Tooth Row Formula Research Articles

A hundred-year-old mystery—the reproductive mode and larval morphology of the enigmatic frog genus Allophryne (Amphibia; Anura; Allophrynidae)

Frogs of the Allophrynidae are an enigmatic family from South America. To date, published information is lacking regarding this group’s reproductive biology and larval morphology. Here, we provide the first detailed description of the reproductive mode, developmental mode, and tadpole morphology for Allophryne ruthveni. We developed a captive breeding and rearing protocol for this species and then conducted a series of observations to describe aspects of its reproductive biology. In captivity, this species exhibits aquatic oviposition, where single eggs are laid ungrouped within a simple jelly capsule and are scattered free in the water column before sinking to develop on benthic substrates. We did not observe parental care nor any parental interactions with eggs post-fertilization. Tadpoles are characterized by an oval body, anteroventral oral disc, a labial tooth row formula of 2(2)/3, and a dextral vent tube. The buccopharyngeal cavity is marked by the presence of two pairs of infralabial papilla and four lingual papillae. Cranial morphology is characterized by the presence of the commissura quadratoorbital. This species possesses an additional slip of the m. rectus cervicis and of the m. levator arcuum branchialium III. We discuss our results in comparison with glassfrogs (Centrolenidae).

Morphological description and life history of the Philippine endemic Limnonectes leytensis Leyte swamp frog in Rogongon, Iligan City, Philippines

Abstract. Flores ABA, Diesmos AC, Nu?eza OM. 2022. Morphological description and life history of the Philippine endemic Limnonectes leytensis Leyte swamp frog in Rogongon, Iligan City, Philippines. Biodiversitas 23: 133-139. The Philippine endemic Limnonectes leytensis (Leyte Swamp Frog) is a widespread species, however, most studies concerning it only focus on adult stages, except for the study on Negros Island. With this, we conducted a study on the morphology and life history of L. leytensis in Rogongon, Iligan City, Philippines. We collected different tadpole stages through opportunistic sampling. Gosner developmental stages 23 to 40 were considered and measured using standard tadpole body morphometrics. Linear regression was used for modeling the relationship between the different morphometrics. Results showed that the tadpoles have a depressed body, dorsolateral eye position and has golden, light to dark brown pigmentation. Apart from this, its mouthpart showed an anteroventral shape, and the labial tooth row formula is 1/2-3, showing a single row in the upper lip and three rows in the lower lip, having the 3rd row half the length of the other two, which is different to that of the results of the past studies which reported that the labial tooth was 1/2:1-1 showing a broken gap in the first tooth row of the lower lip. The analysis revealed a positive relationship between different morphometrics to the total length (body length rs: 0.96; tail length rs: 0.99; musculature height rs: 0.90 and maximum tail height rs: 0.85) with a significance value of <0.001. The data generated from this study will ignite future efforts on tadpole research in the country, given that there are differences found in the tadpoles from different regions.

First description of the tadpole of Kurixalus baliogaster (Inger, Orlov, and Darevsky, 1999) (Anura: Rhacophoridae) from Vietnam, with comments on reproductive biology.

To date, 20 species of Kurixalus Ye, Fei, and Dubois have been described, and all of these species are distributed throughout South and Southeast Asia, from eastern India, throughout Myanmar and the mountainous regions of southern China, to Indochina, western and northern peninsular Thailand, Malaysia, Sumatra, Borneo, and the Philippines (Frost 2021). Descriptions of the tadpoles of only 6 species have been published: K. berylliniris and K. wangi Wu, Huang, Tsai, Li, Jhang, Wu (Wu et al. 2016); K. eiffingeri (Boettger) (Kuramoto Wang 1987); K. idiootocus (Kuramoto Wang) (Kuramoto Wang 1987); K. cf. verrucosus (Boulenger) (Ziegler Vences 2002), and Kurixalus yangi Yu, Hui, Rao, Yang (Humtsoe et al. 2020). A description of the tadpoles of K. baliogaster (Inger, Orlov, Darevsky) is also given in the species description (Inger et al. 1999), but described larvae are assigned tentatively to this species in the published text. Additional studies on the identification of the conspecificity of the described tadpoles with K. baliogaster have not been conducted. Based on the much larger size of the tadpole body (TL up to 40.3 mm), as well as the labial tooth row formula 6(26)/5(1) given by Inger et al. (1999), we concluded that these described tadpoles cannot be larval K. baliogaster and most likely belong to some other species of rhacophorid frogs.

Advertisement call, tadpole morphology, and other natural history aspects of the threatened poison frog Andinobates daleswansoni (Dendrobatidae)

ABSTRACT Describing natural history of species is important because it would allow us to corroborate hypotheses about evolutionary biology and improve conservations plans. We describe the advertisement call, tadpole morphology, and other natural history aspects of the poison frog Andinobates daleswansoni, an endemic threatened species of the Colombian Andes. The advertisement call consists of multiple pulsed notes, with an average dominant frequency of 4052.81 ± 154.93 Hz. This call sounds similar to the call of other Andinobates frogs, but there are clear differences in spectral and temporal features. Tadpoles have a depressed body, low compressed dorsal and ventral tail fins with a rounded tip. The oral disc has a labial tooth row formula of 2(2)/3(1), and a gap in the marginal papillae of the lower lip, whose status as a synapomorphy for the group A. bombetes is discussed. Like other poison frogs, the diet of A. daleswansoni consists of small arthropods (Acari, Hymenoptera, Coleoptera) that individuals capture in leaflitter. We recorded tadpole transport by males to phytotelmata in the Elephant Ear plant (Xanthosoma robustum) which demonstrate that A. daleswansoni has a greater niche breadth for tadpole development than previously recorded. Acoustic interactions and physical fights observed during an agonistic behaviour on the part of two males of A. daleswansoni is similar to those recorded in other poison frogs and possible associated to the occupation of resources such as availability of prey items and places for breeding.

The advertisement call and tadpole of the Ambangulu Puddle Frog (Phrynobatrachus ambanguluensis) (Anura: Phrynobatrachidae) from Tanzania

ABSTRACT The advertisement call, visual signalling, and tadpole of the recently described Phrynobatrachus ambanguluensis are described from the West Usambara Mountains, Tanzania. The call is a soft trill, similar but faster than the call of the sister species P. krefftii from the East Usambaras. Males have been observed flashing the bright yellow vocal sac without calling, which is the second reported non-vocal communication involving flashing the gular pouch in African frogs. The tadpole is generalised, identified by body shape and labial tooth row formula of 2(1)/4.

The tadpole of Odontophrynus barrio Cei, Ruiz, and Beçak, 1982 (Anura: Odontophrynidae): a comparison with the other tadpoles of the genus

We describe the tadpole of Odontophrynus barrioi including external larval features, chondrocranial and cranial musculature, and compare it with the other species of the genus. Tadpoles of O. barrioi at stages 31–37 are about 52.46 mm long. The body is slightly depressed in lateral view and ovoid in dorsal view. Oral disc is emarginate laterally, anteroventral and small with a single row of marginal papillae, a single large dorsal gap, and labial tooth row formula 2(2)/3(1). Despite small interspecific variations, like different labial tooth row formulae, the general aspect of species is quite similar. Although poorly-known yet, the chondrocranium and cranial musculature display some variations within the genus.

Description of tadpoles of the frogs Heterixalus tricolor, H. carbonei and H. luteostriatus (Anura: Hyperoliidae) from western Madagascar.

The genus Heterixalus is endemic to Madagascar. It contains eleven species of small to medium-sized tree frogs that typically inhabit open areas like swamps and rice fields. We describe the larval stages of three sympatric species that occur in western Madagascar: H. tricolor, H. carbonei, and H. luteostriatus. Similar to other species of this genus, the tadpoles of these species have a depressed, ovoid body-form and a generalized oral disc. The labial tooth row formula is 1/3(1). Examined phenotypes differed marginally between species. Compared to H. tricolor and H. carbonei, H. luteostriatus showed fewer cusps on the fork-like labial teeth, a lower ventral fin, and a shorter tail. The high morphological resemblance implicates an ecological similarity between species. Highly overlapping niches raise questions on how species co-occur.

Tadpoles of Three Species of the Rhinella granulosa Group with a Reinterpretation of Larval Characters

The Rhinella granulosa group currently comprises 14 species of Neotropical toads, and its monophyly is strongly supported by several synapomorphies, including a distinctive set of larval characters. Recently, the identities of specimens used in the description of the tadpoles of R. major and R. mirandaribeiroi were questioned. In this work, we revise the larval external morphology of these species based on properly identified tadpoles and examine for the first time the tadpoles of R. bernardoi. Tadpoles of R. major have the labial tooth row formula 2/2 and a striped tail pattern, which were recovered as synapomorphies of the group. In contrast, tadpoles of R. mirandaribeiroi show a third posterior labial ridge arranged on a medial flap, a condition suggested as a synapomorphy of a derived subclade of the R. granulosa group. Lastly, tadpoles of R. bernardoi differ from the remaining tadpoles within the group by lacking the typical striped tail muscle pigmentation.

A new species of Sarcohyla (Anura: Hylidae: Hylini) from the Sierra Madre del Sur of Guerrero and Estado de México, México.

We describe a new species of frog Sarcohyla floresi sp. nov. from the Sierra Madre del Sur of Guerrero and the southern part of Estado de México, based on specimens previously referred to as S. pentheter and newly obtained specimens. The new species has stream-dwelling tadpoles with labial tooth row formula 2(2)/3 and adults with a distinctive dark dorsolateral band bordered by a white line. S. floresi can be included in the S. bistincta group.

Morphological characteristics of tadpole and bioacoustic of species Black-spined toad Duttaphrynus melanostictus (Schneider, 1799) in Vinh City, Nghe An Province

This article showed the results of research on morphological characteristic and metamorphosis of a larval tadpole to juveniles and bioacoustic of adult male individuals of Black-spined toad Duttaphrynus melanostictus (Schneider, 1799) in Nghe An Province. During the reproductive period, the activity of calling a partner happens before it rains from 1 to 3 days, pairing when it rains. The body of tadpoles of Black-spined toad is black, small size, the labial tooth row formula is I(1+1)/III. The time of metamorphosis from stage 34 to stage 46 take from 13 to 16 days, at average temperature of 28.30C. In the reproduction season, adult male make the sound with duration 8.118 ± 3.985 (s), including 68.60 ± 28.08 pulses, the dominant frequency of pulses of 1522.262 ± 59.674 (Hz), the max power of pulses from 92.90 ± 105.10 (dB).

Smooth, striated, or rough: how substrate textures affect the feeding performance of tadpoles with different oral morphologies

For grazing animals that share spatial and alimentary resources, the relationship between differences in oral morphology and the physical properties of substrates can help explain how and where species forage. The substrates may require different efforts from animals to access and remove food from their surfaces. Variation in oral morphology may produce differences in animals’ feeding efficiency. We tested whether one substrate characteristic, the surface texture (i.e., smooth, striated and rough), influences the growth and food consumption rates of anuran larvae from nine species with different oral morphologies. Tadpoles with few keratinized oral structures and those with more gaps in the marginal papillae row were more efficient grazing on smooth and rough surfaces, respectively. This may indicate possible feeding specializations. Conversely, tadpoles with a high number of labial tooth rows, regardless of the number of gaps in these structures, and those with only a dorsal gap in the marginal papillae row were equally efficient feeding upon all substrate textures. Tadpoles with the generalized labial tooth row formula 2(2)/3(1), had higher growth rates than the other species, suggesting an adaptive significance for this common oral morphology. We demonstrated that species differ in feeding efficiency when grazing on substrates with different textures. This can help elucidate the adaptive significance of variation in tadpole oral morphology. We also provide insights on resource selection and niche partitioning among species, especially for those whose diets do not differ in quantity or quality, as it is common in anuran larval assemblages.

Field and laboratory observations on reproductive aspects of Pseudopaludicola ameghini (Cope, 1887) (Leptodactylidae: Leiuperinae)

ABSTRACT The genus Pseudopaludicola includes small-sized anurans, widely distributed throughout South America. Twenty-three out of the 25 species occur in Brazil. Although described more than a century ago, from mid-southern Mato Grosso state, central Brazil, Pseudopaludicola ameghini is poorly known. Here we describe the characteristics of reproductive site, amplexus, egg-laying behaviour, eggs and tadpoles of P. ameghini based on specimens and observations performed in the vicinities of the type locality. Pairs of P. ameghini reproduce in shallow and slow groundwater established on hydromorphic terrains, in open environments amidst the Brazilian Cerrado savanna. Reproductive activity occurred between 17:00 and 21:00 h at two sites studied from December 2013 to April 2014. Amplexus is axillary. Eggs are spherical, with a mean diameter of 5.1 mm (yolk plus jelly envelope). Oviposition occurs in shallow sites at a depth of nearly 2.0 cm. Females deposit their eggs one at a time, directly onto sediment at the bottom of waterbodies or attached to submerged vegetation. The tadpole body is oval in dorsal view and globular/depressed in lateral view; eyes are large and dorsally positioned. Nares are large, round, with a small apophysis on marginal rim, dorsally positioned, near the eyes. The spiracle is short, with posterodorsal opening. The oral disc is anteroventral, emarginated laterally, with one dorsal and two ventral gaps; the tooth row formula is 2(2)/2(1), and the upper jaw sheath is ‘arc’ shaped. Pseudopaludicola ameghini has a unique behaviour of oviposition among members of the genus. The differences in reproductive pattern and larval characteristics of P. mystacalis and P. ameghini reinforce the taxonomic validity of the latter, questioned until recently.

External Morphology and Internal Oral Features of the Tadpole of Crossodactylus caramaschii (Anura: Hylodidae)

We describe the larval external morphology and internal oral features of Crossodactylus caramaschii sampled in protected areas of the Atlantic Forest in southeastern Brazil. The tadpoles of C. caramaschii (Gosner stage 38) have an ovoid body in dorsal view and globular in lateral view, dorsal eyes, a ventral oral disc bordered by a single row of marginal papillae, with a wide gap on the anterior labium, and few and scattered submarginal papillae. The labial tooth row formula is 2(2)/3(1), with A-1 shorter than A-2, and P-3 shorter than P-1 and P-2. This is the first description of the larval morphology of this species and may help future studies on the intrageneric relationships of Crossodactylus.

The Tadpole of Scinax cardosoi (Carvalho-e-Silva and Peixoto, 1991), with Description of Internal Oral Morphology and Taxonomic Considerations (Anura: Hylidae)

Larval traits provide useful taxonomic characters. The only morphological synapomorphy that separates Scinax species from Ololygon species comes from larvae. However, tadpoles of Ololygon and Scinax remain undescribed; furthermore, there is a lack of information regarding their internal oral cavities. Herein, we describe the tadpole of Scinax cardosoi and its internal oral morphology. Overall, the body is triangular and depressed in lateral view and oval in dorsal view, the dorsal fin is slightly higher than the lower fin, and the tooth row formula is 2(1,2)/3. The tadpole of S. cardosoi can be distinguished from tadpoles of Ololygon and Scinax by its oral disc morphology and oral papillae arrangement. The position of the larval vent tube, as well as some adult features, suggest a close relationship between S. cardosoi and species of Ololygon, leading us to transfer the species from Scinax to Ololygon.

Tadpole of Pithecopus rusticus (Bruschi, Lucas, Garcia & Recco-Pimentel, 2014) (Anura, Phyllomedusidae): description of external morphology and natural history notes of a microendemic species

Abstract: Pithecopus rusticus is a newly described species, of which information on its natural history, vocalization and tadpole morphology are still lacking. Here, we describe the larval external morphology of P. rusticus from the type locality, in the municipality of Água Doce, state of Santa Catarina, southern Brazil, comparing it with that of other species of the genus Pithecopus and providing information on its natural history. Eggs from two spawns were collected and kept in the laboratory until hatching. The tadpoles of P. rusticus belong to the suspension-rasper guild. At Gosner stage 37, the tadpoles showed: body shape oval in dorsal view and triangular in lateral view; a tooth row formula of 2(2)/3(1); the third lower row six times shorter than others; marginal papillae uniserial, interrupted by a wide dorsal gap and with rounded tips; and a single row of alternate marginal papillae on lower lip. External morphological features were compared with those of other tadpoles of Pithecopus. Observations on the natural history of P. rusticus are also reported.

Tooth row variation in tadpoles of Dendropsophus labialis (Anura: Hylidae: Dendropsophini) and the evolution of oral morphology in the genus

Labial tooth row variation was assessed in Dendropsophus labialis tadpoles from the Cordillera Oriental in Colombia. The presence of a second anterior labial tooth row was detected, showing thus a labial tooth row formula of 2/2. This second anterior tooth row was present in a substantial number of individuals, suggesting that the observed variation is not unusual. This variation contradicts earlier reports about the number of labial tooth rows in this species, whose labial tooth row formula has been reported as 1/2 without variation. A novel ontogenetic pattern of tooth row addition was detected, differing from earlier observations made on Pseudacris regilla tadpoles in terms of tooth row appearance order. The taxonomic implications for these data are discussed along with the evolution of oral morphologies in the genus.

Description of the Tadpole ofPseudopaludicola cangaGiaretta and Kokubum, 2003 (Anura: Leptodactylidae)

We describe the external morphology, internal oral anatomy, and chondrocranium of Pseudopaludicola canga. The tadpole is diagnosed by the following combined characters: elliptic body, reniform nostril, dorsal fin starting at the body-tail junction and labial tooth row formula 2(2)/2(1) presenting two lateral gaps in the marginal papillae of the lower lip. Regarding the oral cavity, there is a pattern similarity in some characters among the three species of the genus for which the structure has been described; however, P. canga can be characterized by having a pair of infralabial papillae, irregular median ridge, three lingual papillae, fewer papillae in the buccal roof arena, and greater number of papillae in the buccal floor. The chondrocranium of P. canga differs from that of P. boliviana by presenting a distal connection between the pars alaris and pars corporis of the cartilago suprarostralis; and differs from P. falcipes by lacking a processus pseudopterygoideus. Further, our data emphasize the utility of larval characters as additional tools in the diagnosis of species within this genus.

Description of the Tadpole of Phyllomedusa azurea from the Brazilian Cerrado, with a Description of the Internal Oral Morphology of Phyllomedusa oreades

Abstract We present a description of the external morphology of Phyllomedusa azurea and describe the internal oral morphology of P. azurea and P. oreades from populations of the Brazilian Cerrado. We also present a comparison with the available descriptions of the external morphology of tadpoles from the P. hypochondrialis group and review the internal oral morphology of the Phyllomedusa genus. The tadpole of P. azurea is characterized by a tooth row formula of 2(2)/3(1), few submarginal papillae, and spiracle positioned ventrally. Phyllomedusa oreades has a diamond-shaped buccal floor, numerous pustulations randomly distributed throughout the buccal floor arena, and a triangular buccal roof. The variation observed in the morphology of P. azurea tadpoles highlights the need to understand how morphological variation affects traits used in species diagnosis and the extent to which this variation could be explained by resource use, geographic variation, and/or ontogeny.

The tadpole of Scinax skuki (Anura: Hylidae) from the type locality, with a description of its larval skeleton

ABSTRACTHerein, we provide external and internal morphological data of Scinax skuki tadpoles from its type locality. The benthic tadpole of S. skuki has eyes and nostrils positioned dorsally, vent tube dextral and reaching the free margin of the ventral fin, oral disk ventral with posterior margin concave when partially closed, labial tooth row formula 2/3, and the presence of nonpigmented spurs behind the lower jaw. These characters, together with the absence of a tectum parietale, and the shapes of the pars articularis quadrati and suprarostral, are useful for species identification and may be informative for systematic purposes.

The Tadpole ofProceratophrys dibernardoi(Brandão, Caramaschi, Vaz-Silva, and Campos, 2013) (Anura, Odontophrynidae)

Abstract Proceratophrys dibernardoi is a newly described species belonging to the Proceratophrys cristiceps group. Herein, we describe the external morphology of tadpoles of P. dibernardoi. Although external larval morphology of P. cristiceps group members is quite similar, the tadpole of P. dibernardoi may be distinguished by a combination of morphological traits, such as body shape that is elliptical in dorsal view and depressed in lateral view; a snout that is rounded in dorsal and lateral views; small, reniform nares with a small marginal rim; and a spiracle with its centripetal wall completely fused to the body wall. The oral disc is ventrally located, with lateroventral emarginations; its tooth row formula is 2(2)/3(1).