Field Report: 2018-08-10

El Japonés and the Dragon

A search for Matuda's Arboreal Alligator Lizard (Abronia matudai) and pitvipers


1
Volcano
10,000,000
Mosquitos
2/2
Target Species

In April of 1892, at the direction of the Japanese Foreign Minister (and samurai) Enomoto Takeaki, a commission of Japanese businessmen left Yokohama, Japan to explore the length of mainland Mexico's Pacific coast. Their report on mining and agricultural opportunities would spark a series of Japanese colonization efforts in the Soconusco region of southern Chiapas.

Some 30 years later, a 28 year-old Eizi Matuda joined the small waves of university-educated Japanese immigrants arriving in the agricultural colonies of the tropical Chiapan lowlands. In the decade that followed, he worked to establish himself in Mexico, introducing novel agricultural techniques on the Granja Fujino. By 1935, a steady income allowed Eizi (a biologist by training, and an experienced botanist) to turn his attention to cataloguing the region’s flora and fauna. His efforts yielded tens of thousands of specimens of over 4,000 species, including hundreds of undescribed species and several novel genera. While his collections were primary botanical, he was also able to secure over 5,000 birds and reptiles.

Among the reptile specimens was a single dragoncito – spanish for 'little dragon' and one of several Spanish names for arboreal alligator lizards. The lizard was found in the cloud-forests of Tacaná – a 4060m tall volcano towering above the Chiapan lowlands along the Guatemala-Mexico border. This specimen would later catch the eye of Norman Hartweg and Joe A. Tihen at the University of Michigan who were reviewing the alligator lizards of Chiapas. In 1946, Hartweg and Tihen designated this specimen as the holotype for the new species Abronia matudai.

The Japanese Botanist, Eizi Matuda
Matuda's lizard from the Volcán Tacaná

Since the description, additional specimens were found just over the border in Guatemala, but Matuda's Arboreal Alligator Lizard remains one of the rarer species known only from a handful of sites — all threatened by illegal logging. Campbell and Frost even include Abronia matudai among the list of species they expect to see functionally extinct during their lifetimes.

So when the HERP.MX Field Team had to make a return trip to the southeastern corner of Chiapas to survey for the Guatemalan Palm Pitviper (Bothriechis bicolor), the Abronia was a no-brainer addition to the target list.


Palm Pitviper Problems

In 1978, Jordi Juliá Zertuche and Manuel Varela published the description of a new species of pitviper, Bothriechis ornatus, from the same region in southeastern Chiapas, the Soconusco. Plagued by errors and failing to follow nomenclature code, the description was largely ignored before Miguel Alvarez del Toro synonymized B. ornatus with B. bicolor just four years later. Jonathan Campbell would later comment in Venomous Reptiles of the Western Hemisphere: "This description [of Bothriechis ornatus] does not differ in any significant way from the range of variation known for B. bicolor." That said, while the ornatus name might have been relegated to an obscure footnote, the snakes themselves are anything but.

An adult 'ornatus'-phase <i>Bothriechis bicolor © Hector Franz / HERP.MX
An adult ornatus-phase Guatemalan Palm Pitviper (Bothriechis bicolor)

Starting in 2013, HERP.MX's Chris Grünwald began taking a closer look at B. bicolor in Chiapas with an aim to both refine our understanding of the species' distribution within the state and to determine the true taxonomic standing of Bothriechis "ornatus". We found B. bicolor at a handful of Pacific versant locales in Chiapas, and all of the populations matched the description of ornatus, all of them except one: Volcán Tacaná.

Volcano Bound

After a grueling drive, the HERP.MX Field Team arrived in the foothills of the cloud covered volcano. On previous trips we'd secured a handful of specimens from a single slope — all similar to 'classic' Bothriechis bicolor. This trip aimed to see how far that form could be found next to the suspected boundary — a line HERP.MX's Chris Grünwald anticipated to fall near the Río Huixtla. We were pleased when a handful of pitvipers made an appearance, all of which matched the classic bicolor


Cloud forest habitat for Bothriechis bicolor
On the trail...
An adult Bothriechis bicolor

A neonate Guatemalan Palm Pitviper (Bothriechis bicolor)
A neonate Guatemalan Palm Pitviper (<i>Bothriechis bicolor</i>) © Jeffery Chad Williams / HERP.MX
A neonate Guatemalan Palm Pitviper (Bothriechis bicolor)

Little Dragons in the Trees

As an added bonus, a move to slightly higher elevations produced a few of the team's second target: Matuda's Arboreal Alligator Lizard (Abronia matudai). The brilliant green and brown lizards are surprisingly active and alert compared to other Abronia species, and were quick to bite when captured. The literature reports a green coloration for males, while females are generally brown. All three of the adult specimens appeared to be male, and a somewhat patterned juvenile specimen likely reflected ontogenic color/pattern transition common in many species of Abronia.


An adult Matuda's Arboreal Alligator Lizard © Hector Franz / HERP.MX
An adult Matuda's Arboreal Alligator Lizard
A juvenile <i>Abronia matudai</i> © Hector Franz / HERP.MX
A juvenile Abronia matudai
A juvenile <i>Abronia matudai</i> © Hector Franz / HERP.MX
An adult Abronia matudai

An adult Matuda's Arboreal Alligator Lizard (Abronia matudai)
An adult Matuda's Arboreal Alligator Lizard (<i>Abronia matudai</i>) © Hector Franz / HERP.MX
An adult Matuda's Arboreal Alligator Lizard (Abronia matudai)

With both targets checked off, the team began the long drive north from Mexico's most remote corner. But, if history is any indicator, it won't be long before the team will be back down in the Soconusco region of Chiapas scanning the trees for brilliant pitvipers.





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