POSTCARD from Mexico N°3

(By Fernando Rivadavia, November, 7 to 9th 2003) 

Dear Ping friends,

   I had a FANTASTIC weekend! And this time I was lucky to have the company of local Pinguicula-fanatics Adolfo Ibarra and Ruben Resendiz to help me look for plants, as well as pass the hours on the long drives to each Pinguicula site. We had some really interesting talks throughout the 1600km we drove this weekend.

     We left on Friday ~6pm and arrived in San Luis Potosi at ~11:30pm (2h stuck in traffic on the way out of Mexico City...). On Saturday morning we started out early, driving ESE towards Rioverde. This road passes by the type location of P.potosiensis, which is a synonym of P.moranensis according to Dr. S. Zamudio. We found these plants growing on N-facing cliffs by the road at ~2000m I think. As usual (for P.moranensis) there was lots of variation in leaf color (green to reddish). Most of the plants had well-formed winter rosettes already, although summer leaves were still present (some really large ones too). Unfortunately there were no flowers nor signs of flower scapes, which was odd since at all other sites I've seen so far of P.moranensis there were always flowers/scapes.

     From Rioverde we headed NW towards Villa Juarez, where we turned S along a dirt road into some really dry mountains towards a town called Buenavista. Supposedly there were P.gypsicola and P.takakii. Needless to say we were dying to see the famous P.gypsicola as well as the mysterious P.takakii.

    Fortunately the information we had was really good and the first place we stopped at was a hit! It was a short hill with its N face towards the road, at ~1300m alt. It was basically COVERED with P.gypsicola ! The vegetation was really dry, with lots of prickly plants like mimosas, agaves, hechtias, and cacti. It was sure a pain-in-the-behind walking around these and all sites throught the weekend. We all ended up full of scratches and punctures.

The impressive view from the hill, where Pinguicula gypsicola can be found. Photo : R. Resendiz	The habitat of Pinguicula gypsicola. Photo : R. Resendiz
Pinguicula gypsicola in habitat. Note the variation in leaf color.  Photo : F. Rivadavia	Pinguicula gypsicola flowering in habitat.  Photo : F. Rivadavia
A nice red coloured Pinguicula gypsicola in habitat, growing on gypsum. Photo : F. Rivadavia	Pinguicula gypsicola in habitat. Photo : F. Rivadavia
Pinguicula gypsicola in habitat, growing among all kind of organic material. Photo : F. Rivadavia	Pinguicula gypsicola in habitat, showing the winter rosette. Photo : F. Rivadavia
	Fernando Rivadavia posing close to an impressive cluster of Pinguicula gypsicola in habitat. Photo : F. Rivadavia

     P.gypsicola grew on the steeper parts of the hill, where there was probably less direct sunlight. Surprisingly, the white gypsum(?) soil was humid and there were even some odd patches of mosses here and there. Some P.gypsicola grew on bare rocks. Unfortunately my knowledge of geology is rather bad, but this rock was greyish, with rough edges, but would crumble if enough pressure was applied. There were plants in full growth while others already had large winter rosettes. The leaves were often tinged in reddish-pinkish.

     And there were still some flowers too!! These were dark purple-pink, with some variation in the width of the petals. Also, some had a white spot in the center, while others didn't. We didn't see any developing scapes and judging by the large numbers of scapes in fruit it seemed like flowering season was truly coming to an end.  

     We searched all around but couldn't find any P.takakii. The biggest problem is that we didn't really know what to look for. We only had a picture of a flower that Eric Partrat sent me as a link and made by Stanley Lampard (IPSG). But this was of little help since it seems that the most important thing is to know the right micro-habitat where each species occurs. I know from experience with CPs in Brazil that this is often very difficult the first time around. But after you've seen them once, you start finding tons of them - if you were able to recognize what it is that defines the micro-habitat (this is not always easy).

     We didn't find any P.takakii growing on that hillside with P.gypsicola, but we think they probably were present because of the hybrid we found. Yep, we found 3 plants growing together of what was apparently a hybrid between P.gypsicola and a smaller species, possibly P.takakii. These hybrids formed flat rosettes with pinkish-red leaves that were triangular but with rounded tips. A beautiful plant!!

      From this site we headed a few km further along the road and stopped by another hillside facing N. This hillside was not as steep as the previous one, so there was more sunlight, as well as more damn prickly plants! We didn't see any P.gypsicola but after searching around for ~10 minutes Ruben shouted out that he had found SOMETHING. It was a Pinguicula for sure, but which one?

     It was small, less than 2cm in diameter, with rounded leaves, the edges heavily curved inwards, reddish-pink scapes up to ~5cm high, and flowers with a beautiful mixture of colors. The free ends of the corolla were a light bluish-lilac, the tube white with dark-pink stripes, the anterior underbelly of the tube yellow, and the tip of the spur yellow too. This more or less matches the several descriptions of the flowers in the herbarium data we have, but dos not match the picture Eric sent us. So it appears that we did find the true P.takakii, but then what is that plant in Eric's picture???      The habitat seemed very particular for P.takakii. It was abundant in a small area, mostly semi-shaded by larger bushes, growing in humid mounds of gypsum (?) soil with Selaginella (a common rosetted species). Although obviously an annual species, it will be a beautiful addition to any CP collection.

      Happy with the 2 species plus hybrid we'd found, we headed N and NE to search for some P.ehlersiae & P.debbertiana sites. We passed by areas where supposedly these plants grew, but our herbarium info was not that specific and we didn't see any habitats which looked like potential Pinguicula areas. We ended up returning to San Luis Potosi for the night.

     The next day we headed out at sunrise once again towards the town of Nunez. We'd passed by there the day before, but were not able to find the exact site mentioned in herbarium specimens for P.ehlersiae & P.debbertiana. We decided to explore a dirt road that led into a deep valley among high mountains, hoping that it would eventually lead us from ~1300m up to ~1800m where the plants supposedly grew.

     Once in the valley, we got out of the car and each one headed in a different direction to better explore the area. About 45 minutes later the silence still had not been broken by excited shouts of "I found it!" So we drove a little further up the road, which was really bad and rocky. We left the car where the road ended, at nearly 1800m and headed further up the valley on foot. It soon became almost a canyon, with very steep walls very close together. All of a sudden I realized that the soil of these steep hillsides had become a white clayish sort, similar to the one at the P.gypsicola habitat, but more humid. Although there were still cacti, agaves, and hechtias like the rest of the hillsides, here there were also some sparse long-leaved pine trees.

   And this is where we found the Pinguicula. What were they? We're not sure.

Supposedly, both P.ehlersiae & P.debbertiana grew there, but without flowers we could not tell. There were differences in leaf shape, size, color, and arrangement, but nothing that couldn't be attributed to soil, humidity, sunlight, or the presence of winter/ summer leaves. We'll have to go back there during flowering season to check them out.

     Unfortunately we got a flat tyre at this site and it turned out that the step was also punctured (company cars.), so we ended up losing a few hours trying to get out of this mess. We still had some hours of sunlight remaining at the end of the day and we headed N to highway 80, E to El Huizache, and then N along another dirt road for ~10km. We left the car at a small village and hiked E into some low mountains covered in dry prickly vegetation, where supposedly there were P.kondoi ~2km away. We had a GPS location for this plant, so we were very excited and hopeful - although a straight line according to GPS often means a much larger distance since it doesn't take into consideration the local topology, i.e. climbing up and down several hills.      As soon as we entered a valley we began finding Pinguicula on the N-facing side, at ~1500m. The rosettes were identical to the P.ehlersiae & P.debbertiana we'd seen earlier that day. It turned out that at least part of the plants were truly P.ehlersiae, since we actually found FLOWERS!

Close up of the rosette of Pinguicula elhersiae or Pinguicula debbertiana.   Photo : F. Rivadavia	Pinguicula elhersiae or Pinguicula debbertiana using all the free place to grow.   Photo : F. Rivadavia
Note how the rosette of Pinguicula elhersiae or Pinguicula debbertiana use all the possible most favorate place to grow.   Photo : F. Rivadavia	Note how the rosette of Pinguicula elhersiae or Pinguicula debbertiana use all the possible most favorate place to grow. Photo : F. Rivadavia
Pinguicula elhersiae without any doubts. Note the rich organic soil around the plant. Photo : F. Rivadavia	Pinguicula elhersiae without any doubts. Photo : F. Rivadavia
Pinguicula elhersiae flowering in habitat. Photo : F. Rivadavia	Pinguicula elhersiae flowering in habitat. Photo : F. Rivadavia

Although they supposedly begin flowering in January, we found a few plants with young scapes and 2 open flowers. One had just opened up and was still a bit hunched over, but the other was fully open and beautiful! They were a dark purple, slightly pinkish color with a white mark at the base of the lower lip.

     What we don't know is if we found P.kondoi or not. According to GPS, we went to the exact spot and found plants growing exactly as described, in cracks among rocks  But once again there were no significant differences in the rosettes which couldn't be attributed to ecological factors. Yes there were narrower leaves, redder leaves, leaves with borders bent inwards or not, etc., but nothing that we could point out as consistent. Without flowers it is apparently very difficult to distinguish between P.ehlersiae, P.kondoi, P.debbertiana, & P.esseriana (which supposedly grows in that area too, El Huizache is the type location).

      It's hard to believe that with such identical rosettes P.ehlersiae, P.kondoi, & P.debbertiana have such different flowers. Is it convergent evolution of the leaves for a similar habitat? Or do flower shape, size, and coloration maybe evolve faster than people think in Pinguicula ? Could it be that the subgeneric and sectional divisions of Pinguicula based on flower morphology are artificial?

     We returned to the car ~6pm and started the long drive S back to Mexico City, arriving at ~11:30pm. The trip was a complete success, I think we found every species that we set out to find, although we still need to confirm P.kondoi, & P.debbertiana. And more if you consider the cool hybrid.

I can't wait 'till next weekend !! 

Best Wishes,

Fernando Rivadavia