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Issue: Vol. 25 No. 1: 17 December 2021
Type: Article
Published: 2021-12-17
DOI: 10.11646/bionomina.25.1.1
Page range: 1–20
Abstract views: 1246
PDF downloaded: 1

Just metamorphosed amphibians: imagos or metamorphs?

Institut de Systématique, Évolution, Biodiversité, ISYEB - UMR 7205 - CNRS, MNHN, UPMC, EPHE, Muséum national d’Histoire naturelle, Sorbonne Université, 57 rue Cuvier, CP 30, F-75005, Paris, France
Development growth form metamorphosis larva imago juvenile adult senex metamorph metamorphont heterochrony aneuchrony euchrony neoteny neosystelly argiotrophy ergotrophy

Abstract

The term metamorph for just metamorphosed amphibians appeared surreptitiously in the batrachological literature. It is shown here that this term is linguistically unjustified and conceptually confusing, as it has never been associated with a clear, formal definition stating in particular when does this developmental stage start and end. The use of the term imago for an individual resulting from the last metamorphosis following a larval stage, which exists for insects since 1767 and for amphibians since 1808, is much preferable. For amphibians, the formal definition of this term was given in 1978 as an animal having completed its metamorphosis, before having substantially grown and until the first major ecological event in its life cycle (such as migration, hibernation or aestivation). In amphibians, this stage is followed by a stage juvenile and a stage subadult until the stage adult is reached, which is defined by sexual maturity and ability to reproduce. Given the diversity of developmental modes in the animal kingdom, it would be vain to try to homogenise the terminology of all detailed developmental stages across all groups. However, the possibility to homogenise the use of the term imago throughout zoology for specimens resulting from the ‘last metamorphosis’ (i.e., drastic change not only of form but also in some anatomical structures), whether followed by growth and minor transformations or not, and whether associated with sexual maturity or not, would certainly be worth considering. This would allow to have a few general descriptive terms to designate the main similar, but not homologous, ‘landmarks’ observed in the development of many animals (egg, larva, imago and adult), just like we have a general term (metamorphosis) for ‘similar’ phenomena which are not homologous. This would not prevent specialists of the various zoological groups to have specific terms for more precisely defined ‘stages’ which are proper to these groups.

References

  1. Anonymous [International Commission on Zoological Nomenclature] (1999) International code of zoological nomenclature. Fourth edition. London (International Trust for zoological Nomenclature): i–xxix + 1–306.

  2. Anonymous (2004) Final environmental impact statement for the generic essential fish habitat amendment to the following fishery management plans of the Gulf of Mexico (GOM). Volume 1. Text. Tampa, USA (Gulf of Mexico Fishery Management System): i–xxix + 1.1–1.7 + 2.1–2.144 + 3.1–3.297 + 4.1–4.104 + 5.1–5.6 + 6.1–6.2 + 7.1–7.76 + i–vi + 8.1–8.128 + 9.1–9.126.

  3. Anonymous (2016) Virtual taxonomy. Nature, 535: 323–324. <https://doi.org/10.1038/535323b>.

  4. Abraham, R. K., Pyron, R. A., Ansil, B. R., Zachariah, A. & Zachariah, A. (2013) Two novel genera and one new species of treefrog (Anura: Rhacophoridae) highlight cryptic diversity in the Western Ghats of India. Zootaxa, 3640 (2): 177–189. <https://doi.org/10.11646/zootaxa.3640.2.3>.

  5. Ahlström, E. H. & Ball, O. P. (1954) Description of eggs and larvae of jack mackerel (Trachurus symmetricus) and distribution and abundance of larvae in 1950 and 1951. Fishery Bulletin, 56: 209–245.

  6. Ahlström, E. H. & Moser, H. G. (1976) Eggs and larvae of fishes and their role in systematic investigations and in fisheries. Revue des Travaux de l’Institut des Pêches maritimes, 40: 379–398.

  7. Alberch, P., Gould, S. J., Oster, G. F. & Wake, D. B. (1979) Size and shape in ontogeny and phylogeny. Paleobiology, 5: 296–317. <https://doi.org/10.1017/S0094837300006588>.

  8. Altford, R. A. (1999) 10. Ecology. Resource use, competition, and predation. In: McDiarmid & Altig (1999a): 240–278.

  9. Altig, R. & Johnston, G. F. (1989) Guilds of anuran larvae: relationships among developmental modes, morphologies, and habitats. Herpetological Monographs, 3: 81–109. <https://doi.org/10.2307/1466987>.

  10. Altig, R. & McDiarmid, R. W. (1999) 3. Body plan. Development and morphology. In: McDiarmid & Altig (1999a): 24–51.

  11. Balon, E. K. (1975) Reproductive guilds of fishes: a proposal and definition. Journal of the Fisheries Research Board of Canada, 32: 821–864. <https://doi.org/10.1139/f75-110>.

  12. Barton, [B. S.] (1808) Some account of the Siren lacertina, and other species of the same genus of amphibious animals. In a Letter from Professor Barton, of Philadelphia, to Mr. John Gottlob Schneider, of Saxony. Philadelphia: 1–36, 1 pl.

  13. Bladh, A. J. (1767) Fundamenta entomologiae. Upsaliae (Edman): 1–34.

  14. Bladh, A. J. (1769) CXXXIII. Fundamenta entomologiae. In: C. Linné, Amoenitates Academicae…, Volumen septimum, Holmiae (Laurentii Salvii): 129–159.

  15. Blaustein, A. R., Walls, S. C., Bancroft, B. A., Lawler, J. J., Searle, C. L. & Gervasi, S. S. (2010) Direct and indirect effects of climate change on amphibian populations. Diversity, 2: 281–313. <https://doi.org/10.3390/d2020281>.

  16. Boase, H. S. (1834) Treatise on primary geology; being an examination, both practical and theoretical, of the older formations. London (Longman, Rees, Orme, Brown, Green & Longman): i–xi + 1–399. <https://doi.org/10.5962/bhl.title.30497>.

  17. Bosch, J., Carrascal, L. M., Durán, L., Walker, S. & Fisher, M. C. (2007) Climate change and outbreaks of amphibian chytridiomycosis in a montane area of central Spain; is there a link? Proceedings of the royal Society, (B), 274: 253–260. <https://doi.org/10.1098/rspb.2006.3713>.

  18. Boué, A. (1820) Essai géologique sur l’Écosse. Paris (Courcier): i–x + 1–523, pl. 1–7.

  19. Buendía-Monreal, M. & Gillmor, C. S. (2018) The times they are a-changin’: heterochrony in plant development and evolution. Frontiers in Plant Science, 9 (1349): 1‒8. <https://doi.org/10.3389/fpls.2018.01349>.

  20. Carosi, J. P. de (1783) Sur la génération du silex et du quarz en partie, observations faites en Pologne. Cracovie (Ignace Grebel): [i–xvi] + 1–96, pl. 1–2.

  21. Chandramouli, S. R., Vasudevan, K., Harikrishnan, S., Dutta, S. K., Janani, S. J., Sharma, R., Das, I. & Aggarwal, R. K. (2016) A new genus and species of arboreal toad with phytotelmonous larvae, from the Andaman Islands, India (Lissamphibia, Anura, Bufonidae). Zookeys, 555: 57–90. <https://doi.org/10.3897/zookeys.555.6522>.

  22. Conradie, W., Branch, W. R. & Watson, G. (2015) Type specimens in the Port Elizabeth Museum, South Africa, including the historically important Albany Museum collection. Part 1: Amphibians. Zootaxa, 3936 (1): 42–70. <https://doi.org/10.11646/zootaxa.3936.1.2>.

  23. Das, A., Saikia, U., Murthy, B. H. C. K., Dey, S. & Dutta, S. K. (2009) A herpetofaunal inventory of Barail Wildlife Sanctuary and adjacent regions, Assam, north-eastern India. Hamadryad, 34 (1): 117–134.

  24. Das, I. & Haas, A. (2010) New species of Microhyla from Sarawak: Old World’s smallest frogs crawl out of miniature pitcher plants on Borneo (Amphibia: Anura: Microhylidae). Zootaxa, 2571: 37–52. <https://doi.org/10.11646/zootaxa.2571.1.2>.

  25. Daszak, P., Cunningham, A. A. & Hyatt, A. D. (2003) Infectious disease and amphibian population declines. Diversity and Distributions, 9: 141–150. <https://doi.org/10.1046/j.1472-4642.2003.00016.x>.

  26. De Beer, G. R. (1930) Embryology and evolution. Oxford (Oxford University Press): i–viii + 1–116.

  27. DeGarady, C. & Halbrook, R. (2006) Using anurans as bioindicators of PCB contaminated streams. Journal of Herpetology, 40 (1): 127–130. <https://doi.org/10.1670/30-05N.1>.

  28. Denoël, M., Džukić, G. & Kalezić, M. L. (2005) Effects of widespread fish introductions on paedomorphic newts in Europe. Conservation Biology, 19 (1): 162–170. <https://doi.org/10.1111/j.1523-1739.2005.00001.x>.

  29. Dent, J. N. (1968) Survey of amphibian metamorphosis. In: W. Etkin & L. I. Gilbert (ed.), Metamorphosis, a problem in developmental biology, Amsterdam & New York (Meredith Corporation): 271–311.

  30. Dittrich, C., Drakulić, S., Schellenberg, M., Thein, J. & Rödel, M.-O. (2016) Some like it hot? Developmental differences in yellow-bellied toad (Bombina variegata) tadpoles from geographically close but different habitats. Canadian Journal of Zoology, 94: 69–77. <https://doi.org/10.1139/cjz-2015-0168>.

  31. Downie, J. R., Bryce, R. & Smith, J. (2004) Metamorphic duration: an under-studied variable in frog life histories. Biological Journal of the Linnean Society, 83: 261–272. <https://doi.org/10.1111/j.1095-8312.2004.00387.x>.

  32. Drakulić, S., Feldhaar, H., Lisičić, D., Mioč, M., Cizelj, I., Seiler, M., Spatz, T. & Rödel, M.-O. (2016) Population-specific effects of developmental temperature on body condition and jumping performance of a widespread European frog. Ecology and Evolution, 6: 3115‒3128 + [i‒iii]. <https://doi.org/10.1002/ece3.2113>.

  33. Dubois, A. (1968) Sur deux anomalies de la Grenouille verte (Rana esculenta). Bulletin mensuel de la Société linnéenne de Lyon, 37: 316–320. <https://doi.org/10.3406/linly.1968.6035>.

  34. Dubois, A. (1974) Polydactylie massive, associée à la clinodactylie, dans une population de Rana graeca. Remarques sur la polydactylie faible et la clinodactylie chez Bufo bufo (Amphibiens, Anoures). Bulletin de la Société zoologique de France, 99: 505–521, pl. 1–2.

  35. Dubois, A. (1976) Les Grenouilles du sous-genre Paa du Népal (famille Ranidae, genre Rana). Cahiers népalais - Documents, Paris (CNRS), 6: i–vi + 1–275.

  36. Dubois, A. (1977) Une mutation dominante déterminant l’apparition de diverses anomalies digitales chez Rana temporaria (Amphibiens, Anoures). Bulletin de la Société zoologique de France, 102: 197–213.

  37. Dubois, A. (1978) Les principaux stades de développement significatifs en écologie et en génétique des populations des Amphibiens Anoures. La Terre et la Vie, 32: 453–459.

  38. Dubois, A. (1979) Néoténie et pédogenèse. A propos d’une anomalie du développement chez Bombina variegata (Amphibiens, Anoures). Bulletin du Muséum national d’Histoire naturelle, (4), 1 (A): 537‒546.

  39. Dubois, A. (1987) Neoteny and associated terms. Alytes, ‘1985’, 4 (4): 122–130.

  40. Dubois, A. (2004) Developmental pathway, speciation and supraspecific taxonomy in amphibians. 2. Developmental pathway, hybridizability and generic taxonomy. Alytes, 22 (1–2): 38–52.

  41. Dubois, A. (2008) Drôles d’espèces. Hybridation, perturbations de la méiose et spéciation dans le règne animal: quelques points délicats de terminologie, d’éidonomie et de nomenclature. In: D. Prat, A. Raynal-Roques & A. Roguenant (ed.), Peut-on classer le vivant? Linné et la systématique aujourd’hui, Paris (Belin): 169‒202.

  42. Dubois, A. (2009a) Qu’est-ce qu’une espèce animale? In: Aller à l’espèce: illusion ou nécessité, Mémoires de la Société entomologique de France, 8: 9–48.

  43. Dubois, A. (2009b) Book review. Asexual and metasexual vertebrates. Alytes, 27 (2): 62‒66.

  44. Dubois, A. (2011) Species and ‘strange species’ in zoology: do we need a ‘unified concept of species’? Comptes rendus Palevol, 10: 77–94. <https://doi.org/10.1016/j.crpv.2011.01.002>.

  45. Dubois, A. & Fischer, J.-L. (1975) Un Leptodactyle pentadactyle ectrodactyle (Amphibiens, Anoures). Bulletin mensuel de la Société linnéenne de Lyon, 44: 111–114. <https://doi.org/10.3406/linly.1975.10175>.

  46. Dubois, A. & Henle, K. (2017) Methodological recommendations for studying the causes of anomalies in natural populations of Amphibians. In: Henle & Dubois (2017): 243–260.

  47. Dubois, A. & Vachard, D. (1971) Sur une anomalie pigmentaire de la Grenouille verte (Rana esculenta) et de quelques autres Amphibiens Anoures et Urodèles. Bulletin mensuel de la Société linnéenne de Lyon, 40: 40–52. <https://doi.org/10.3406/linly.1971.2111>.

  48. Duguet, R. & Melki, F. (2003) Les Amphibiens de France, Belgique et Luxembourg. Mèze (Biotope): 1–480.

  49. Embrechts, E. & Reyer, H.-U. (2012) Age and size of hybrid water frogs; the role of genotype and ecology. Herpetologica, 68 (4): 468–481. <https://doi.org/10.1655/HERPETOLOGICA-D-11-00083>.

  50. Fabre, [J.-H.] (1857) Mémoire sur l’hypermétamorphose et les moeurs des Méloïdes. Annales des Sciences naturelles, (4), Zoologie, 7: 299–365, pl. 17.

  51. Fabrezi, M. & Quinzio, S. I. (2008) Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): the effects of heterochronic changes during larval development and metamorphosis. Zoological Journal of the Linnean Society, 154: 752–780. <https://doi.org/10.1111/j.1096-3642.2008.00420.x>.

  52. Finch, C. E. (1990) Longevity, senescence, and the genome. Chicago (The University of Chicago Press):1–938.

  53. Fuiman, L. A. (2002) Chapter 1. Special considerations of fish eggs and larvae. In: L. A. Fuiman & R. G. Werner, Fishery science, The unique contributions of early life stages, Oxford, etc. (Blackwell Science Ltd.): 1–32.

  54. Ganesh, S. R. & Arumugam, M. (2015) Natural history and distribution notes on the Sreeni’s golden frog (Indosylvirana sreeni) in the southern Eastern Ghats, peninsular India. Alytes, 32: 59‒65.

  55. Goedaert, J. (1662) Metamorphoseos et historiae naturalis insectorum. Pars tertia et ultima. Medioburgi (Apud Jacobum Fierensium): [i‒xv] + 1‒159, pl. A‒Y.

  56. Gosner, K L. (1960) A simplified table for staging anuran embryos and larvae with notes on identification. Herpetologica, 16: 183–190.

  57. Gould, S. J. (1977) Ontogeny and phylogeny. Cambridge, Mass. (Belknap Press): i–xvi + 1–501.

  58. Graber, V. (1879) Die Insekten. Zweiter Theil. (Doppelband). Vergleichende Lebens- und Entwicklungsgeschichte der Insekten. II. Hälste. München (R. Oldenbourg): [i–vi] + i–vi + 263–603 + [i–iii].

  59. Greenlees, M. J., Phillips, B. L. & Shine, R. (2010) An invasive species imposes selection on life-history traits of a native frog. Biological Journal of the Linnean Society, 100 (2): 329–336. <https://doi.org/10.1111/j.1095-8312.2010.01432.x>.

  60. Haeckel, E. (1866) Generelle Morphologie der Organismen. Erster Band. Allgemeine Anatomie. Berlin (Georg Kramer): i–xxxii + 1–574, pl. 1–2. <https://doi.org/10.1515/9783110848281>.

  61. Haeckel, E. (1874) Anthropogenie, oder Entwicklungsgeschichte des Menschen. Leipzig (Wilhelm Engelmann): i-xviii + 1–732.

  62. Haeckel, E. (1875) Die Gastrula und die Eifurchung der Thiere. Jenaische Zeitschrift für Naturwissenschaft, 9: 402–508.

  63. Hall, B. K. & Wake, M. H. (1999) The origin and evolution of larval forms. San Diego, USA (Academic Press): 1–425. <https://doi.org/10.1016/B978-012730935-4/50002-X>.

  64. Harris, R. N. (1999) 11. The anuran tadpole. Evolution and maintenance. In: McDiarmid & Altig (1999a): 279–294.

  65. Henle, K. & Dubois, A. (ed.) (2017) Studies on anomalies in natural populations of Amphibians. Mertensiella, 25: 1–260.

  66. Hoff, K. vS., Blaustein, A. R., McDiarmid, R. W. & Altig, R. (1999) 9. Behavior. Interactions and their consequences. In: McDiarmid & Altig (1999a): 215–239.

  67. Hull, D. (1992) Individual. In: E. Fox Keller & E. A. Lloyd (ed.), Keywords in evolutionary theory, Cambridge, MA (Harvard University Press): 180–187.

  68. Hutton, J. (1795) Theory of the earth, with proofs and illustrations. Volume 1. Edinburgh (Creech): i–viii + 1–620, pl. 1–4.

  69. Issel, A. (1916) Prime linee di un ordinamento sistematico delle pietre figurate. Memorie della reale Accademia dei Lincei, (5a), 11 (40): 631–667. [Not seen].

  70. Jeffery, J. E., Bininda-Emonds, O. R. P., Coates, M. I. & Richardson, M. K. (2002a) Analyzing evolutionary patterns in amniote embryonic development. Evolution & Development, 4 (4): 292‒302. <https://doi.org/10.1046/j.1525-142X.2002.02018.x>.

  71. Jeffery, J. E., Bininda-Emonds, O. R. P., Coates, M. I. & Richardson, M. K. (2005) A new technique for identifying sequence heterochrony. Systematic Biology, 54 (2): 230‒240. <https://doi.org/10.1080/10635150590923227>.

  72. Jeffery, J. E., Richardson, M. K., Coates, M. I. & Bininda-Emonds, O. R. P. (2002b) Analyzing developmental sequences within a phylogenetic framework. Systematic Biology, 51 (3): 478‒491. <https://doi.org/10.1080/10635150290069904>.

  73. Jones, P. W., Martin, F. D. & Hardy, J. D., Jr. (1978) Development of fishes of the mid-Atlantic bight. An atlas of egg, larval and juvenile stages. Volume 1. Acipenseridae through Ictaluridae. U.S. Fish and Wildlife Service Biological Services Program, FWS/OBS-78/12: [i–viii] + 1–366.

  74. Kendall, A. W., Jr., Ahlström, E. H. & Moser, H. G. (1984) Early life history stages of fishes and their characters. In: H. G. Moser, W. J. Richards, D. M. Cohen, M. P. Fagay, A. W. Kendall & S. L. Richardson (ed.), Ontogeny and systematics of fishes, Special Publication of the American Society of Ichthyologists and Herpetologists, 1: 11–22.

  75. Kollmann, J. (1884) L’hivernage des larves de Grenouilles européennes et de Tritons. La métamorphose de l’Axolotl mexicain. Comptes rendus de l’Association française pour l’Avancement des Sciences, ‘1883’, 12: 567–570.

  76. Kollmann, J. (1885) Das Ueberwintern von europäischen Frosch- und Tritonlarven und die Umwandlung des mexikanischen Axolotl. Verhandlungen der Naturforschenden Gesellschaft in Basel, ‘1883’, 7: 387–398.

  77. Lathrop, A., Murphy, R. W., Orlov, N. L. & Ho, C. T. (1998) Two new species of Leptobrachium (Anura: Megophryidae) from the central highlands of Vietnam with a redescription of Leptobrachium chapaense. Russian Journal of Herpetology, 5 (1): 51–60.

  78. Lecointre, G., Schnell, N. K. & Teletchea, F. (2020) Hierarchical analysis of ontogenetic time to describe heterochrony and taxonomy of developmental stages. Nature scientific Reports, 10 (19732): [1‒13]. <https://doi.org/10.1038/s41598-020-76270-4>.

  79. Linnaeus, C. (1735) Systema naturae… [Editio prima]. Lugduni Batavorum (de Groot): [i–xii].

  80. Linnaeus, C. (1744) Systema naturae… Editio quarta. Parisiis (Michaelis-Antonii David): [i] + i–xxvi + 1–108, 1 pl.

  81. Linnaeus, C. (1746) Fauna Svecica… [Editio prima]. Lugduni Batavorum (Wishoff & Wishoff): [i–xxix] + 1–411, pl. 1–2.

  82. Linnaeus, C. (1748) Systema naturae… Stockholmiae (Kiesewetteri): [i–iv] + 1–224 + [i–xix], pl. 1–7.

  83. Linnaeus, C. (1751) Animalium specierum… Lugduni Batavorum (Haak): [i–iv] + 1–253 + [i–iii].

  84. Linnaeus, C. (1758) Systema naturae... Editio decima, reformata. Tomus 1. Holmiae (Laurentii Salvii): [i–iv] + 1–824.

  85. Linnaeus, C. (1759) Animalium specierum… Lugduni Batavorum (Theodorum Haak): [i–iv] + 1–256.

  86. Linnaeus, C. (1761) Fauna Svecica. Editio altera, auctior. Stockolmiae (Laurentii Salvii): [i–xlviii] + 1–579, pl. 1–2.

  87. Linné, C. von (1767) Systema naturae. Editio duodecima, reformata. Tomus 1, Pars 2. Holmiae (Laurentii Salvii): 533–1327 + i–xxxiv.

  88. Loewinson-Lessing, F. (1933) Petrography. Third edition. Leningrad (NKTP). [Not seen].

  89. Lyell, C. (1833) Principles of geology, being an attempt to explain the former changes of the earth’s surface, by reference to causes now in operation. Volume 3. London (John Murray): i–xxxii + 1–398 + 1–109, pl.1–5.

  90. Malpighi, M. (1669) Dissertatio epistola de Bombice, societali regiae, Londini ad scientiam naturalem promovendam institutae, dicata. Londini (J. Martyn & J. Alleftry): [i–vi] + 1–100 + [i–iv].

  91. McDiarmid, R. W. & Altig, R. (1990) Description of a bufonid and two hylid tadpoles from western Ecuador. Alytes, 8 (2): 51–60.

  92. McDiarmid, R. W. & Altig, R. (ed.) (1999a) Tadpoles. The biology of anuran larvae. Chicago (The University of Chicago Press): i‒xv + 1–444.

  93. McDiarmid, R. W. & Altig, R. (1999b) 2. Research. Materials and techniques. In: McDiarmid & Altig (1999a): 7–23.

  94. McKnight, B. J. & Jurd, R. D. (1987) The compatibility of Xenopus antibody and homoiothermic complement. Developmental & comparative Immunology, 11 (3): 585–593. <https://doi.org/10.1016/0145-305X(87)90047-4>.

  95. Meegaskumbura, M., Bowatte, G., Manamendra-Arachchi, K. & Meegaskumbura, S. (2011) Amphibian research in Sri Lanka. Froglog, 98: 26‒29.

  96. Minelli, A. (2009) Chapter 7. The life cycle and its evolution. In: Perspectives in animal phylogeny and evolution, Oxford (Oxford University Press): 110‒183. <https://doi.org/10.1093/acprof:oso/9780198566205.003.0007>.

  97. Moler, P. E. (1985) A new species of frog (Ranidae: Rana) from northwestern Florida. Copeia, 1985 (2): 379‒383. <https://doi.org/10.2307/1444847>.

  98. Newman, R. A. (1987) Effects of density and predation on Scaphiopus couchi tadpoles in desert ponds. Oecologia, 71 (2): 301–307. <https://doi.org/10.1007/BF00377299>.

  99. Oresme, N. (1365) Traictie du commencement et première invencion des monnoyes. [Not seen]. Printed by Colard Mansion in 1477 and reprinted by Wolowski (1864).

  100. Owen, T. (1849) On parthenogenesis, or the successive production of procreating individuals from a single ovum. London (John van Voorst): 1–76, pl. 1. <https://doi.org/10.5962/bhl.title.26220>.

  101. Pandian, T. J. (2016) Reproduction and development in Crustacea. Boca Raton, USA (CRC Press): i–xiii + 1–302. <https://doi.org/10.1201/b20080>.

  102. Perrier, E. (1893) Traité de zoologie. Première partie. Zoologie générale. Protozoaires et Phytozoaires. Arthropodes. Paris (Masson): i–vii + 1–1352. <https://doi.org/10.5962/bhl.title.11522>.

  103. Phillips, J. (1837) A treatise on geology. Volume 1. London (Longman, Brown, Green, Longmans & Taylor): i–viii + 1–334.

  104. Réaumur, M. de (1736) Mémoires pour servir à l’histoire des Insectes. Tome 2. Suite de l’histoire des chenilles et des papillons; et l’histoire des Insectes ennemis des chenilles. Paris (Imprimerie Royale): i‒xlviii + 1‒514 + [i‒ii], pl. 1‒40.

  105. Reilly, S., Wiley, E. & Meinhardt, D. (1997) An integrative approach to heterochrony: the distinction between interspecific and intraspecific phenomena. Biological Journal of the Linnean Society, 60: 119‒143. <https://doi.org/10.1111/j.1095-8312.1997.tb01487.x>.

  106. Richards, W. J. (2008) Identification guide of the early life history stages of fishes from the waters of Kuwait in the Arabian Gulf, Indian Ocean. Safat, Kuwait (Kuwait Institute for Scientific Research): [i‒iii] + i‒vii + 1‒329.

  107. Rostand, J. (1955) Les Crapauds, les Grenouilles, et quelques grands problèmes biologiques. Paris (Gallimard): 1–215, 48 pl.

  108. Russell, B. (1953) The cult of ‘common usage’. British Journal for the Philosophy of Science, 3 (12): 303–307. <https://doi.org/10.1093/bjps/III.12.303>.

  109. Semlitsch, R. D. & Wilbur, H. M. (1988) Effects of pond drying time on metamorphosis and survival in the salamander Ambystoma talpoideum. Copeia, 1988 (4): 978–983. <https://doi.org/10.2307/1445721>.

  110. Shulse, C. D., Semlitsch, R. D., Trauth, K. M. & Gardner, J. E. (2012) Testing wetland features to increase amphibian reproductive success and species richness for mitigation and restoration. Ecological Applications, 22 (5): 1675‒1688. <https://doi.org/10.1890/11-0212.1>.

  111. Smith, K. K. (2001) Heterochrony revisited: the evolution of developmental sequences. Biological Journal of the Linnean Society, 73 (2): 169‒186. <https://doi.org/10.1111/j.1095-8312.2001.tb01355.x>.

  112. Smith, K. K. (2002) Sequence heterochrony and the evolution of development. Journal of Morphology, 252 (1): 82‒97. <https://doi.org/10.1002/jmor.10014>.

  113. Snyder, D. E. (1976) Fish larvae—ecologically distinct organisms. In: M. B. Bains (ed.), Ecology and assessment of warmwater streams: workshop synopsis, U.S. Fish and Wildlife Service Biological Report, 90 (5): 20-23.

  114. Tomkeieff, S. I. (1983) Dictionary of petrology. New York (Wiley): 1‒680.

  115. Velhagen, W. A., Jr. (1997) Analyzing developmental sequences using sequence units. Systematic Biology, 46 (1): 204‒210. <https://doi.org/10.1093/sysbio/46.1.204>.

  116. Vences, M. (2004) Amphibians of France, Belgium and Luxembourg. Contributions to Zoology, 73 (4): 323–324. <https://doi.org/10.1163/18759866-07304009>.

  117. Von Baer, K. (1866) Über Prof. Nic. Wagner’s Entdeckung von Larven, die sieht fortpflanzen, Herrn Ganin’s verwandte und ergänzende Beobachtungen und über die Paedogenesis überhaupt. Bulletin de l’Académie impériale des Sciences de St. Pétersbourg, 9: 64‒137, 1 pl.

  118. Waterman, T. (2012) Metabolism and growth. In: The physiology of Crustacea, volume 1, London (Elsevier): 1–688.

  119. Webb, J. F. (1999) Chapter 4. Larvae in fish development and evolution. In: B. K. Hall & M. H. Wake, The origin and evolution of larval forms, San Diego, USA (Academic Press): 109–158. <https://doi.org/10.1016/B978-012730935-4/50005-5>.

  120. Whiteman, H. H. (1994) Evolution of facultative paedomorphosis in salamanders. Quarterly Review of Biology, 69: 205‒221. <https://doi.org/10.1086/418540>.

  121. Wolowski, L. (ed.) (1864) Traictie de la première invention des monnoies de Nicole Oresme, textes français et latin d’après les manuscrits de la Bibliothèque nationale, et Traité de la monnaie de Copernic, Paris (Guillaumin & Co.): i–lxii + i–cxxxix + 1–84.

  122. Youson, J. H. (1988) First metamorphosis. In: W. S. Hoar & D. J. Randall (ed.), Fish physiology, Volume 11, The physiology of developing fish, Part B, Viviparity and posthatching juveniles, San Diego (Academic Press): 135–196. <https://doi.org/10.1016/S1546-5098(08)60214-9>.