DOCSLIB.ORG

Genetic Variability and Structure of an Isolated Population of Ambystoma

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Genetic Variability and Structure of an Isolated Population of Ambystoma Revised Proof Journal of Genetics © Indian Academy of Sciences DOI 10.1007/s12041-017-0823-6 RESEARCH ARTICLE Genetic variability and structure of an isolated population of Ambystoma altamirani, a mole salamander that lives in the mountains of one of the largest urban areas in the world ROSA-LAURA HEREDIA-BOBADILLA1, OCTAVIO MONROY-VILCHIS1∗, MARTHA M. ZARCO-GONZÁLEZ1, DANIEL MARTÍNEZ-GÓMEZ2, GERMÁN DAVID MENDOZA-MARTÍNEZ2 and ARMANDO SUNNY1 1Centro de Investigación en Ciencias Biológicas Aplicadas, Universidad Autónoma del Estado de México, Instituto literario # 100, Colonia Centro, CP 50000 Toluca, Estado de México, México 2Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana Xochimilco, Calz. Del Hueso 1100, Col. Villa Quietud, 04960 México, México ∗ For correspondence. E-mail: [email protected]; [email protected]. Received 17 October 2016; revised 8 December 2016; accepted 6 January 2017 Abstract. Amphibians are globally threatened by habitat loss and fragmentation; species within the order Ambystoma are not the exception, as there are 18 species of mole salamanders in México, of which 16 are endemic and all species are under some national or international status of protection. The mole salamander, Ambystoma altamirani is a microendemic species, which is distributed in central México, within the trans-Mexican volcanic belt, and is one of the most threatened species due to habitat destruction and the introduction of exotic species. Nine microsatellite markers were used to determine the genetic structure, genetic variability, effective population size, presence of bottlenecks and inbreeding coefficient of one population of A. altamirani to generate information which might help to protect and conserve this threatened species. We found two genetic subpopulations with significant level of genetic structure (FST = 0.005) and high levels of genetic variability (Ho = 0.883; He = 0.621); we also found a small population size (Ne = 8.8), the presence of historical (M = 0.486) and recent bottlenecks under IAM and TPM models, with a low, but significant coefficient of inbreeding (FIS =−0.451). This information will help us to raise conservation strategies of this microendemic mole salamander species. Keywords. population genetics; conservation genetics; microsatellites; microendemic species; threatened species. Introduction the surrounding area of Mexico city, where this species live, are severely changed, leading to a severely degraded Amystoma altamirani is an endemic mountain mole sala- habitat fragmented by agriculture and urban settlements mander that lives in small, permanent streams which flows (Lemos-Espinal et al. 1999; Griffiths et al. 2004; Frías- in the high mountains in central Mexico in Pinus and Álvarez et al. 2008; Contreras et al. 2009; Lemos-Espinal Abies religiosa forests. This species occur in isolated pop- et al. 2016; Sunny et al. 2017) and the wooded areas are ulations of the valley of Mexico, in the trans-Mexican subjected to illegal logging (FAO 2006; Ellis and Porter- volcanic belt (TMVB), at altitudes from 2700 to 3450 masl Bolland 2008; Becker et al. 2016), stream pollution and (meters above sea level) (Lemos-Espinal 2003; Shaffer sedimentation (Shaffer et al. 2008). Also, local people tend et al. 2008). The Abies–Pinus forest and the streams in to eat molesalamanders (Casas-Andreu et al. 2004)and Electronic supplementary material: The online version of this article (doi:10.1007/s12041-017-0823-6) contains supplementary material, which is available to authorized users. Revised Proof Rosa-Laura Heredia-Bobadilla et al. introduce trout, carp and tilapia farms that predate and Materials and methods compete with mole salamanders, even in protected natu- ral areas (Lemos-Espinal et al. 1999, 2016; Griffiths et al. Study site and population sampling 2004; Frías-Álvarez et al. 2008; Shaffer et al. 2008; Con- treras et al. 2009; Farías-Álvarez et al. 2010). This has Population samplings were done from January to June eliminated the species from many streams, and many pop- 2014 in a small stream (±1km2) surrounded by induced ulations showed a severe decline of >50% over the last and alpine grassland near a Pinus hartwegii and Abies three generations (Shaffer et al. 2008). The environmen- religiosa forest and some rural houses in Tlazala, state ◦ ◦ tal vulnerability score of A. altamirani is 13, in a range of of México (19 31 31 N, 99 26 09.52 W with an altitude 3–19; this score positions it between medium and high vul- of 3185 masl; figure 1). This site is a private land, where nerabilities, primarily because of its restricted geographic ecotourism activities are carried out, along with trout and ecological distributions (Wilson et al. 2013; Lemos- farming, subsistence logging, and cattle and sheep grazing. Espinal et al. 2016). Therefore, this species is protected by We obtained 96 tissue samples, the mole salamanders were Mexican law under the ‘Special Protection’ category and found in small ponds (transects) of ∼ 40 cm in depth and the IUCN categorized this species as endangered (Shaffer 1–2 m of area separated by ∼10−20 m. There were multi- et al. 2008; Semarnat 2010). The isolated and fragmented ple trapping locations along the rivers, so that the sampling populations by a matrix of agriculture and urbanization, areas were chosen for the differences in the microenviron- can be considered islands in terms of genetic variability, mental characteristics of the river; we found four types of gene flow and landscape connectivity (Kim et al. 1998; substrates (mud, gravel, bedrock and sand). To represent Sunny et al. 2014a). The fragmentation of the habitat all maturity stages of A. altamirani in the data, tissue was and the introduction of exotic species at the landscape obtained from both adults and larvae. Sampling of larvae scale may reduce connectivity among amphibian popula- was limited (≥10%) and efforts were made to avoid sam- tions leading to fragmentation and isolation, which could pling siblings. The individuals were collected with fishing reduce gene flow and increase the loss of genetic variability net and we sampled 2 mm2 of tail clips. This methodology through genetic drift and increase the chance of inbreeding is a low-impact method that does not affect the survival (Lande 1998; Frankham et al. 2002, 2005; Beebee and Grif- or growth of the mole salamanders (Arntzen et al. 1999; fiths 2005; Storfer et al. 2009; Hedrick 2011), bottlenecks Polich et al. 2013); tissue was preserved in 90% ethanol and ◦ and diseases (Frankham et al. 2005) and the probability then frozen at −20 C until processed. All mole salaman- of local extinctions (Newman and Tallmon 2001; Johans- ders were released immediately at the point of capture. Our son et al. 2006). Habitat change affects the populations of study received the approval of the ethics committee of Uni- amphibians and reptiles more than other vertebrate taxa versidad Autónoma del Estado de México (3047-2011E). (Jäggi and Baur 1999; Woinarski and Ash 2002; Anadón et al. 2006; Castellano and Valone 2006; Ribeiro et al. DNA extraction and microsatellite amplification 2009; Sunny et al. 2014a, 2015, 2017), owing to their small home ranges, high philopatry and low vagility (Huey Genomic DNA was extracted using a commercial kit 1982; Ribeiro et al. 2009). For these reasons, amphibians (Vivantis GF-1 tissue DNA extraction kit); we used nine are a high priority vertebrate group for which conser- microsatellite loci (At 52.2, At 52.10, At 52.143, At 60.3, vation strategies must be carried out (Cushman 2006; At 52.115, At 52.6, At 52.34, A5 52.20 and At 52.1) Storfer et al. 2009; Allentof and O’Brien 2010; Nori et al. specifically developed for Mexican Ambystomas and fol- 2015). Therefore, we studied the genetic variability and lowed published protocols (Parra-Olea et al. 2007)for structure, effective population size, inbreeding and genetic amplification. PCR reactions were performed in a Techne bottlenecks of a population of A. altamirani in a highly thermocycler, amplified products were multiplexed on an disturbed habitat. The study area is subjected to pres- ABI Prism3730xl and sized with a ROX-500 as an inter- sures, such as illegal logging introduction of exotic species nal size and then scored using PEAK SCANNER V1.0 such as trout, human settlements and pollution of the (Applied Biosystems, Foster City, USA) software; allele streams. Under this scenario, we expected that there will sizes were measured and rounded with the software TAN- be high genetic structure patterns induced by landscape DEM (Matschiner and Salzburger 2009). modification and because we studied a small population, isolated and subjected to anthropogenic pressures, this population would present low levels of genetic variability Microsatellite analysis and effective population size, and presence of inbreeding and genetic bottlenecks. This information will help us to Potential scoring errors: Typing errors and the presence raise conservation strategies of this microendemic mole of null alleles were determined using the Micro-Checker salamander species. software (Van Oosterhout et al. 2004). Revised Proof Population genetics of Ambystoma altamirani Figure 1. (a) Map of Mexico showing in gray, the TMVB and in dark gray, the State of Mexico. (b) State of Mexico showing in white, Isidro Fabela. (c) The sampling site in Tlazala, Isidro Fabela. Genetic structure: The Structure 2.3.4 software (Pritchard within populations based on FST values, using 999 per- et al. 2000) was used to
Load more

Recommended publications
  • Identification of Mutant Genes and Introgressed Tiger Salamander
    www.nature.com/scientificreports OPEN Identification of Mutant Genes and Introgressed Tiger Salamander DNA in the Laboratory Axolotl, Received: 13 October 2016 Accepted: 19 December 2016 Ambystoma mexicanum Published: xx xx xxxx M. Ryan Woodcock1, Jennifer Vaughn-Wolfe1, Alexandra Elias2, D. Kevin Kump1, Katharina Denise Kendall1,5, Nataliya Timoshevskaya1, Vladimir Timoshevskiy1, Dustin W. Perry3, Jeramiah J. Smith1, Jessica E. Spiewak4, David M. Parichy4,6 & S. Randal Voss1 The molecular genetic toolkit of the Mexican axolotl, a classic model organism, has matured to the point where it is now possible to identify genes for mutant phenotypes. We used a positional cloning– candidate gene approach to identify molecular bases for two historic axolotl pigment phenotypes: white and albino. White (d/d) mutants have defects in pigment cell morphogenesis and differentiation, whereas albino (a/a) mutants lack melanin. We identified in white mutants a transcriptional defect in endothelin 3 (edn3), encoding a peptide factor that promotes pigment cell migration and differentiation in other vertebrates. Transgenic restoration of Edn3 expression rescued the homozygous white mutant phenotype. We mapped the albino locus to tyrosinase (tyr) and identified polymorphisms shared between the albino allele (tyra) and tyr alleles in a Minnesota population of tiger salamanders from which the albino trait was introgressed. tyra has a 142 bp deletion and similar engineered alleles recapitulated the albino phenotype. Finally, we show that historical introgression of tyra significantly altered genomic composition of the laboratory axolotl, yielding a distinct, hybrid strain of ambystomatid salamander. Our results demonstrate the feasibility of identifying genes for traits in the laboratory Mexican axolotl. The Mexican axolotl (Ambystoma mexicanum) is the primary salamander model in biological research.
    [Show full text]
  • The Origins of Chordate Larvae Donald I Williamson* Marine Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom
    lopmen ve ta e l B Williamson, Cell Dev Biol 2012, 1:1 D io & l l o l g DOI: 10.4172/2168-9296.1000101 e y C Cell & Developmental Biology ISSN: 2168-9296 Research Article Open Access The Origins of Chordate Larvae Donald I Williamson* Marine Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom Abstract The larval transfer hypothesis states that larvae originated as adults in other taxa and their genomes were transferred by hybridization. It contests the view that larvae and corresponding adults evolved from common ancestors. The present paper reviews the life histories of chordates, and it interprets them in terms of the larval transfer hypothesis. It is the first paper to apply the hypothesis to craniates. I claim that the larvae of tunicates were acquired from adult larvaceans, the larvae of lampreys from adult cephalochordates, the larvae of lungfishes from adult craniate tadpoles, and the larvae of ray-finned fishes from other ray-finned fishes in different families. The occurrence of larvae in some fishes and their absence in others is correlated with reproductive behavior. Adult amphibians evolved from adult fishes, but larval amphibians did not evolve from either adult or larval fishes. I submit that [1] early amphibians had no larvae and that several families of urodeles and one subfamily of anurans have retained direct development, [2] the tadpole larvae of anurans and urodeles were acquired separately from different Mesozoic adult tadpoles, and [3] the post-tadpole larvae of salamanders were acquired from adults of other urodeles. Reptiles, birds and mammals probably evolved from amphibians that never acquired larvae.
    [Show full text]
  • Axolotl Care Compiled by Dayna Willems, DVM
    Axolotl Care Compiled by Dayna Willems, DVM Brief Description Axolotls (Ambystoma mexicanum) are a Mexican species of aquatic salamander that has rapidly come into the pet trade due to their hardy nature and unusual appearance. Axolotls are amphibians meaning that they do go through several stages of metamorphosis before reaching their adult form. Axolotls are unusual in that their adult/reproductive stage is the same as the juvenile aquatic stage. This is called neoteny and is often considered a “backward” step in evolution. Axolotls are closely related to Tiger Salamanders which do eventually morph into a terrestrial form. It should be noted that under extreme stress, an axolotl may morph into a terrestrial form, but their life is significantly shortened. Being amphibians, axolotls do not tolerate handling well and must stay in the water to breathe. They have sensitive skin and can absorb toxins from the water or your skin. Should you need to transport your axolotl or move it for tank maintenance, do not use a net. Nets can cause abrasions in your axolotl’s sensitive skin or damage the gills. Instead use a plastic cup to scoop your axolotl out of the enclosure. Lifespan Providing the correct care to your axolotl will ensure a long life. Average life expectancy is around 10 years, but reports have been found of axolotls living into their 20’s. Their adult size is around 10 to 12 inches; which they typically reach within the first year of their life. Sexing Axolotls reach sexual maturity when they are around 6-8 inches long.
    [Show full text]
  • FROGLOG Newsletter of the IUCN /SSC Amphibian Specialist Group (ASG)
    Ambystoma opacum byTim Halliday ISSN 1026-0269 FROGLOG Newsletter of the IUCN /SSC Amphibian Specialist Group (ASG) December 2006, Number 78 amphibian species entering ponds individuals. Computer assisted Impacts of from clearcut versus forest habitats pattern-matching software clearcutting on across years. Of the 149,756 developed specifically for A. amphibians amphibians that were captured opacum by Lex Hiby of after 20 years and included in our analysis, 17 of Conservation Research Ltd. of forest re- 18 species at all ponds in all years (Cambridge, UK) drastically establishment migrated to ponds in significantly reduced the number of photo By: Don R. Church, Henry M. smaller numbers from the clearcut comparisons that needed to be Wilbur and Larissa Bailey habitats than from the forest made by eye. Individuals had habitats associated with each overall high fidelity to their point of The long-term impacts of forestry pond. The one exception was the entry to and exit from a pond within practices on amphibian spring peeper, Hyla crucifer, which and across years. populations remain uncertain. was caught in significantly larger Using recently developed multi- Several studies in eastern North numbers entering from the clearcut state mark-recapture methods America have previously shown habitat at each pond. These (Bailey et al., 2004) and that clearcutting of upland forests results raised the question: Why multimodel inference (Burnham & results in a reduction in the number exactly do fewer amphibians Anderson, 2002) we found that of pond-breeding amphibians that migrate to ponds from clearcut survival probabilities within both migrate to breeding sites. habitats after 20 years of forest breeding and non-breeding However, in general, deciduous reestablishment? The answer to seasons varied among years, forests of eastern North America this question has important populations, and between habitats.
    [Show full text]
  • Hearing Sensitivity and the Effect of Sound Exposure on the Axolotl (Ambystoma Mexicanum) Amy K
    Western Kentucky University TopSCHOLAR® Masters Theses & Specialist Projects Graduate School 5-2015 Hearing Sensitivity and the Effect of Sound Exposure on the Axolotl (Ambystoma Mexicanum) Amy K. Fehrenbach Western Kentucky University, [email protected] Follow this and additional works at: http://digitalcommons.wku.edu/theses Part of the Biology Commons, and the Cell and Developmental Biology Commons Recommended Citation Fehrenbach, Amy K., "Hearing Sensitivity and the Effect of Sound Exposure on the Axolotl (Ambystoma Mexicanum)" (2015). Masters Theses & Specialist Projects. Paper 1496. http://digitalcommons.wku.edu/theses/1496 This Thesis is brought to you for free and open access by TopSCHOLAR®. It has been accepted for inclusion in Masters Theses & Specialist Projects by an authorized administrator of TopSCHOLAR®. For more information, please contact [email protected]. HEARING SENSITIVITY AND THE EFFECT OF SOUND EXPOSURE ON THE AXOLOTL (AMBYSTOMA MEXICANUM) A Thesis Presented to The Faculty of the Department of Biology Western Kentucky University Bowling Green, Kentucky In Partial Fulfillment Of the Requirements for the Degree Master of Science By Amy K Fehrenbach May 2015 2 I dedicate this thesis to my parents, Paul and Debbie Fehrenbach. Your love and support have made all of this possible, and I could not have done it without you. Thank you for everything. ACKNOWLEDGMENTS I would first like to thank Dr. Michael Smith for mentoring and advising me throughout my time at WKU. His guidance, work ethic, and positive attitude have made this project possible. I would also like to thank my committee members Dr. Steve Huskey and Dr. Wieb van der Meer for their feedback and patience during this process.
    [Show full text]
  • Invited Review the Phylogenetic Odyssey of the Erythrocyte. IV. The
    Histol Histopathol (1997) 12: 147-170 Histology and 001: 10.14670/HH-12.147 Histopathology http://www.hh.um.es From Cell Biology to Tissue Engineering Invited Review The phylogenetic odyssey of the erythrocyte. IV. The amphibians C.A. Glomski, J. Tamburlin, R. Hard and M. Chainani State University of New York at Buffalo, Department of Anatomy and Cell Biology, School of Medicine, Buffalo, New York, USA Summary. Amphibians mani fes t permanently nucleated , Introduction oval. flatte ned , biconvex ery throcytes. These cell s demonstrate a cytoskeleton which is responsible for their H e moglo bin is a n unique, a nc ie nt respirato ry morphogeneti c conversion from a sphere to an ellipse me ta ll o -pig m e nt w hose s pec ia li zed func ti o ns a nd imparts to the ir cellular m ass revers ibility of a re d e mo ns tra bly e nha nced by it s m ic ro ­ traumati c deformati o n. The class Amphibia has the environmentali zati on in a passive-flowi ng, circulating largest of all erythrocytes attaining volumes greater than cell as opposed to free physical solution in the plasma as 10,000 fe mto lite rs in the Amphiuma. The la rge seen at the in vertebrate level (Glomski and Tamburlin, dimensions re fl ect evolutionary processes, genomic size, 1989). The degree of its polymeri zati on, association with plo id y a nd the re lative size of o the r somati c cell s. interactive enzyme syste ms, and the structure o f it s Conversely, the ery throcyte count a nd he mog lobin globin chains confe r upon the compound a spectrum of concentrat io n of these spec ies are low.
    [Show full text]
  • The Axolotl Genome and the Evolution of Key Tissue Formation Regulators Sergej Nowoshilow1,2,3†*, Siegfried Schloissnig4*, Ji-Feng Fei5*, Andreas Dahl3,6, Andy W
    OPEN ArtICLE doi:10.1038/nature25458 The axolotl genome and the evolution of key tissue formation regulators Sergej Nowoshilow1,2,3†*, Siegfried Schloissnig4*, Ji-Feng Fei5*, Andreas Dahl3,6, Andy W. C. Pang7, Martin Pippel4, Sylke Winkler1, Alex R. Hastie7, George Young8, Juliana G. Roscito1,9,10, Francisco Falcon11, Dunja Knapp3, Sean Powell4, Alfredo Cruz11, Han Cao7, Bianca Habermann12, Michael Hiller1,9,10, Elly M. Tanaka1,2,3† & Eugene W. Myers1,10 Salamanders serve as important tetrapod models for developmental, regeneration and evolutionary studies. An extensive molecular toolkit makes the Mexican axolotl (Ambystoma mexicanum) a key representative salamander for molecular investigations. Here we report the sequencing and assembly of the 32-gigabase-pair axolotl genome using an approach that combined long-read sequencing, optical mapping and development of a new genome assembler (MARVEL). We observed a size expansion of introns and intergenic regions, largely attributable to multiplication of long terminal repeat retroelements. We provide evidence that intron size in developmental genes is under constraint and that species-restricted genes may contribute to limb regeneration. The axolotl genome assembly does not contain the essential developmental gene Pax3. However, mutation of the axolotl Pax3 paralogue Pax7 resulted in an axolotl phenotype that was similar to those seen in Pax3−/− and Pax7−/− mutant mice. The axolotl genome provides a rich biological resource for developmental and evolutionary studies. Salamanders boast an illustrious history in biological research as the 14.2 kb) using Pacific Biosciences (PacBio) instruments (Supplementary animal in which the Spemann organizer1 and Sperry’s chemoaffinity Information section 1) to avoid the read sampling bias that is often found theory of axonal guidance2 were discovered.
    [Show full text]
  • Exotic Animal Ownership and Regulations Amending New Jersey Species Restriction, Bans, and Requirements
    Exotic Animal Ownership and Regulations Amending New Jersey Species Restriction, Bans, and Requirements Tag Words: exotic animals; ownership Authors: Chris Dipiazza, Julie Haas with Julie M. Fagan, Ph.D. Summary The purpose of this whole project was to attempt to make a difference or at least get a better understanding of the issues surrounding the banning of owning certain kinds of exotic pets. Julie’s original concern went back to her not being able to transport her pet bird and lizard, Bearded Dragon, under her seat with her on a plane. Instead the airline insisted they be kept in storage beneath which can be extremely stressful especially for the bird, which is an African Gray Parrot, a species known for being extremely intelligent but also at the same time, very sensitive. My (Chris) issue had more to do with private responsible owners not being legally allowed to own certain species that really have no obvious reason for being unfit pets in the state of New Jersey. The species I was particularly focused on were salamanders belonging to the genus, amystoma. Their common names are the Tiger Salamander and the Axolotl. The first action we took to gain more information about transportation regulations and ownership regulations was to make a trip over to Hamburg, Pennsylvania to attend a reptile show, http://www.hamburgreptileshow.com/ , which is held there every other month. Reptile shows are gatherings for pet reptile enthusiasts to congregate, buy, trade, sell or just observe captive reptiles and other exotic pets. An educational seminar was also given on exotic animals, their ownership requirements, and their regulations.
    [Show full text]
  • WHAT IS the STATUS of the MEXICAN AXOLOTL? H.I. GRIFFITHS and D.H
    British Herpetological Society Bulletin, No. 26, 1988. WHAT IS THE STATUS OF THE MEXICAN AXOLOTL? H.I. GRIFFITHS and D.H. THOMAS School of Pure and Applied Biology, University of Wales College of Cardiff, P 0 Box 915, Cardiff CF1 3TL The Mexican Axolotl Ambystoma mexicanum Shaw 1789, is most certainly the most widely used research species of the urodela, having generated in excess of 3300 publications by 1971 alone (Smith and Smith, 1971). Despite this the natural history of the Axolotl and of the other Mexican members of the Ambystomatidae is almost totally unknown. Brandon (1970) undertook a short field study of A. dumerilli at Lake Patzcuaro in the mountains of Michoacan, but other than this field data for most species appears to consist of little more than records of captures made by Feder, Lynch, Shaffer and Wake (1982). The situation for A. mexicanum is surprisingly little better. The species has been recorded from only two localities (Lake Xochimilco and Lake Chalco in the Valley of Mexico) though it may also have been previously present in the channels joining Lake Zumpango and Lake Texcoco (Frost, 1985; Fig. 1). First hand accounts of the species habitat are few and far between. Velasco made a series of observations at the site in October 1879 (Kranz, Smith and Smith, 1971) and interestingly recorded that the species did metamorphose at Lake Xochimilco in late October/early November. Hans Gadow also visited the site (Gadow, 1903) but his account, though giving a little information about Lake Xochimilco, falls short of real field observation. Feder et al.
    [Show full text]
  • Axolotls Are Aquatic Animals and Need to Live in Water at All Times for Their Skin to Stay Moist and Gills to Function Properly
    albino, white albino, white with black eyes, and spotted varieties. HOUSING YOUR AXOLOTL: Axolotls are aquatic animals and need to live in water at all times for their skin to stay moist and gills to function properly. The best place to house an axolotl is a large fish tank placed indoors in a shady area out of the sun. TANK SIZE: When choosing a tank, consider that axolotls can grow to 25-35 cm in length and need sufficient space to move. The accepted minimum would be a 45 cm long aquarium for one adult axolotl. You can keep a group of axolotls together as long as there is enough A Guide to Keeping space and places to hide. However, axolotls chase and eat anything smaller than themselves so watch out for any fish, young AXOLOTLS axolotls or other animals placed in the tank. The tank does not have to be very deep as axolotls mainly sit on the bottom and slowly AXOLOTLS walk around the tank. They occasionally come to the surface to take a breath of air. Axolotls are also called Mexican Walking Fish. They are however not fish, but belong to the SUBSTRATE: family of Amphibians like frogs, toads and The best substrate to go into the bottom of salamanders. They are the juvenile form of a the tank is sand, e.g. children’s play sand from Bunnings or Mitre Ten, as axolotls will try to salamander but do not metamorphose into the swallow anything that fits into their mouths. adult stage. They retain their gills and fins Swallowed pieces of gravel can cause throughout their life and never leave their intestinal blockages and death.
    [Show full text]
  • Dermal Lesions, Hemorrhage, and Limb Swelling in Laboratory Axolotls
    March 2003 Lab Animal Volume 32, No. 3 WHAT’S YOUR DIAGNOSIS Thomas M. Donnelly, DVM, Column Editor What’s your diagnosis? Dermal Lesions, Hemorrhage, and Limb Swelling in Laboratory Axolotls Submitted by Elizabeth W. Davidson, PhD, James K. Jancovich, MS, Sandra Borland, BA, Meg Newberry, BS, and Jill Gresens, ALAT, BS The axolotl (Ambystoma mexicanum) is a eggs, juveniles have unsurpassed regenera- large salamander native to Lake tive capabilities, adults have large nerves, Xochimilco, Mexico. It belongs to the and genetically defined mutants are avail- group of salamanders known as mole sala- able. All axolotls used in research come manders. Other members of this group from the Indiana University Axolotl include the tiger salamander (Ambystoma Colony (IUAC; http://www.indiana.edu/ tigrinum) and the spotted salamander ~axolotl/), which was founded in 1957. (Ambystoma maculatum). Axolotls exhibit There we breed axolotls ~10 months of the neoteny, which is the retention of juvenile year and distribute tens of thousands of FIGURE 1. Dermal pustules with diffuse petechial hemorrhaging on the vent of a characteristics in adult stages of life. Adult embryos, larvae, and adult axolotls. white axolotl. axolotls display arrested transformation of We house adult axolotls individually in selected features such as gills, despite the 1 gallon bowls or in groups of three or four colony had undergone a similar disease sexual maturation of their gonads. They in plastic tubs, ~10 inches x 18 inches x 6 outbreak in the summer of 1995. Not only keep their feathery external gills and tailfin inches deep (25 cm x 46 cm x 15 cm).
    [Show full text]
  • Sperm Storage in Spermathecae of the Great Lamper Eel, Amphiuma Tridacfyhm (Caudata: Amp Hi U Midae)
    JOURNAL OF MORPHOLOGY 230:79-97 (1996) Sperm Storage in Spermathecae of the Great Lamper Eel, Amphiuma tridacfyhm (Caudata: Amp hi u midae) DAVID M. SEVER, J. SEAN DOODY, COURTNEY A. REDDISH, MICHELLE M. WENNER, AND DON R. CHURCH Department of Biology, Saint Mary's College, Notre Dame, Indiana 46556 (D.M.S., C.A.R., M.M. W.); Department of Biological Sciences, Southeastern Louisiana University, Hammond, Louisiana 70402 (J.S.D., D.R.C.) ABSTRACT The spermathecae of ten female Amphiuma tridactylum were examined by light and electron microscopy during the presumed mating and ovipository seasons (March-August) in Louisiana. Spermathecae were simple tubuloalveolar glands in the dorsal wall of the cloaca. Six of the ten specimens were vitellogenic, and all of these specimens contained sperm in their sperma- thecae and had secretory activity in the spermathecal epithelium. Two nonvitel- logenic females also had sperm in their spermathecae and active epithelial cells, whereas the other nonvitellogenic females lacked stored sperm and secretory activity in the spermathecae. In specimens storing sperm from March-May, the sperm were normal in cytology, and secretory vacuoles were contained within the epithelium. In the August sample, however, evidence of sperm degradation was present, and secretory material had been released into the lumen by an apocrine process. We therefore hypothesize that the spermathecal secretions function in sperm degeneration. Q 1996 Wiley-Liss, Inc. The Amphiumidae consists of three spe- of A. tridactylum and described these glands cies of Amphiuma, elongate, fossorial sala- in A. means and A. phloleter. In addition, manders with reduced limbs and one exter- Sever ('gla, '94) reported on the phylogeny nal gill slit, a paedomorphic character of the spermathecae and other cloacal glands (Duellman and Trueb, '86).
    [Show full text]