DOCSLIB.ORG

A Different Type of Amphibian Mesoderm Morphogenesis in Ceratophrys Ornata

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A Different Type of Amphibian Mesoderm Morphogenesis in Ceratophrys Ornata Development 117, 307-317 (1993) 307 Printed in Great Britain © The Company of Biologists Limited 1993 A different type of amphibian mesoderm morphogenesis in Ceratophrys ornata Susan M. Purcell* and Ray Keller Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA *Present address: Department of Pharmacology, School of Medicine, University of Washington, Seattle, WA 98195, USA SUMMARY Ceratophrys ornata, the Argentinean horned frog, has a Prospective somitic tissue ingresses first from two lat- significantly different pattern of early morphogenesis eral zones, followed by ingression of prospective noto- than does the most studied amphibian, Xenopus laevis. chord from the medial zone and tailbud mesoderm from Time-lapse videomicroscopy, scanning electron the circumblastoporal zone. This is unlike X. laevis, in microscopy, histological sections and lineage tracers which no cells with constricted apices are present on the have shown that, in C. ornata, some prospective noto- dorsal surface of the archenteron, nor do any cells chord, somite and tailbud mesoderm cells leave the sur- ingress into the deep mesodermal layers from the sur- face epithelium of the archenteron by ingression. After face layer. gastrulation, SEM reveals cells with constricted apices and a bottle shape in three zones on the archenteron roof and in a fourth zone around the blastopore. Key words: mesoderm, notochord, ingression, amphibian INTRODUCTION from X. laevis. Since Keller published the fate map of X. laevis in 1975, some have speculated that Vogt’s and Pas- It was long thought that early and fundamental processes teels’ fate maps may be incorrect (Løvtrup, 1975; of development such as gastrulation, were conserved fea- Nieuwkoop and Sutasurya, 1976). tures of development since their alteration would have To begin resolving this issue, we have analyzed gastru- repercussions on later events. But it appears that gastrula- lation movements and mesoderm morphogenesis in the tion and mesoderm morphogenesis are in fact highly vari- Argentinean horned frog, Ceratophrys ornata, a species of able processes (Ballard, 1981). In the amphibians, an impor- frog not closely related to X. laevis (Duellman and Trueb, tant issue is the tissue fates and organization of the marginal 1986). The embryo of C. ornata differs from that of X. zone. There has been a controversy for decades over laevis in having prospective mesoderm in the surface layer whether the origin of the mesoderm is the same in all anuran at the gastrula stage. These findings are significant for amphibians (frogs and toads) (Løvtrup, 1966, 1975; understanding the cellular mechanisms of morphogenesis Nieuwkoop and Sutasurya, 1976, 1979; Hanken, 1986). and pattern formation in anurans, and for understanding the Some ectoderm of the marginal zone is induced to form evolution of morphogenetic processes that occur in early mesoderm by the subblastoporal endoderm during the late vertebrate embryogenesis. blastula stages in amphibian embryos (Nieuwkoop, 1969; Sudarwati and Nieuwkoop, 1971). The marginal zone invo- lutes through the blastopore during gastrulation, internaliz- ing the endodermal and mesodermal layers. In the anuran MATERIALS AND METHODS Xenopus laevis, only prospective endoderm and ectoderm are found on the surface of the pregastrula embryo. The Obtaining and handling of embryos mesoderm forms in the deep layers and remains there Fertilized Ceratophrys ornata eggs were obtained from Bob’s throughout gastrulation (Nieuwkoop and Florshütz, 1950; Happy Fish (Rt 4 Box 605, Woodland, CA 95695) and were kept Sudarwati and Nieuwkoop, 1971; Keller, 1975, 1976). in 15% Steinberg’s solution or 15% modified Barth’s solution. Eggs range in size from 1.5 to 2.0 mm in diameter. The outer Keller’s fate map of X. laevis is different from earlier fibrous jelly coat and the vitelline envelope were removed with fate maps of other anurans. Vogt’s fate map of Bombina - sharpened forceps, and the inner jelly coat was removed by soak- tor (Bombina) (1929) and Pasteels’ map of Discoglossus ing in a solution of 3.5% cysteine hydrochloride at pH 7.9 for 2 (1942) show surface mesoderm in the marginal zones of to 5 minutes. All manipulations were done in 35 mm plastic Petri these anuran embryos, implying that these species differ dishes, some with a base of 2% agarose. 308 S. M. Purcell and R. Keller Staging of embryos Staging of C. ornata is according to the table of normal devel- opment for this species (Purcell and Brothers, J. A., unpublished data). Stage 10: early gastrula, formation of the blastopore lip. Stage 13: blastopore closing, 1/5 original diameter. Stage 13.5: slit blastopore. Stage 14: neural plate formation. Stage 15-16: neural folds closing. Stage 17: neural tube closed, anterior somitic furrows formed. Stage 18: All somitic furrows of the body axis formed, tailbud formed. Videomicroscopy Explants of the dorsal side of the embryo were made at stage 13 and 13.5, by a modification of the method of Wilson et al. (1989), but unlike their dissection, here the epithelium of the roof of the archenteron was left intact (Fig. 1). The explants were made and cultured in 100% modified Danilchik’s solution, which prevents healing and curling up in culture and supports normal develop- ment (Keller et al., 1985). Explants in this medium may live for 3-4 days, well past the end of recording at about 24 hours after fertilization. Images of explants were recorded for 9 hours, until Fig. 1. Explant technique for videomicroscopy of the archenteron tailbud stage. Recordings were made using a Zeiss upright com- roof and for SEM is shown. For videomicroscopy, stage 14 pound microscope with a Nikon 4´ or a Zeiss 10´ plan objective, embryos were cut between the lateral edge of the archenteron roof low angle epi-illumination and a DAGE-MTI 81 high resolution and the ventral yolk mass. The dorsal piece was removed, turned video camera. Images were processed by averaging 32 frames and upside down and placed under a coverslip for filming such that the using contrast control features of an Image One video image epithelium of the archenteron could be seen. The coverslip was processor (Universal Imaging, Media, PA), and recorded on a positioned using vacuum grease. For SEM preparations, embryos Panasonic TQ-2028F optical memory disk recorder (OMDR). were fixed first at different stages and then the explants were made as shown before dehydration. bp, blastopore, a, anterior, d, dorsal. Scanning electron microscopy Embryos were fixed in a solution of 2% glutaraldehyde in 0.10 M sodium cacodylate buffer (pH 7.4) for 12 hours at 4°C. the surface epithelium and ingress (Figs 2,3). The bound- Embryos were cut with a microscalpel to expose the archenteron aries between zones I and II are substantive in that cells roof; ventral halves were discarded (Fig. 1). Some embryos were were not seen to cross this boundary, although cell cut transversely or obliquely to expose the deep cell layers. rearrangement was minimal in any case. Cells in the medial Embryos were then critical-point dried with liquid CO2, mounted on stubs with silver paint, coated with platinum by standard meth- and lateral zones first constrict their apices (arrows, Fig. ods, and viewed on an ISI-DS130 scanning electron microscope 2A,B), and then leave the epithelial layer (Fig. 2A,C). This with an accelerating voltage of 15 kV. happens rapidly, occurring within a few hours at room tem- perature. In the recordings, only cells with tightly con- Histology stricted apices leave the epithelium, and all constricted cells Embryos were placed in Smith’s fixative for 12 hours at 4°C, eventually disappear. The high correlation between these dehydrated using an ethanol series, embedded in Paraplast using two cell behaviors suggests that apical constriction may be Histosol and cut into 10 mm sections. Sections were stained with necessary for ingression to occur. Cells with apical con- giemsa stain, and mounted with Permount. Embryos were fixed striction appear dark due to concentration of apical pigment at gastrula (stage 10) through tailbud (stage 18). granules into a smaller area. At the completion of ingres- Vital dye marking sion, the non-ingressing cells of the lateral archenteron sur- face meet at the midline. These cells do not constrict their Vital dye marking of the surface cells was done using Nile blue dye in agarose chips (Keller, 1975), which were placed up against apices (arrowhead, Fig. 2A,C). This process was observed the embryo for 15 seconds. This is long enough for the surface in four recordings, each using an embryo from a different cells under the chip to take up the dye. Control embryos were dis- batch, with no significant differences between them. sected at stage 13, before any ingression occurred, to be sure only Fig. 3 shows tracings made from the video recording surface cells were taking up the Nile blue. Embryos were marked shown in Fig. 2, with selected cells outlined and numbered at stage 10 and dissected at stage 15,16,17 or 18 to locate the dye to illustrate the points made above. The two lateral zones marks. of ingression are shaded. The medial zone and the non- ingressing cells are unshaded. In the first 25 minutes of the recording (Fig. 3A,B), cells in the lateral zones, numbered RESULTS 1,2,3,5,6,18 and 21, disappear. None of the cells in the medial zone disappears. Cells in one of the lateral zones Cell movements recorded by time-lapse have ingressed completely, and the other lateral zone is sig- videomicroscopy nificantly smaller. Videorecordings of the dorsal surface of the archenteron In the second 25 minutes of the recording (Fig. 3B,C), and the blastopore region in explants from stage 13 to stage cells in the other lateral zone complete their ingression, 18 show that apically constricted cells in four zones leave leaving only cells in the medial zone, which have not fin- Mesoderm morphogenesis in C.
Load more

Recommended publications
  • Pedal Luring in the Leaf-Frog Phyllomedusa Burmeisteri (Anura, Hylidae, Phyllomedusinae)
    Phyllomedusa 1(2):93-95, 2002 © 2002 Melopsittacus Publicações Científicas ISSN 1519-1397 Pedal luring in the leaf-frog Phyllomedusa burmeisteri (Anura, Hylidae, Phyllomedusinae) Jaime Bertoluci Departamento de Zoologia, Universidade Federal de Minas Gerais. Caixa Postal 486, Belo Horizonte, MG, Brazil, 31270-901. E-mail: [email protected]. Keywords - Phyllomedusa burmeisteri, Phyllomedusinae, Hylidae, Anura, pedal luring, prey capture, feeding behavior. Luring behavior as a strategy of prey cap- the frog was maintained in a 60 × 30 × 37-cm ture has evolved independently in several glass terrarium containing soil and a bromeliad. squamate lineages, including pygopodid lizards On the fourth day of acclimation at 2300 h and (Murray et al. 1991), and boid (Murphy et al. under dim light, pedal luring was observed in 1978, Radcliffe et al. 1980), viperid (Greene response to offering the frog an individual adult and Campbell 1972, Heatwole and Dawson cricket (Orthoptera); the same observations were 1976, Henderson 1970, Sazima 1991), elapid made the next night. During the next three days, (Carpenter et al. 1978), and colubrid snakes the frog fed on domestic cockroaches (Sazima and Puorto 1993). Bavetz (1994) (Blattaria), but pedal luring was not observed in reported pedal luring related to predation in these circumstances. Larval mealworms ambystomatid salamanders. In anurans, this (Tenebrio sp.) also were offered to the frog, but feeding behavior has been described only for the always were refused. terrestrial leptodactylid frogs Ceratophrys Phyllomedusa burmeisteri is a sit-and-wait calcarata (Murphy 1976) and C. ornata predator that typically perches with its hands (Radcliffe et al. 1986). Pedal luring apparently and feet firmly grasping the substrate while does not occur in the terrestrial leptodactylids searching for prey.
    [Show full text]
  • Ceratophrys Cranwelli) with Implications for Extinct Giant Frogs Scientific Reports, 2017; 7(1):11963-1-11963-10
    PUBLISHED VERSION A. Kristopher Lappin, Sean C. Wilcox, David J. Moriarty, Stephanie A.R. Stoeppler, Susan E. Evans, Marc E.H. Jones Bite force in the horned frog (Ceratophrys cranwelli) with implications for extinct giant frogs Scientific Reports, 2017; 7(1):11963-1-11963-10 © The Author(s) 2017 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Originally published at: http://doi.org/10.1038/s41598-017-11968-6 PERMISSIONS http://creativecommons.org/licenses/by/4.0/ 19th of April 2018 http://hdl.handle.net/2440/110874 www.nature.com/scientificreports OPEN Bite force in the horned frog (Ceratophrys cranwelli) with implications for extinct giant frogs Received: 27 March 2017 A. Kristopher Lappin1, Sean C. Wilcox1,2, David J. Moriarty1, Stephanie A. R. Stoeppler1, Accepted: 1 September 2017 Susan E.
    [Show full text]
  • Micro-CT Imaging of Anuran Prey in Ceratophrys Ornata (Anura: Ceratophryidae)
    SALAMANDRA 51(2) 209–211 30 June 2015 ISSNCorrespondence 0036–3375 Correspondence To have a frog in the throat: micro-CT imaging of anuran prey in Ceratophrys ornata (Anura: Ceratophryidae) Thomas Kleinteich Christian-Albrechts-Universität zu Kiel, Funktionelle Morphologie und Biomechanik, Am Botanischen Garten 9, 24118 Kiel, Germany e-mail: [email protected] Manuscript received: 21 May 2014 Accepted: 11 July 2014 by Alexander Kupfer Frogs of the genus Ceratophrys are sit-and-wait preda- solution as a contrast agent, following the protocol suggest- tors that feed on a variety of different prey types, includ- ed by Metscher (2009) but with a staining time of three ing spiders, insects, crabs, annelids, but also vertebrates weeks. The specimen was scanned in distilled water. like snakes, lizards, rodents, and other frogs (Duellman & In the resulting micro-CT dataset, I identified a second Lizana 1994). Among amphibian pet keepers, Ceratophrys frog inside the digestive tract of the Ceratophrys ornata spp. are often referred to as pac-man frogs on account of specimen (Figs 1A–C). By using the 3D analysis and visual- their ability to consume vast amounts of prey as well as isation software package Amira 5.4.3, I virtually separated relatively large prey items. Chávez et al. (2011) reported the prey frog from the C. ornata to visualise the prey speci- on an individual of C. cornuta preying upon Leptodactylus men separately for estimating volume measurements. The dydimus (Anura: Leptodactylidae) that was approximate- volume of the C. ornata was 52.26 cm3. From this volume, ly two thirds of its own snout–vent length.
    [Show full text]
  • In Search of the Horned Frog (Ceratophrys Ornata) in Argentina: Complementing Field Surveys with Citizen Science
    Herpetological Conservation and Biology 12(3):664–672. Submitted: 26 May 2017; Accepted: 8 November 2017; Published 16 December 2017. IN SEARCH OF THE HORNED FROG (CERATOPHRYS ORNATA) IN ARGENTINA: COMPLEMENTING FIELD SURVEYS WITH CITIZEN SCIENCE CAMILA DEUTSCH1,4, DAVID BILENCA2,3, AND GABRIELA AGOSTINI1,2 1Conservación de Anfibios en Agroecosistemas, La Plata (1900), Argentina 2Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires Instituto de Ecología, Genética y Evolución de Buenos Aires, Grupo de Estudios sobre Biodiversidad en Agroecosistemas, Buenos Aires, Argentina 3Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina 4Corresponding author, e-mail: [email protected] Abstract.—The Horned Frog (Ceratophrys ornata) is a threatened amphibian that occurs in the temperate grasslands of Argentina, Brazil, and Uruguay. Several populations from Argentina have apparently declined and the species has not been recorded in Uruguay and Brazil for the last 35 y. In Argentina, published occurrence data based on field surveys are scarce, representing only a few localities in the Pampean Region. Considering thatC. ornata is an iconic and distinctive species, we conducted a citizen science program to obtain occurrence data as a complement to field surveys. From 2008 to 2017, we used auditory and visual methods to survey adult C. ornata at 78 localities in the Pampean Region during both spring and summer. From 2015 to 2017, we conducted the citizen science program using online surveys and direct interviews to gather records obtained in the last 10 y. The citizen science program yielded 147 records, representing a nine-fold increase from the 15 records obtained during field surveys.
    [Show full text]
  • Pzg Library News
    1/4 Vernacular Name FROG, ORNATE HORNED (aka: Argentine Horned Frog, Argentine Wide-mouthed Frog, Bell’s Horned Frog, Pacman Frog) GEOGRAPHIC RANGE South America: Argentina, Uruguay, Brazil. HABITAT Burrow in the leafy, muddy vegetation of the tropical forest floor of tropical lowlands. CONSERVATION STATUS • IUCN: Not Yet Assessed (2014). • This species is in significant decline (but at a rate of less than 30% over 10 years) because it is subject to intense persecution: habitat loss (due to agricultural development and housing development) is a major threat, as is water and soil pollution due to agriculture, industry and human settlement. COOL FACTS • The horned frog is named so because it has large fleshy points above its eyes that resemble small horns – e.g., fleshy eyelid “horns”. The "horn" is a triangular prolongation of the edge of the upper eyelid. It is not hard or sharp, as it is only a flap of skin, but perhaps it makes the wide head appear even wider and, therefore, less acceptable to predators. • The horned frogs' most prominent feature is its mouth, which accounts for roughly half of its overall size. These frogs are often called "mouths with legs" because the mouth appears to be the entire front half of the body. Their huge mouths and ravenous appetites have earned them the pet trade nickname “Pac Man frogs”. • One extraordinary characteristic that these amphibians possess is their innate ability to devour organisms larger than their own body size. They feed on frogs, lizards, other reptiles, mice and large insects. • Like all amphibians, horned frogs have porous skin and respond quickly to changes in the environment.
    [Show full text]
  • Frog Eat Frog: Exploring Variables Influencing Anurophagy
    Frog eat frog: exploring variables influencing anurophagy G. John Measey1, Giovanni Vimercati1, F. Andre´ de Villiers1, Mohlamatsane M. Mokhatla1, Sarah J. Davies1, Shelley Edwards1 and Res Altwegg2,3 1 Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Stellenbosch, South Africa 2 Statistics in Ecology, Environment and Conservation, Department of Statistical Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa 3 African Climate and Development Initiative, University of Cape Town, South Africa ABSTRACT Background. Frogs are generalist predators of a wide range of typically small prey items. But descriptions of dietary items regularly include other anurans, such that frogs are considered to be among the most important of anuran predators. However, the only existing hypothesis for the inclusion of anurans in the diet of post-metamorphic frogs postulates that it happens more often in bigger frogs. Moreover, this hypothesis has yet to be tested. Methods. We reviewed the literature on frog diet in order to test the size hypothesis and determine whether there are other putative explanations for anurans in the diet of post-metamorphic frogs. In addition to size, we recorded the habitat, the number of other sympatric anuran species, and whether or not the population was invasive. We controlled for taxonomic bias by including the superfamily in our analysis. Results. Around one fifth of the 355 records included anurans as dietary items of populations studied, suggesting that frogs eating anurans is not unusual. Our data showed a clear taxonomic bias with ranids and pipids having a higher proportion of anuran prey than other superfamilies. Accounting for this taxonomic bias, we found that size in addition to being invasive, local anuran diversity, and habitat produced a model that best fitted our data.
    [Show full text]
  • Islet Hormones from the African Bullfrog Pyxicephalus Adspersus (Anura:Ranidae): Structural Characterization and Phylogenetic Implications
    General and Comparative Endocrinology 119, 85–94 (2000) doi:10.1006/gcen.2000.7493, available online at http://www.idealibrary.com on Islet Hormones from the African Bullfrog Pyxicephalus adspersus (Anura:Ranidae): Structural Characterization and Phylogenetic Implications J. Michael Conlon,*,1 Amber M. White,* and James E. Platz† *Regulatory Peptide Center, Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178; and †Department of Biology, Creighton University, Omaha, Nebraska 68178 Accepted March 28, 2000 The African bullfrog Pyxicephalus adspersus is generally amino acid sequence of PP, but not those of the other islet classified along with frogs of the genus Rana in the subfam- hormones, is of value as a molecular marker for inferring ily Raninae of the family Ranidae but precise phylogenetic phylogenetic relationships between early tetrapod species. relationships between species are unclear. Pancreatic © 2000 Academic Press polypeptide (PP), insulin, and glucagon-like peptide (GLP-1) were isolated from an extract of P. adspersus Pancreatic polypeptide (PP) is a 36-amino acid res- pancreas and characterized structurally. A comparison of idue C-terminally ␣-amidated peptide that is synthe- the amino acid sequence of Pyxicephalus PP (APSEPQ- sized primarily in the F cell of the pancreatic islets of 10 20 30 ⅐ HPGG QATPEQLAQY YSDLYQYITF ITRPRF NH2) tetrapods. PP is a member of a family of homologous with those of the known amphibian PP molecules in a max- regulatory peptides that comprises, in addition to PP, imum parsimony analysis generates a single phylogenetic neuropeptide tyrosine (NPY) synthesized in neurons tree in which Pyxicephalus is the sister to the clade compris- of the central and peripheral nervous systems and in ing the members of the genus Rana.
    [Show full text]
  • Anesthetic Considerations for Amphibians Mark A
    Topics in Medicine and Surgery Anesthetic Considerations for Amphibians Mark A. Mitchell, DVM, MS, PhD Abstract The popularity of amphibians in research, zoological exhibits, and as pets is on the rise. With this increased popularity comes a need for veterinarians to develop methods for managing these animals for various diagnostic and surgical proce- dures. For many of these procedures, the provision of anesthesia is a must. Fortunately, there are a number of different anesthetics available to the veterinary clinician for anesthetizing amphibians, including tricaine methanesulfonate, clove oil, propofol, isoflurane, and ketamine. In addition to the variety of anesthetics at our disposal, there is also a wider range of methods for delivering the anesthetics than are generally available for higher vertebrates, including immersion, topical, and intracoelomic routes of delivery. The purpose of this article is to review the different methods that can be used to successfully manage an amphibian patient through an anesthetic event. Copyright 2009 Elsevier Inc. All rights reserved. Key words: amphibian; anesthesia; anesthetic; anuran; monitoring; urodelan mphibians are commonly used in research will respond to an anesthetic the same way. In cases and are popular exhibit animals in zoological in which there is no reference for a particular spe- Acollections. Although they are not as popular cies, special precautions should be taken to mini- as reptiles in the pet trade, they are being presented mize the likelihood of complications. to veterinarians in clinical practice with increased Regardless of the species, success with anesthesia frequency. Because veterinarians are being asked to can be achieved by following a consistent, well- work with these animals, it is important that we planned protocol.
    [Show full text]
  • 5-Minute Guide to Amphibian Disease
    CLINICIAN’S NOTEBOOK 5-minute Guide to Amphibian Disease MADS BERTELSEN ■ GRAHAM CRAWSHAW THE AMPHIBIAN PATIENT IS mammography units. Ultrasonogra- often presented late in the disease phy may help identify coelomic process, and the presenting signs are masses or fluid accumulation and commonly limited to anorexia, weight assist in guiding transcutaneous loss and/or fluid retention. A review aspiration or biopsy. Laparoscopy, of the husbandry and feeding history using a small fiberoptic arthroscope, should be part of any workup. Diag- offers internal visualization. nostic information may be obtained in Careful post mortem examination of a manner similar to that used with diseased specimens followed by other vertebrates, although the small histopathologic examination is crucial size of many patients limits the quan- in diagnosing and treating problems tity and usefulness of diagnostic affecting several animals. Common samples. Mads Bertelsen, DVM clinical manifestations, selected [email protected] Thorough physical examination may differential diagnoses and diagnostic Veterinary Resident reveal fractures, impactions, swellings, options are presented in Table 2. Zoo/Wildlife Medicine and Pathology masses, fluid accumulations or skin Graham Crawshaw, BVetMed, Once a tentative or final diagnosis has and eye abnormalities. Blood can be MRCVS, Dipl ACZM been made, amphibians may be collected from peripheral superficial Toronto Zoo subjected to standard surgical and Scarborough, Ontario veins, but collection is generally more medical treatment. Amphibians have Canada reliable from the heart. Although low metabolic rates but high rates of [email protected] hematologic and biochemical values fluid turnover, placing them between vary and only limited normal values mammals and reptiles in the pharma- are available, analysis of the blood cokinetic spectrum.
    [Show full text]
  • Unrestricted Species
    UNRESTRICTED SPECIES Actinopterygii (Ray-finned Fishes) Atheriniformes (Silversides) Scientific Name Common Name Bedotia geayi Madagascar Rainbowfish Melanotaenia boesemani Boeseman's Rainbowfish Melanotaenia maylandi Maryland's Rainbowfish Melanotaenia splendida Eastern Rainbow Fish Beloniformes (Needlefishes) Scientific Name Common Name Dermogenys pusilla Wrestling Halfbeak Characiformes (Piranhas, Leporins, Piranhas) Scientific Name Common Name Abramites hypselonotus Highbacked Headstander Acestrorhynchus falcatus Red Tail Freshwater Barracuda Acestrorhynchus falcirostris Yellow Tail Freshwater Barracuda Anostomus anostomus Striped Headstander Anostomus spiloclistron False Three Spotted Anostomus Anostomus ternetzi Ternetz's Anostomus Anostomus varius Checkerboard Anostomus Astyanax mexicanus Blind Cave Tetra Boulengerella maculata Spotted Pike Characin Carnegiella strigata Marbled Hatchetfish Chalceus macrolepidotus Pink-Tailed Chalceus Charax condei Small-scaled Glass Tetra Charax gibbosus Glass Headstander Chilodus punctatus Spotted Headstander Distichodus notospilus Red-finned Distichodus Distichodus sexfasciatus Six-banded Distichodus Exodon paradoxus Bucktoothed Tetra Gasteropelecus sternicla Common Hatchetfish Gymnocorymbus ternetzi Black Skirt Tetra Hasemania nana Silver-tipped Tetra Hemigrammus erythrozonus Glowlight Tetra Hemigrammus ocellifer Head and Tail Light Tetra Hemigrammus pulcher Pretty Tetra Hemigrammus rhodostomus Rummy Nose Tetra *Except if listed on: IUCN Red List (Endangered, Critically Endangered, or Extinct
    [Show full text]
  • The Diversity and Evolution of Amphibia: What Are They and Where Did They Come From?
    The diversity and evolution of Amphibia: What are they and where did they come from? Lecture goal To familiarize students with characteristics of the Class Amphibia, the diversity of extant amphibians, and the fossil record of amphibians. Reading assignments: Wells: pp. 1-15, 41-58, 65-74, 77-80 Supplemental readings on amphibian taxa: Wells: pp. 16-41, 59-65, 75-77 Lecture roadmap Characteristics of amphibians Extant amphibian orders Characteristics of amphibian orders and diversity Amphibian fossil record and evolution 1 What are amphibians? These foul and loathsome animals are abhorrent because of their cold body, pale color, cartilaginous skeleton, filthy skin, fierce aspect, calculating eye, offensive smell, harsh voice, squalid habitation, and terrible venom; and so their Creator has not exerted his powers to make many of them. Carl von Linne (Linnaeus) Systema Naturae (1758) What are amphibians? Ectothermic tetrapods that have a biphasic life cycle consisting of anamniotic eggs (often aquatic) and a terrestrial adult stage. Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Amphibia (amphibios: “double life”) Subclass: Lissamphibia Orders: •Anura (frogs) •Caudata (salamanders) •Gymnophiona (caecilians) Amphibia characteristics 1) Cutaneous respiration Oxygen and CO2 Transfer Family Plethodontidae Plethodon dorsalis Gills (larvae, few adult salamanders), 2 Lungs (adults) 2) Skin glands Mucous glands Granular glands 2 Amphibia characteristics 3) Modifications of middle and inner ear Middle ear consists of 2 elements
    [Show full text]
  • Pac Man Frog / Ornate Horned Frog Ceratophrys Ornata
    Pac Man Frog / Ornate Horned Frog Ceratophrys ornata LIFE SPAN: about 6-10 years AVERAGE SIZE: 6-7 inches Males are a bit smaller than females. CAGE TEMPS: 81o HUMDITY: 60-70% * If temp falls below 70° at night, may need supplemental infrared or ceramic heat WILD HISTORY: Native to the rainforests of Brazil, Uruguay and Argentina of South America. PHYSICAL CHARACTERISTICS: The frogs get their common name, “Pac Man Frog” from their round, plump shape and large mouths, which make them resemble the video game character. Their large eyes stay open while they are sleeping. Pac mans are available in many patterns and colors, the most common being yellow and green, with mottled spots/patches. These colors and patterns prove to be perfect camouflage for hiding on the rainforest floor, waiting for prey to happen by. Because of their delicate and porous skin, handling your frog is not recommended. NORMAL BEHAVIOR & INTERACTION: Pac mans are relatively inactive and sedentary. They are beautiful and entertaining pets, but they have no desire to be handled. Handling a pac man frog is very stressful for it and may result in illness. Their skin is very sensitive, being a secondary breathing organ. Some pac mans are diurnal; some are crepuscular. NOTE: DO NOT house Pac Man frogs with others of their species or any other species to prevent cannibalism – your pac man will most likely eat any unsuspecting visitor. Each species may also harbor different parasites/protozoans/bacteria (even a healthy reptile harbors a small amount at all times), which may make each other ill.
    [Show full text]