise again the following day, my car seemingly creaking and tinkering more & more with each passing kilometer (the poor thing has had a bumpy few months with me... and very intense too!).

                On Sunday we started out heading S to Zaragoza, which I had visited the weekend before in search of P.cyclosecta. This time I was following a new lead I’d received from Eric Partrat during the week, a possible new species close to P.immaculata, which will supposedly be published by Hans Luhrs as P.nivalis in the near future. It was said to have been found in a gorge near Zaragoza. A week before I wouldn’t have known where to begin searching for it, but now that I knew what P.immaculata looked like and where it grew, I thought we had a much better chance of uncovering this new plant. But I have to admit I was a bit lost, since I had explored 2 gypsum hills in the vicinities and had seen nothing. Although I might have missed those tiny plants...

                So 1^st thing I did was drive back to one of the gypsum sites I had hiked around. The 3 of us combed the hillsides for about an hour and found no Pings. It seemed too dry, even the N-facing sides. Looking down the valley towards Zaragoza, I realized the surrounding mountains were heavily forested on that side. Could it be more humid over there? So down the road we went towards more gypsum hills I remembered seeing just outside Zaragoza. One of these looked particularly different as it had a sparse cover of pine trees. Hmmmm.... suspicious. But how to get there? It was a bit of a distance from the road. We actually 1^st tried driving along a dry riverbed, until we could go no further. On our way back over the loose rubble, we found a dirt road which surprisingly led straight to our goal! 

                Almost immediately after beginning to explore the base of the gypsum hillside, we spotted P.immaculata-like plants: reddish flower scapes sticking out from a darker spot in the white soil. There were loads of plants covering the N side of the hill at about 1425m altitude, and we were able to find a total of 4 open flowers. The 1^st impression was that it was P.immaculata. But slowly we began noticing differences, starting with the dormant rosettes which seemed larger. The flowers were possibly a bit larger too and VERY different in shape, starting with the spur which was shorter and fatter. They were white like P.immaculata, but had longer and more numerous white hairs around the yellow patch at the base of the lower lip and the two upper lobes were much larger and wider as well. As for the 3 lobes of the lower lip, these were wedge to heart-shaped (no large apron-like central lobe like P.immaculata) and the two lateral lobes were proportionately more similar in size to the central one. It was actually a lot more similar to P.gracilis.  

                So is this P.nivalis worthy of a new species? I’m not sure. It definitely has its differences from P.immaculata, but they are undoubtedly closely related to each other. I’ll leave this question to the experts...

                From Zaragoza we headed back through Aramberri and stopped at the P.kondoi site I’d found the weekend before, at about 1425m altitude. I thought it would be a quick stop, just to show Bob & Mike another Ping species. But we ended up staying quite a while longer since I discovered that what I had seen the previous week was but a mere fragment of the total population and it wasn’t even the main habitat. I’d seen P.kondoi growing in a dry streambed between 2 hills, protected by larger plants. Climbing a bit higher, we found lots more plants (which seemed healthier too) growing on vertical rock, either in cracks or islands of vegetation. I enjoyed studying again the variations in flower shape, size and colors. The biggest surprise was the obvious change that had overcome the plants after a few days of rain. The leaves had apparently absorbed the water, grown, and become thicker & crunchier, breaking out of dormancy. The previous week the rosettes had been more closed up, redder, smaller.  

The habitat of Pinguicula reticulata near Aramberri.   Photo : F. Rivadavia	Pinguicula reticulata near Aramberri.   Photo : F. Rivadavia
Pinguicula reticulata near Aramberri growing among cactus.   Photo : F. Rivadavia	Impressive cluster of Pinguicula reticulata near Aramberri.   Photo : F. Rivadavia
A deeply veined flower Pinguicula reticulata near Aramberri.   Photo : F. Rivadavia	A deeply veined flower Pinguicula reticulata near Aramberri.   Photo : F. Rivadavia
Pinguicula reticulata flowering in habitat near Aramberri.   Photo : F. Rivadavia	The flower of Pinguicula reticulata can be very variable.   Photo : F. Rivadavia
Pinguicula reticulata near Aramberri.   Photo : F. Rivadavia	Impressive cluster of flowering Pinguicula reticulata near Aramberri.   Photo : F. Rivadavia
Pinguicula reticulata growing in cracks of rock neatr Aramberri.   Photo : F. Rivadavia	Impressive cluster of flowering Pinguicula reticulata near Matehuala growing in cracks of rock.   Photo : F. Rivadavia
A deeply veined flower of Pinguicula reticulata near Matehuala.   Photo : F. Rivadavia	Impressive cluster of Pinguicula reticulata near Matehuala.   Photo : F. Rivadavia
Pinguicula reticulata near Matehuala.   Photo : F. Rivadavia	A red rosette of Pinguicula reticulata near Matehuala.   Photo : F. Rivadavia
Pinguicula reticulata near Matehuala.   Photo : F. Rivadavia	A deeply veined flower of Pinguicula reticulata near Matehuala.   Photo : F. Rivadavia
A light veined flower of Pinguicula reticulata near Matehuala.   Photo : F. Rivadavia

                From there we began our long drive back to Mexico City, although there were still a few hours of sunlight and possibilities of finding more Pings. We were hoping to find P.esseriana/ ehlersiae, of which we had collection data from a nearby town. We couldn’t find the exact place, but decided to explore a mountain on the road to Matehuala, not far from this city. It was a difficult climb up a steep valley, but almost near the top, at about 1825m, we began finding P.kondoi growing mostly in cracks and holes and in islands of vegetation on near-vertical rocks, very similar to what we’d seen at Aramberri. There were some beautiful forms with very heavily veined flowers. I guess I’ve finally understood where to search for P.kondoi and now know why I didn’t find any at El Huizache. I just didn’t go far enough up the valley to explore the vertical rocks.

                And that was the last Ping we saw on that trip. From there it was a straight drive back to Mexico City, where we arrived around midnight. With this last trip to Nuevo Leon, I’ve pretty much covered most of the Ping species native to NE Mexico, with the exception of P.laxifolia, P.debbertiana, and P.gracilis. It brings my total to anywhere between 25-30 species, depending on your taxonomic opinion. Considering all the thorns and spines I’m still pulling out of my body, I wonder if it’s really worth it....

                So after 2 weekends hunting Pings in the desert, I decided it was time for a change: on March 20 I went Ping hunting in the humid coastal rainforest of Mexico’s Gulf Coast. I had to work in Jalapa (or Xalapa), Veracruz state, for a week. I was at an ecology institute where they had a botanical garden with a small but nice CP collection. I also had a chance to check out the herbarium and saw a few collections of what appeared to be pygmy P.moranensis from the vicinities of Jalapa. On Saturday morning I decided to check these out. I found one of the populations near a small town called Las Minas, about 50km NW of Jalapa. They were growing at ~2250m, on cliffs and in clayish soil by the road.  

                But they weren’t pygmies... quite the contrary. I think I found some of the largest P.moranensis flowers ever, not to mention the huge size of the winter rosettes. These were no pygmies! The most interesting part is that the rosettes were breaking dormancy, with normal leaves beginning to grow out from the center of the succulent winter leaves. I guess because of the high humidity in this area, P.moranensis dormancy is shorter than elsewhere. The flowers... well other than finding plants with up to 3 open flowers each, what can I say, I seem to have a knack for uncovering variability in plants. There were large and small ones, long or short, petals rounded or rectangular-ended, with dark marks around the throat or without, spurs curved forward or pointing straight back. But it was the colors that I really enjoyed. Flowers varied from deep purple, to lilac, all the way to deep pink.  

                From there I drove another 50km or so further N to search for the real goal of the day: P.emarginata. It supposedly grows on cliffs by rivers in rainforest areas around 1400-1600m. I drove around for a few hours, triangulating between the towns of Teziutlan, Atzalan, and Tlapacoyan (and altitudes from around 800-1800m). There were surely lots of deep ravines near the roads, covered with tree ferns. Yet I couldn’t find either of the 2 places I knew for sure P.emarginata grew: Cascadas de Oligui and Tatzayanala. And nobody I asked seemed to know either. So it was up to me and my “Ping nose” to sniff out a site.

                I spotted a real interesting cliff by a river, at about 1350m, and best of all it was the closest and most accessible site I could find (Oh no, here goes another link to Eric’s “Are Ping hunters lazy or not?” page!). It was difficult finding a place to leave the car and I wasn’t too happy with the spot. But it was close... (yeah, yeah, go ahead Eric!). I headed down the ravine towards the river, looking for a place to cross, which wasn’t as easy as I thought it would be, but at least the rocks weren’t too slippery. Although the water was clear, it was sadly full of litter.

                Once across, I had to climb the ravine on the other side, which was mostly loose dirt mixed with rocks, eroding from the cliff (which I realized was not bare rock, but mostly dirt). And I also noticed there were plants clinging to the wall, light green in color... This only made me scramble faster up the hillside, not minding the thorns so much (yes, thorns AGAIN, even in the rainforest!).

                And yes they were Pings, my “nose” did not fail me! They covered the wall and even the ground where large slabs of dirt had eroded from the cliff. There were a few flowers too. BUT PURPLE! It was P.moranensis, not P.emarginata! Damn, I sniffed the wrong scent!! All the flowers were out of reach, too high up, so I didn’t really waste much time there. I noticed that most rosettes still had the summer leaves from the previous season surrounding the winter rosette, as well as new summer leaves beginning to emerge from the center.  

                I tried searching a bit more along the riverside, hoping to find P.emarginata, pushing my way through the thick underscrub, but only saw more P.moranensis on walls. After having driven around for so long between the 3 towns and not having turned up any P.emarginata nor found other interesting sites to check out, I realized I’d have to leave empty-handed. I simply needed more location data before returning for another attempt at finding P.emarginata.

                I returned to Mexico City and on Sunday March 21 I decided to revisit an area I’d been to 6 months ago, on my 1^st Ping hunt alone in Mexico. I went to Taxco, in Guerrero state, around 150km S of Mexico City. I 1^st drove up to Cerro El Huisteco, where I’d previously seen P.heterophylla, P.moranensis, and U.livida. Comparing to 6 months ago, it was amazingly dry! Where before I’d seen P.heterophylla growing on the banks of a small stream, it was now bone-dry ground littered with dead tree leaves. I was able to find the dead leaves of P.heterophylla and I dug one up out of curiosity. It was a rootless bulb sheathed in a stringy brown mass, protecting the light-green thin succulent winter leaves. This site was at around 2225m and there were thousands of plants further up all along the road, maybe to 2350m.

                The cool thing is that these P.heterophylla DO NOT face N like most other Pings here in Mexico, but E and S! I’d suspected as much, but I didn’t have a GPS with me last time and the sun was high in the sky, so I hadn’t been able to confirm my guess. The only other exceptions to the “always on the N-facing side” rule I’ve come across so far are P.crenatiloba (an annual, not worried about how much direct sunlight it will receive in the winter – when it’s dead!), P.gigantea (grows at low altitude in a rainforest area with very high humidity), and P.hemiepiphytica (grows in ultra-humid rainforest/ cloudforest, where light is already partially filtered by tree tops). So why doesn’t it grow on the N side like (almost) everybody else? Well my guess is that it doesn’t need to. Species that face N do so in order to avoid desiccation of their winter leaves. But when the winter leaves are buried beneath the soil like those of P.heterophylla, protected in a bulb by a sheath of dead leaves, it doesn’t really matter what’s happening on the surface. I wonder if this is true for other bulb-forming species...

                Further up the mountain, I found P.moranensis with no signs of breaking dormancy yet nor any flowers. I’ve been seeing lots of variation in P.moranensis winter rosettes. They vary from convex mounds of winter leaves lying more or less flat above the soil, to compact onion-like bulbs buried in the soil with only the tips showing, often forming a concave bowl with the outside leaves longer than the central ones (and sometimes the outside leaves are bent over the central ones). The ones at El Huisteco were of this latter kind while the ones at Las Minas were of the former kind. The shape of the winter rosette might be an important taxonomical character, but to what degree? I suspect the winter rosettes owe at least a little of their shape to the level of desiccation suffered by each plant. I did see some variation depending on where plants were growing.

                Surprisingly, I found no signs of U.livida, suggesting it grows as an annual. Its sites were completely dry. In fact all these sites I was visiting seemed drier than what I’d seen up in the deserts of NE Mexico. Could it be that because it’s colder up N, there’s also more water condensation at night, guaranteeing a constant water supply during the winter?

                Before going down the mountain, I also checked an area where I believe my friend Ruben found P.parvifolia, but I saw nothing, maybe I was in the wrong place. And before heading back down to Taxco, I decided to check one last place, on a side road heading to a town on the other side of El Huisteco. There I’d found more U.livida and P.moranensis growing on a road bank dripping with water, at about 2275m altitude. Fortunately this site was wet and I found both species still growing there. So apparently U.livida is an optional annual, dying out only if its habitats dry out. The flowers were colored in white and lilac-blue, with mustard-colored markings at the base of the lower lip. As for the P.moranensis, no flowers were present, but there were still summer leaves and some didn’t even have winter leaves!  

                On the way out of Taxco I stopped where I’d previously found P.parvifolia and 2 plants of P.crenatiloba growing by a stream at around 1850m altitude, in an area lightly forested with pines & oaks. The oaks had lost nearly all their leaves and there were plenty of pine needles covering the ground as well. The stream was GONE, no water whatsoever. I couldn’t even recognize the streamside habitats where I’d seen the Pings. Although I searched all over, I could find no sings of P.parvifolia (and obviously P.crenatiloba), so I didn’t have a chance to study the winter bulbs.

                On this visit to Taxco, I have to admit I was hoping to catch an early flower or two of P.heterophylla and P.parvifolia, since I might not be around anymore at the height of the flowering season of these species, around May/ June. But I guess it just wasn’t a lucky weekend for me. Oh well, after having seen so many interesting Pings over the past months, I really can’t complain about one bad weekend...