The Frog Finder is a unique smartphone guide for searching worldwide frog and toad distributions. It is designed for amphibian researchers, naturalists, educators, hobbyists and anyone interested in knowing species that might occur—or may have once occurred—in specific locations.
The Frog Finder was created by Seungkeol Choe and Jeff Rice, with support from the University of Utah J. Willard Marriott Library in conjunction with the Western Soundscape Archive and the Encyclopedia of Puget Sound at the University of Washington.
The node-based name Anura was defined by Ford and Cannatella (1993) as the last common ancestor of living frogs and all its descendants. According to this definition, †Triadobatrachus is not part of Anura, following Trueb and Cloutier (1991). The late Jurassic fossil †Notobatrachus degiustoi has been considered as having uncertain placement with respect to Anura--possibly the sister-group, possibly not (Cannatella, 1985); or related to Leiopelma (Estes and Reig, 1973). Baez and Basso (1996) placed it as the sister-group of Anura.
†Vieraella herbstii is another relatively complete early Jurassic fossil, but is less well-preserved than †Notobatrachus (Estes and Reig, 1973). The presence of nine presacral vertebrae places it among the basal salientians, but other characters are not sufficiently preserved to permit definitive placement in Anura. A third well-preserved Jurassic fossil taxon, †Eodiscoglossus santonje, has eight presacral vertebrae (Estes and Reig, 1973), and thus is clearly within Anura. †Prosalirusbitis is from the Early Jurassic (Pliensbachian) of Arizona; the putative limbed caecilian †Eocaecilia is from the same formation. It is reputed to be the earliest known "frog" in the sense that it has froglike features such as a urostyle and elongate, anteriorly directed ilia. For more details see the leaf page on †Prosalirus. The monophyly of Anura has rarely been questioned. Griffiths (1963:279) considered Anura to be diphyletic; i.e., Ascaphus and Leiopelma comprised one lineage, and all other frogs a second, "...stemming independently from either different levels of a single proanuran organization or different proanuran stocks." Rocek (1981) considered †Triadobatrachus to be within Anura, and placed Pelobatidae (including only Pelobates and some related fossils), and somewhat tentatively, Pipidae, †Palaeobatrachidae, and Rhinophrynidae, in Archaeosalientia. †Triadobatrachus and remaining anurans were included in Neosalientia. The character distinguishing the two groups is a median dermal bone, the interparietal (Reinbach, 1939), which Rocek homologized with the median extrascapular of the osteolepiform fish †Eusthenopteron. The interparietal is found in Pelobates and some fossil relatives, but not in any pipoid frogs. Milner (1988) provided a cogent review of the interpretation of this dermal element.
In a study of tetrapod phylogeny, Hedges et al. (1990) analyzed 123 phylogenetically informative sites from 18S ribosomal RNA of 21 tetrapods, including 4 salamanders, 4 caecilians, and 1 species each from Bufonidae, Discoglossidae, Hylidae, Leptodactylidae, Microhylidae, Pelobatidae, and Sooglossidae. Bootstrap analyses using both maximum-parsimony and neighbor-joining algorithms did not support the monophyly of Anura, Caudata, or Gymnophiona, but a monophyletic Amphibia was supported with a bootstrap value of 100%. Hedges and Maxson (1993) and Hillis et al. (1993) presented analyses of anuran relationships based on DNA sequence data from the mitochondrial and nuclear ribosomal genes, respectively.
Hedges et al. (1990) also analyzed 35 variable sites from 28S rRNA of four species of frogs, from Discoglossidae, Hylidae, Pelobatidae, and Pipidae. Bootstrap analysis of maximum parsimony trees yielded a monophyletic Anura, but with no resolution among the four taxa. The neighbor-joining analysis indicated a sister-group relationship between the discoglossid and pipid, and between the bufonid and hylid, but the bootstrap value for both of these nodes was less than 50%. Neither analysis yielded a monophyletic Amphibia.
Hay et al. (1995) is the most comprehensive molecular systematics treatment of the relationships among the families of amphibians. Their neighbor-joining tree yielded a monophlyletic Anura, Caudata, and Gymnophiona.
Archaeobatrachians have generally included discoglossoids, pipoids and pelobatoids (Duellman, 1975; Reig, 1958). As discussed on other pages, the synapomorphies of Bombinanura and Pipanura collectively demonstrate that "Archaeobatrachia" is paraphyletic. The informal term archaeobatrachian is a convenient term for anurans that are not part of Neobatrachia.
Bombinanura, a node-based name, was defined by Ford and Cannatella (1993) to be the most recent common ancestor of living Bombinatoridae and Discoglossanura, and all its descendants. Synapomorphies of Bombinanura include fusion of the halves of the sphenethmoid, eight presacral vertebrae, absence of the m. epipubicus, and absence of the caudalipuboischiotibialis muscle (Cannatella, 1985). Subclades of Bombinanura include Bombinatoridae and Discoglossanura.
Discoglossidae and Discoglossoidea
Most analyses of molecular sequence data have placed Alytes, Discoglossus, Bombina, and Barbourula in a clade, to which the name Discoglossidae has been applied. In contrast, Ford and Cannatella (1993) listed derived morphological features that would require paraphyly of this group , and they recognized both Discoglossidae (for Alytes and Discoglossus) and Bombinatoridae (for Bombina and Barbourula). A synthesis of the two datasets has not been attempted. There are apparently no published synapomorphies for "Discoglossidae," and the dissimilarity of Alytes and Discoglossus, on one hand, and Bombina on the other, has often been noted (e.g., Lanza et al., 1976), suggesting a deep divergence between the two lineages. Griffiths (1963) stated that the diagnostic feature of Discoglossidae (sensu lato) was a triradiate sternum. However, this feature is also present in Leiopelma. The similarity can be interpreted either as shared plesiomorphy between Leiopelma and Discoglossidae, or a derived feature that unites Leiopelma more closely to Discoglossidae than to Ascaphus.
The node-based name Pipanura was proposed by Ford and Cannatella (1993) for the most recent common ancestor of living Mesobatrachia + Neobatrachia, and all its descendants. The subordinal name Ranoidei was coined for this clade by Sokol (1977), but that name was re-assigned to a less inclusive taxon by Dubois (1983, 1984). Sokol's (1977) use of this name was unfortunate because the informal name, ranoid, is homonymous with the widely used name Ranoidea.
Synapomorphies include a sinistral spiracle in the larvae (a characteristic feature of Orton's Type 4 tadpole), absence of free ribs in adults, torsion in the carpal elements, the presence of vocal sacs, and fusion of the trigeminal and facial ganglia (Cannatella, 1985; Sokol, 1975).
The name was applied to the node that is the common ancestor of living Megophryidae, Pelobatidae, and Pelodytes. Synapomorphies of Pelobatoidea include the presence of a palatine process of the maxilla and ossification of the sternum into a bony style (Cannatella, 1985). Duellman and Trueb (1986) listed the presence of a dorsal gap in the cricoid ring as a synapomorphy for this clade. However, there is no gap in Scaphiopus, Spea, Pelobates (except for the smallest species, P. fuscus), or several megophryids; at best, the presence of a dorsal gap would be an ambiguous synapomorphy. Relationships among the living pelobatoids are an unresolved trichotomy of Megophryidae, Pelobatidae, and Pelodytes.
Pipoidea was defined by Cannatella and Ford (1993) to be the most recent common ancestor of living Pipidae + Rhinophrynidae, and all its descendants. Pipoidea is diagnosed by several distinctive synapomorphies, including the absence of mentomeckelian bones (see comments below on †Palaeobatrachidae), absence of lateral alae of the parasphenoid, fusion of the frontoparietals into an azygous element, greatly enlarged otic capsules, and a tadpole with paired spiracles, and lacking beaks and denticles (Orton Type 1 tadpole). Clades of Pipoidea include Pipidae, †Palaeobatrachidae, some unplaced fossil "pipids," and Rhinophrynidae.
The new stem-based name Pipimorpha was defined by Ford and Cannatella (1993) to be those taxa that are more closely related to living Pipidae than to living Rhinophrynus. Pending a more detailed assessment of the relationships of †Palaeobatrachidae, Pipidae, and the fossil "pipids," we consider †Palaeobatrachidae, †Thoraciliacus,†Cordicephalus, †Saltenia, †Shomronella, and †Eoxenopoides to be part of Pipimorpha.
Ford and Cannatella (1993) applied the name Mesobatrachia to the node that is the most recent common ancestor of the living Pelobatoidea and Pipoidea. This relationship was based on synapomorphies discussed by Cannatella (1985). Mesobatrachia as proposed by Laurent (1979) was a paraphyletic group. Cannatella (1985) first applied the name to a clade. Synapomorphies reported for Mesobatrachia included closure of the frontoparietal fontanelle by juxtaposition of the frontoparietal bones, partial closure of the hyoglossal sinus by the ceratohyals, absence of the taenia tecti medialis, and absence of the taenia tecti transversum (Cannatella, 1985; Sokol, 1981).Most other previous taxonomies, and recent molecular phylogenetic analyses, have placed the Pelobatoidea as the sister-group to Neobatrachia, rather than to Pipoidea. Thus, the Mesobatrachia as formerly proposed is not monophyletic, and therefore no longer recognized.
Amphibians are a unique group of vertebrates that are distributed across the globe. Sadly, nearly one-third of the world’s over 7,300 species are threatened. Frogs are the most speciose of three orders of amphibians, which also includes salamanders and worm-like caecilians.
Use these cards to help you focus on the key traits and behaviors that make different frogs species unique. Drawings, photographs and notes or recordings of vocalizations are a great way to supplement your field notes as you explore the diversity of these amazing animals.
"Some species in the dry forests of South America secrete a waxy coating to protect themselves from drying out." (Morell 2001)
"The lipid contents of these organelles appear to consist of stacks of flattened lipid vesicles (Landmann, 1986, 1988) comprising primarily glycosphingolipids, free sterols and phospholipids, which are precursors of the stratum corneum lipids (Fig. 4). Eventually, the lipid contents of the organelles are secreted into the extracellular domain, where they are further processed into compact lipid bilayers that occlude the extracellular spaces among adjacent and overlapping corneocytes (Fig. 4), a condition that has been likened to a 'bricks-and-mortar' organization (Elias, 1983; Elias and Menon, 1991). It has been proposed that acylglucosylceramides serve as molecular 'rivets' to promote flattening and stacking of lipid vesicles that subsequently fuse edge-to-edge to produce lamellae comprising paired bilayers that are stacked parallel to the skin surface (Engström et al., 2000; Wertz, 2000). These form multiple lamellar sheets with smooth surfaces shown in freeze-fracture studies. In this manner, the extracellular lipids form a continuous domain throughout the stratum corneum and function as the principal barrier to water diffusion (Elias and Friend, 1975; Fig. 2)." (Lillywhite 2006:217) Learn more about this functional adaptation.
Virginia Morell. 2001. The fragile world of frogs. National Geographic. 199(5): 106-23.
"Although anurans have a three-chambered heart, little mixing of oxygenated and unoxygenated blood occurs because of the separation of atrial inflow and outflow." (Fowler and Miller 2003:22) Learn more about this functional adaptation.
"As far as I know, all extracellular mucuses and gels are secreted in concentrated form and then take up water--a conspicuous example is the jelly mass in which the eggs of a frog are suspended. When swollen, the mass is typically larger than the volume of the gravid female. Slime production by hagfish, according to John Gosline, provides an even more spectacular case." (Vogel 2003:444) Learn more about this functional adaptation.
Steven Vogel. 2003. Comparative Biomechanics: Life's Physical World. Princeton: Princeton University Press. 580 p.
Barcode of Life Data Systems (BOLD) Stats Specimen Records:28763 Specimens with Sequences:33511 Specimens with Barcodes:21388 Species:2618 Species With Barcodes:2449 Public Records:9310 Public Species:947 Public BINs:1794