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-  Anolis krugi

From wikipedia :


Anolis krugi [ 1 ] is a lizard race described by Peters in 1877. Anolis krugi included in the genus Anolis , and family polychrotidae . [ 2 ] [ 3 ] No subspecies are listed in the Catalog of Life . [ 2 ]

Anolis krugi

systematics : 

Domain  : eukaryotes

Kingdom  : animals

Tribe  : Chordates

under Strain : vertebrate 

Class  : reptiles

Order  : Squamata

Family  : polychrotidae

Genus  : Anolis 

Species  : Anolis krugi

scientific name :

§Anolis krugi

AUTHORPeters 1877

synonyms :

Anolis krugi Peters 1877 [ 1 ]

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For the external links , refrences  click here to read the full wikipedia article 

Videos :

Anolis krugi (grass anole, Puerto Rico)

Anolis krugi in Peñuelas

anolis krugi in forest.avi

Puerto Rican anoles

courtesy to :

Wednesday, June 18, 2014

Today is my last day in Puerto Rico, and I wanted to share pictures and post a little bit about each species of anole that I have been collecting on this trip. It’s hard to pick my favorite, but I have to say that collecting Anolis occultus these past few days has been a ton of fun. Our group has lost a lot of sleep, but the results were spectacular!

Anolis occultus :


These lizards are the smallest and most illusive of all of the anoles in Puerto Rico. In fact, you can hardly ever find them in the day and have to use a high lumen flashlight to spot them while they are sleeping at night. This species is one of the ‘twig’ ecomorphs, and is generally found in the canopy hanging off of twigs. They are not dimorphic, meaning, males and females are approximately the same size and shape (with exception of the dewlap size). They have a prehensile tail as well, which helps them hold on the ends of twigs when the wind blows (or a noose is trying to knock them out of a tree). This species has been suggested to form pair bonds based on observations of males and females sleeping in close proximity to one another.

And they squeak when you pick them up!

Anolis gundlachi :


Anolis gundlachi is one of the three species of ‘trunk-crown’ anoles in Puerto Rico. This species is called the yellow-chinned anole because of a distinct yellow patch under their chin. They are also characterized by their beautiful bright blue eyes! This species mostly lives in the montane forests, and is adapted to the cooler environments you find there, making it a species of concern for global warming. However, because of current re-forestation efforts, A. gundlachi actually seem to be thriving at lower elevations!

Anolis cuvieri :


A. cuvieri are the largest anoles in Puerto Rico. These are ‘crown-giant’ anoles that live in the canopy, but come lower to the ground during the day. They are also not very dimorphic, with males only being slightly larger than females (both males and females have large yellow dewlaps). They are usually bright green or green with slight mottling, but there is a rare brown morph that we were lucky enough to find on my first day out! Above on the left is a male who is bright green, and on the right is a female of the rarer brown morph. 


This species is very territorial and aggressive. They won’t bother humans unless you aggravate them, but if you are another lizard, or a potential threat, they will bite, and can inflict lots of damage with their large jaws. They are rare outside of heavily forested areas, which has made their populations a concern in Puerto Rico due to deforestation. We only saw two in El Yunque, but were able to see a very healthy population in Bosque de Cambalache.


Anolis stratulus :


This species may be small compared to some of the species on the island, but were some of the most active - fighting for territories on the rocks and trees. This species has my favorite aggressive display, which involves sticking their tongues out at each other (I posted videos of this in an entry last week). This species are considered ‘trunk-crown’ anoles, but we found them mostly on the rocks and lower on the tree trunks. You can see in the pictures how they could blend in well against the rock face or against a very texturized tree. Top left is an adult female, top right is a picture of both a male (right), and female (left) on a rock.

Anolis pulchellus :


A. pulchellus is one of the most common species of anole in Puerto Rico, especially in the low-lands where there is lots of tall grass and sunshine. These are one of the ‘grass-bush’ ecomorphs on the island. This ecomorph is generally very slender, have long tails, and have stripes that run down the length of their body, camouflaging it well in tall grass. This species is very dimorphic - males are about 20% larger than females, and have a large red and violet dewlap, which you can see in the video above.

Anolis krugi :


Another of the ‘grass-bush’ anoles, A. krugi looks very similar to A. pulchellus, though these species differ in their dewlap color, mottling, and habitat selection. In general, A. krugi are found on grasses in dense-shaded areas, where pulchellus are found in areas with high light. A. krugi has an orange dewlap as well as black mottling on the back (as well as some blue dotting on the back of the neck in males). Like A. pulchellus, this species is also sexually dimorphic, with males similarly about 20% larger than females. Top left is an adult male, top right is an adult female.

Anolis evermanni :


The emerald anole is one of the most elegant anoles on the island. This species is bright green when basking, but can also be mottled (see female on right), as well as completely yellow-ish brown. This species is a ‘trunk-crown’ anole preferring to be higher in the tree for most of the day. This species is also dimorphic, and males are about 30% larger than females, and also have a large yellow dewlap. TAs this species is a trunk-crown, it is generally found in the forested regions, and can be found on a variety of perch sizes. This species, like most species of anoles eats mainly insects, but it has also been found feeding on the nectar! Top left is an adult male, top right an adult female shedding her skin.

Anolis cristatellus :


The crested anole is one of the most common anoles on the island. It is a trunk-ground anole (which means it prefers to perch on tree trunks relatively low to the ground), that is named for the large tail crests on the males. This species is very territorial - it is not uncommon to observe a pair of males displaying or fighting on tree trunks during the day.  Males are 30-40% larger than females, making them the most sexually dimorphic species on the island. While we were sampling, we were surrounded by tons of hatchlings. I managed to grab a few shots of a hatchling that was probably only a week or so old (above right).


These aren’t the only species found on the island, but the other species I was not able to sample. Michele Johnson’s group will be sampling A. cooki, and A. poncensis in the coming weeks, and I’ll post with more info on those species soon!


Hope you all enjoyed this! I’ve had a ton of fun on this trip learning more about each of these species, and meeting great people who are studying them. Stay posted later in July for another trip to the Matanzas River in FL!

Hybridization In Puerto Rican Grass Anoles :


courtesy to :

June 21, 2013  By Jonathan Losos

Anolis krugi, a grass-bush anole from Puerto Rico. Photo from the Reptile Database.

Although closely-related, the Puerto Rican grass-bush anoles Anolis pulchellus and A. krugi are easy to tell apart based on body shape and color and, particularly, dewlap color. Moreover, they are ecologically different, A. pulchellus preferring hotter microhabitats. Their population genetics, however, are not so straightforward. In a paper now available online at The Journal of Evolutionary Biology, Teresa Jezkova, Manuel Leal and Javier Rodríguez-Robles show that there’s some interspecific hanky-panky going on, or at least there was in the past.

Anolis pulchellus. Photo by Emelia Failing

The evidence comes from examination of their mitochondrial DNA. To make a long story short, A. pulchellus in western Puerto Rico seem to have nothing but A. krugi mtDNA. Moreover, there is variation within A. krugi in mtDNA, and this variability is matched geographically by A. pulchellus. That is, western A. pulchellus have the appropriate mtDNA for the A. krugi at their particular locality. The authors suggest that this mitochondrial introgression has occurred many times independently. To make things more complicated, some western A. pulchellus that occur in areas in which A. krugi does not occur—and probably hasn’t for a long time—still have the krugi mtDNA.

And, in case you’re wondering, a pulchellus looks like a pulchellus regardless of its mtDNA. 

Moreover, one of two nuclear genes examined fell out nicely, with one clade containing A. pulchellus and the other containing A. krugi. Go figure! I’ve pasted the abstract below which gives more details and the authors’ hypothesis of how this came to be.



Hybridization and gene introgression can occur frequently between closely related taxa, but appear to be rare phenomena among members of the species-rich West Indian radiation of Anolis lizards. We investigated the pattern and possible mechanism of introgression between two sister species from Puerto Rico, Anolis pulchellus and Anolis krugi, using mitochondrial (ND2) and nuclear (DNAH3, NKTR) DNA sequences. Our findings demonstrated extensive introgression of A. krugi mtDNA (k-mtDNA) into the genome of A. pulchellus in western Puerto Rico, to the extent that k-mtDNA has mostly or completely replaced the native mtDNA of A. pulchellus on this part of the island. We proposed two not mutually exclusive scenarios to account for the interspecific matings between A. pulchellusand A. krugi. We inferred that hybridization events occurred independently in several populations, and determined that k-mtDNA haplotypes harboured in individuals of A. pulchellus can be assigned to four of the five major mtDNA clades of A. krugi. Further, the spatial distribution of k-mtDNA clades in the two species is largely congruent. Based on this evidence, we concluded that natural selection was the probable driving mechanism for the extensive k-mtDNA introgression into A. pulchellus. Our two nuclear data sets yielded different results. DNAH3 showed reciprocal monophyly of A. pulchellus and A. krugi, indicating no effect of hybridization on this marker. In contrast, the two species shared nine NKTR alleles, probably due to incomplete lineage sorting. Our study system will provide an excellent opportunity to experimentally assess the behavioural and ecological mechanisms that can lead to hybridization in closely related taxa.

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