Agkistrodon bilineatus

Subspecies:

Agkistrodon bilineatus bilineatus (GÜNTHER, 1863)
Agkistrodon bilineatus howardgloydi CONANT 1984
Agkistrodon bilineatus lemosespinali SMITH & CHISZAR 2001
Agkistrodon bilineatus russeolus GLOYD 1972

Author: GÜNTHER Year 1863

Common Name:
English: Cantil, Mexican Moccasin
German: Mokassinschlange




young A. bilineatus female at HerpaWorld

Distribution:

Mexico (Tamaulipas, coastal areas of S Sonora, Sinaloa, Nayarit, Jalisco, Morelos, Colima, Michoacan, Guerrero, Oaxaca, N Campeche, Yucatan, Quintana Roo),
N Belize, Guatemala (pacific coast), Honduras, Nicaragua, El Salvador,
NW Costa Rica

Terra typica: Pacific coast of Guatemala.

Comment: Venomous!

See color plate 79 in VILLA et al. 1988 and Trutnau 2001. Trutnau (2001) also presents a map with all subspecies. Agkistrodon bilineatus howardgloydi is illustrated in Penner (2001). Agkistrodon bilineatus taylori has been elevated to species status by PARKINSON et al. (2000) based on mtDNA sequences.

References:
Bolanos, R., & MONTERO, J. R. 1971. Agkistrodon bilineatus Günther from Costa Rica. Rev. Biol. Trop. 16 [1970]: 277-279.
Burger,W.L. & Robertson,W.B. 1951. A new subspecies of the Mexican moccasin, Agkistrodon bilineatus. Univ. Kans. Sci. Bull. 34: 213-218
Calmonte, T. 1982. Agkistrodon bilineatus taylori - ein selten importierter Dreieckskopf aus Mexiko. Herpetofauna 4 (20): 26-27
Campbell, J.A. & Lamar, W.W. 1989. The Venomous Reptiles of Latin America. Comstock Publishing/Cornell University Press, Ithaca
Castro-Frankco, R. & Guadalupe Bustos Zagal, M. 2004. Additional records and range extensions of reptiles from Morelos, México. Herpetological Review 35 (2): 196-197
Conant, R. 1984. A new subspecies of the pit viper Agkistrodon bilineatus (Reptilia: Viperidae) from Central America. Proc. Biol. Soc. Wash. 97: 1-135.
Gloyd and Conant 1943. A synopsis of the American forms of Agkistrodon (Copperheads and Moccasins) Bull. Chicago Acad. Sci. 7: 147-170
Gloyd, H. K. 1972. A subspecies of Agkistrodon bilineatus (Serpentes: Crotalidae) on the Yucatán Peninsula, México. Proc. Biol. Soc. Washington 84: 327-334.
Günther. A. 1863. Third account of new species of snakes in the collection of the British Museum. Ann. Mag. Nat. Hist. (3) 12: 348 - 365
Hoevers, L., & HENDERSON, R. W. 1974. Additions to the herpetofauna of Belize (British Honduras). Milwaukee Publ. Mus. Contr. Biol. Geol. No. 2, 6 pp.
McDiarmid,R.W.; Campbell,J.A. & Touré,T.A. 1999. Snake species of the world. Vol. 1. Herpetologists’ League, 511 pp.
Parkinson,C.L. 1999. Molecular systematics and biogeographical history of pitvipers as determined by mitochondrial ribosomal DNA sequences. Copeia 1999 (3): 576-586
Parkinson,C.L., Zamudio, K.R. & Greene, H.W. 2000. Phylogeography of the pitviper clade Agkistrodon: historical ecology, species status and conservation of cantils. Mol. Ecology 9: 411-420
Penner, J. 2001. Der grösste Schlangenzoo Lateinamerikas - ein Praktikum im “World of Snakes” Grecia, Csota Rica. Elaphe 9 (4): 81-85
Porras, L.W. & Solórzano, A. 2006. Die Schlangen Costa Ricas. Reptilia (Münster) 11 (5): 20-27
Porras, L.W. & Solórzano, A. 2006. Costa Rica’s venomous snakes. Reptilia (GB) (48): 11-17
Preißler, D. 2004. Alles über Schlangen. Draco 5 (17): 4-21
Schmidt, K. E, & INGER, R. F. 1957. Living Reptiles of the World. Doubleday & Co., 287 pp.
Smith, Hobart M. and David Chiszar 2001. A new subspecies of Cantil (Agkistrodon bilineatus) from Central Veracruz, Mexico (Reptilia: Serpentes). Bull. Maryland Herp. Soc. 37 (4): 130-136
Trutnau, L. 1984. Ein Beitrag zur Kenntnis des Kupferkopfs - Agkistrodon contortrix (LINNAEUS 1766). Herpetofauna 7 (35): 14-26
Trutnau,L. 2001. Einige Bemerkungen zur Biologie, Pflege und Nachzucht der mexikanischen Giftschlangenart Agkistrodon bilineatus GÜNTHER 1863. Herpetofauna 23 (131): 5-14

Hello!
The lemosespinali-subspecies is not valid, well, at least discussed, as far as I know.
The three remaining subspecies produce an intergrade-form in central Guatemala.
The subspecies are treated thoroughly in the work which elevates taylori to species-level (I gotta find the printout since my pdf-loaden harddrive crashed) as well in the current edition of Campbell&Lamar "Venomous Reptiles of the Western Hemisphere".

I do keep one male and five females of the yucatecan form, A.b.russeolus. On yucatán no-one knows the name "cantíl" which is well-used during the remaining distribution-area. The local Mayans call that snake "Uolpoch", sometimes spelled as "Volpoch".
The snakes are pretty young, just having reached maturity last fall. Two of the females had the male each for a fortnight during november/december and should give birth these days....

This is one of the females:

The pic was done by Michael Bollhorn. Thanx for that Michael!

greetings from Hamburg

Sven Vogler

nice specimen Sven...
do you have more picture of them?

thanks for the additional informations...



cheers
Mario

not many. most of them are color-slides (and the scanner went back to the editor-in-chief).
but I could give you the same specimen at about two weeks of age:



and at about three months age:


(The camera was not the best, but I think the pics to be of sufficiently quality)

I can't wait for the new litters. ... as well as a few people. Hello F.Weinsheimer!
I really like these snakes. The fine facial lines are so contrasting. The white markings on the underside are so incredible white. The two-colored eyes.
But....: I never had animals as agressive as these. But "intelligently" agressive, no hysterical biters. Always highly awake - they notice everything.
And: Highly dangerous venom. I know of three reported cases, two horses and one woman. all died within 20 - 30 minutes. When they bite a Mastomys it usually falls down like a puppet-on-a-string when you cut the strins....

greetings from Hamburg

Sven Vogler

At last!
The female pictured above gave birth to at least 5 little devils.
Just prepared everything for sorting them out and counting....



greeting from Hamburg

Sven Vogler

Seven! Those are seven!
Some data:
Mating: 08. De. 2007
Birth: this morning, 12. Jul. 2008
7 young, still in membrane, but poking out.
I've been weighing two with 15,7 g and 19,4 g. (still with egg and a few earth grains)
The mother measures about 70 cm.
The parents were all born in June 2005.

'nuff said!
now I have to party!

greetings from Hamburg

Sven Vogler

Hi Sven,
big congratulations from me - the long waiting find the end!

After the first shedding I´ll visit you and make some digital pictures for you!

Best regards, Michael

Hello Sven!

Big congratulations from me as well! You are totally right, I was waiting a long time for hatchlings from you (since your breeder adults have been hatchlings), so I think I can wait at least for a few weeks until I will come and get some from you. Many thanks in advance! I´m really happy for you and cross my fingers for your second female.

Best wishes

Frank

short update:
all completed their first sheddings from 25th to 27th of july (last weekend).
On saturday I offered some pinkies for the first time. The snakes were interested and investigated the little mice thoroughly but were obviously not hungry. Two of the three which had the pinies overnight at least killed them ...
see what's gonna happen in a few days....

greeting from Hamburg
Sven Vogler

Just as mentioned above Michael Bollhorn came along and did few shots of the little meanies





Thanx for the pix Michael!

Nice Shots

I love the white stripes on the head

How big are they actually?

Greetings,
Markus

Another newbie question:

How dangerous are they really?
I read from "lethal venom", I read from "no known fatalities" - very large scale of opinions in the literature.
Are they aggressive or calm in captivity?

@Markus Gottlieb:
The adults are around 70 cm, The newborn are about 20 cm.
A. b. russeolus is the smallest subspecies of the bilineatus-complex.
The upper pair of white stripes (the thin ones from Rostral to eye) might turn yellow when they grow.

@Günter Leitenbauer:
They are absolutely NOT calm. As I mentioned above when I was telling 'bout them:
They are very aware of every movement in their surrounding, always ready to strike.

concerning the venom:
depending on these snakes' rarity bites seldom occur. About half of the documented deadly cases seem to involve horses, a few sources claim them to be "the 3rd most reason for snakebites in the Yucatán peninsula" (without actual counts....the local Mayans I have interviewed claim to see an Uolpoch only once every few years) and one cited doctor said that he'd lost a reasonable percentage of people bitten by these... ([/i]fide[i] Campbell & Lamar: Vnomous Reptiles of th Western Hemisphere)
I just have to say that the reaction of mice on the venom are frightening enough:
when I fed the first one for the first time with a mouse it bit in a incredible fast movement and the mouse died. Without any further reactions it just dropped dead, just like turning a switch.....
The pinkies which were bitten by the newborn snakes turned to amorphous skin bags filled with red fluid overnight.....
One young snake bit a fuzzy a bit unlucky with only one tooth in the back, it did a few short hops and broke down, bleeding from mouth and nose....

Greeting from Hamburg!

Sven Vogler

sound very scary, a friend of use to have one, she was always alert but never strike, what about their care in captivity,i would like to hear your opinions and personal experieences or recomendations about this ones, I´m hoping to get a pair soon, thanks in advance
pd exellent shot and very very awesome snakes
regards

Hello All

Is here someone breeding russeolus and/or howardgloydi ? Would be interested in CB animals or healthy WC speciemens


Best whishes
Marco

Guenter Leitenbauer wrote:

Another newbie question:

How dangerous are they really?
I read from "lethal venom", I read from "no known fatalities" - very large scale of opinions in the literature.
Are they aggressive or calm in captivity?

I used to keep an adult female that was about 65cm, a very jumpy and nervous snake that twitched when touched by the hook. This is also one of the fastest striker i´ve ever kept. You wouldnt stand a chance to react if they wanted to bite you and you happened to be close enough.
About the venom, from what i have heard its more close the "lethal venom" as you put it.