The Nguru Mountains in the central Eastern Arc Mountains (EAM) consist of three main protected areas (Mkingu, Kanga and Magotwe), which form an important hotspot for endemic species of vertebrates and plants in Tanzania. However, the herpetofauna of the Nguru are relatively poorly understood, and rapid deforestation highlights the urgent need for comprehensive biodiversity studies. Using standardized survey methods, we conducted amphibian surveys in Nguru Mountains between May 2022 and November 2024, and together with literature and databases search, we provide an annotated amphibian checklist. Using molecular barcoding, we identify 42 lineages of amphibians in the Nguru Mountains, 15 of which are candidates for species new to science. Twenty-eight lineages are endemic to the Eastern Arc Mountains of Tanzania, eight of them being restricted to Nguru. Treating these new records as species would rank the Nguru Mountains third out of the 12 Eastern Arc Mountain blocks for the number of endemic amphibians, after Udzungwa and Uluguru. However, the identified lineages await formal description, and the partial sampling and taxonomic issues detected here, are common to all Eastern Arc Mountains. This study therefore highlights the reality of the Linnean shortfall even in recognized biodiversity hotspots, and how taxonomic work is required to remedy this. The impact of deforestation on Nguru amphibians is yet to be quantified, however this study helps to form a baseline for future studies.
Amphibians of the Afrobatrachia clade represent a major component of sub-Saharan Africa's biodiversity, yet they remain underrepresented in genomic databases. Here, we present the first whole-genome assembly of the Common Reed Frog, Hyperolius viridiflavus viridiflavus Ahl, 1931 from Ethiopia, a member of the H. viridiflavus superspecies complex. The genome was sequenced using PacBio HiFi long-read technology and assembled de novo with HiFiasm, resulting in a 4.4 Gb assembly across 10,009 contigs with an N50 of 1.09 Mb. Genome completeness had a BUSCO score of 84.2%, with 29,809 annotated genes, including 27,983 protein-coding genes and 942 long non-coding RNAs. Despite a similar estimated size, scaffolding against the chromosome-level genome of Hyperolius riggenbachi Nieden, 1910 revealed low mapping coverage (0.0654 per base across 1 Mb windows), likely due to phylogenetic divergence (∼14 Mya) and high repeat content. The complete mitochondrial genome (23,453 bp) was also assembled and annotated, revealing structural differences from closely related species. Phylogenomic analyses using 416 single-copy BUSCO genes and mitochondrial 16S sequences confirmed the distinctiveness of H. v. viridiflavus within the Hyperoliidae. As only one other Afrobatrachian genome exceeds 50% completeness in public databases (H. riggenbachi), this genome expands the resources available for African frogs and supports future research in systematics and conservation. Further, when considering the complex taxonomy and evolutionary history of the H. viridiflavus superspecies complex, this genome can serve as a tool for species delimitation and conservation when compared to other species and subspecies within the clade.
For the last century, herpetologists have referred to any Nectophrynoides Noble, 1926 toad characterized by a large, robust body, with large, distinct parotoid glands, as Nectophrynoides viviparus (Tornier, 1905). Consequently, Nectophrynoides viviparus is also considered to have the broadest distribution of all its congeners, with populations ranging from the Tanzanian Southern Highlands, close to the Tanzania-Malawi border, through the Udzungwa and Mahenge Mountains in the south to Uluguru, Rubeho, and Nguru Mountains in the central part of the Eastern Arc Mountains. However, there is underappreciated morphological diversity within what is generally referred to as N. viviparus, and various populations are isolated by large distances and geographical barriers. Recent molecular studies have shown that N. viviparus from the Southern Highlands, the type locality, is genetically distinct from all other N. viviparus populations in the Eastern Arc Mountains, suggesting the existence of a species complex warranting taxonomic revision. Here, we present an integrative taxonomic assessment of southern populations by supplementing the genetic results with the analysis of morphometric and morphological data for 257 specimens assigned to N. viviparus, including museomic data for name-bearing types. Based on the results, we describe three new species from the N. viviparus species complex, covering the southern EasternArc Mountains populations. Together with a revised morphological key to the genus and a gazetteer of known populations, we provide Extent of Occurrence and Area of Occupancy for N. viviparus sensu stricto and the new species to investigate their conservation status compared to other members of the genus.
Nectophrynoides saliensis sp. nov. Suggested English common name. Mahenge glandular tree toad. Suggested Kiswahili common name. Chura manundu wa Mahenge. Taxonomic remarks. This species has previously been referred to as “ Nectophrynoides sp 13 ” by Liedtke et al. (2016). Holotype. An adult presumably female specimen in the Museo Tridentino di Scienze Naturali, Trento, Italy, MUSE 13758 (KMH 26644) collected December 2005 in Sali F. R., Mahenge Mountains, Morogoro Region, Tanzania (approximate coordinates: – 8.93, 36.65) at 1050–1500 m a. s. l. by Frontier-Tanzania (Menegon et al. 2011 a) (Fig. 7 D). Paratypes. Series of adults and subadults: MUSE 13754 (KMH 26637), 13755 (KMH 26638), 13756 (KMH 26639), 13757 (KMH 26641) and 13759 (KMH 26998), all with the same collection data as the holotype. Definition. A member of the Nectophrynoides viviparus species complex based on overall body proportions, glandular limbs and large parotoid glands (Fig. 7 D), as well as genetic affinities based on mitochondrial markers (Fig. 1). This species is characterised by the unique combination of the following set of characters: (1) indistinct glandular masses on limbs; (2) medium body size (adult SUL 20.8–34.3 mm, mean 26.30 ± 5.02 mm); (3) weakly expanded rounded finger and toe tips with minute discs; (4) parotoid gland spearhead shaped; (5) relative head width (HW / SUL) 0.40–0.43; and (6) relative head length (HL / SUL) 0.37–0.40. Diagnosis. Nectophrynoides saliensis sp. nov. is easily distinguished from N. asperginis, N. cryptus, N. frontierei, N. laevis, N. pseudotornieri, N. wendyae by having a distinct tympanum. The smooth dorsal surface of Nectophrynoides saliensis sp. nov. is covered with glandular patches and warts, indistinct glandular masses on limbs, and the parotoid glands form a large distinct spearhead shape, which distinguishes it from N. laticeps, N. minutus, N. tornieri, N. paulae, N. poyntoni, N. vestergaardi. Nectophrynoides saliensis sp. nov. is distinguishable from N. viviparus sensu stricto by having indistinct limb glands. The finger- and toe-tip expansion of N. saliensis sp. nov. are also more expanded than N. viviparus sensu stricto, which has more slender and rounded fingers. The parotoid glands are elongated, and spearhead shaped, narrowing to a thin acuminate shape posteriorly (Fig. 9 D), whereas the parotoid of N. viviparus sensu stricto are fusiform shaped and rounded posteriorly (Fig. 9 A). Nectophrynoides saliensis sp. nov. is distinguished from Nectophrynoides luhomeroensis by lacking distinct limb glands (vs distinct), differently shaped parotoid glands (spearhead vs rhomboid [Fig. 9 D and Fig. 9 B, respectively]), larger relative head size (HL / SUL 0.37–0.40 vs 0.33–0.37, and HW / SUL 0.40–0.43 vs 0.35–0.39), and from N. uhehe by a much smaller maximum body size (SUL 34.3 mm vs 52.5 mm), by lacking distinct limb glands (vs distinct), and differently shaped parotoid glands (spearhead vs kidney [Fig. 9 D and Fig. 9 C, respectively]). Generalised description. A medium-sized (SUL: 34.3 mm) and robust Nectophrynoides with relatively short, muscular and slightly glandular limbs. The snout shape is triangular with a rounded tip and extending slightly beyond the upper lip. The canthus rostralis is angular. The tympanum is distinct. The parotoid glands are distinct and continuous with the dorsal orbits. The parotoid glands extend from the posterior end of the eyes to above the arm insertion in the scapular region forming a rough spearhead shape (Fig. 9 D). The body has small irregular glandular bumps and patches scattered across the dorsal and lateral surfaces. The limbs with indistinct glandular masses. The length of the foot is greater than the length of the tibia. The hands and feet with rudimentary webbing. The finger and toe-tips are expanded and rounded. In preserved specimens, the colouration and patterning are variable. The ground colour is very dark tawny brown with ash grey glandular bumps. The glandular masses on limbs and the parotoid glands are ash grey with dark tawny brown patterning. Description of holotype. MUSE 13758 (KMH 26644), presumably female adult. The specimen has a mid-ventral incision along the body. All measurements are given in mm. A medium-sized and robust specimen (SUL: 34.3, SVL: 35.0). Width of head (HW: 13.6) almost equal to length of head (HL: 13.1). Lower jaw rounded in dorsal and ventral profile with slightly flattened and blunted snout. Wide triangular snout slightly rounded anteriorly. In lateral profile, anterior end of snout is level with bottom of eye. Nostrils situated on either side of snout, at level of eye centre (ND: 2.3), and clearly visible dorsally. Eyes relatively large and bulging in dorsal profile (ED: 3.6). Distance between eye and naris (END: 3.0) greater than distance between naris and tip of snout (NSD: 1.5). In lateral profile, eye and dorsal orbit continuous with anterior end of snout to scapular region. Canthus rostralis angular and loreal region concave from top of canthus rostralis to edge of upper jaw. Canthus rostralis visible in dorsal profile. Tympanum and tympanic annulus distinct and rounded. Horizontal diameter of tympanum (TYMP: 1.4) less than half of horizontal diameter of eye. Forelimbs muscular and relatively short. Forearm longer than humerus (FOL: 9.3, HUL: 6.8), hand longest (HAL: 11.4). Outer metacarpal tubercle length equal to width (OMCL: 2.0, OMCW: 2.0), length of inner metacarpal tubercle shortest (IMCL: 1.5). First fingertip less expanded (F 1 W: 0.9) than third fingertip (F 3 W: 1.0). Hindlimbs muscular and relatively long. Tibia longer than thigh and metatarsus (TIL: 17.8, THL: 17.0, ML: 10.3), foot longest (FL: 18.9). Outer metatarsal tubercle length (OMTL: 1.7) shorter than inner metatarsal tubercle (IMTL: 2.6). First and fourth toe tip equally expanded (T 1 W: 1.0, T 4 W: 1.0). Hindlimbs more than twice as long as forelimbs (HIL: 64.1, FORL: 27.5). Skin texture smooth on glandular and non-glandular surfaces. Dorsal head glandular with small pores. Dorsal orbits glandular with medium pores. Dorsum with small, irregular, raised glandular bumps. Front and hind limbs with indistinct glandular masses. Humerus and femur have small irregular glandular bumps. Forearm, hands, tibia, metatarsus and feet have indistinct glandular masses with large pores. Parotoid glands paired and continuous with dorsal orbits. Parotoid glands with medium pores. Parotoid glands situated from posterior to eye to scapular region above arm insertion. Parotoid glands rough spearhead shaped, widest posterior to eye above angle of jaw and tympanum, narrowing to an acuminate shape in scapular region above arm insertion. Parotoid glands extend to lateral surfaces of tympanic region posterior to tympanum and become irregular patches of glandular and non-glandular skin. Lateral head consists of irregular patches of glandular and non-glandular skin. Posterior and inferior surface of tympanum to posterior end of eye has 10–15 small to medium glandular masses each with a small translucent spine. Flank with small, irregular, raised glandular bumps. Ventral surfaces non-glandular except for femoral area with small, raised bumps. Fingers and toes slender with slightly expanded and rounded digit tips. Hands and feet with distinct, raised tubercles and rudimentary webbing. Feet slightly more webbed extending slightly beyond the first subarticular tubercles. Dorsal ground colour very dark tawny brown. Dorsum and flank with many ash grey, raised, glandular bumps. Dorsal head with a large ash grey glandular patch with very dark tawny brown spots. Limbs, hands and feet with ash grey glandular patches, spots and stripes. Tympanic region tawny brown with ash grey glandular patches. Lateral head ash grey. Canthus rostralis and nostrils tawny brown. Dorsal orbits bluish ash grey. Ventral surface of limbs, abdomen and chin cream. Pectoral regions cream with caramel brown patches. Ventral surfaces of hands and feet caramel brown with cream tubercles, fingers and toes. Femoral area caramel brown with cream bumps. No photographs or field notes describing colouration of holotype in life are currently known. Variation in the species. MUSE 13755 tawny brown dorsal ground colour with very dark tawny brown patterning on dorsal and ventral surfaces. MUSE 13755 has a less distinct tympanum. MUSE 13755 and 13759 have very slightly pointed snout tips. Sexual dimorphism was not observed in preserved material, but females are expected to be larger than males, like congeners. Preservation status. The holotype and paratypes are in fair condition but show evidence of previous exposure to unsuitable preservation. The specimens are shrunken, stiff, and partially desiccated, with dried finger- and toe tips. Genetics. Holotype MUSE 13758 and paratypes MUSE 13754, 13755, 13757 and 13759 have been successfully sampled and sequenced (Liedtke et al. 2016). Nectophrynoides saliensis sp. nov. is genetically distinct according to Liedtke et al. (2016), who used species delimiting approaches (specifically bGYMC) to examine current bufonid diversity against undescribed diversity. In their analysis, N. saliensis sp. nov. was genetically distinct and identified as “ Nectophrynoides sp 13 ”. MUSE 13758 is 3.11 % genetically different in partial (ca. 550 bp) 16 S rRNA from all other Nectophrynoides, with the closest relative being Nectophrynoides viviparus sensu stricto (see Table 3). This is rather at the inter-specific level than the infra-specific (population) level; the intra-specific distance between sequenced specimens is 0–0.718 %. Advertisement call. Not recorded. Etymology. The species Nectophrynoides saliensis sp. nov. is named after the location where the species was discovered, which is Sali F. R. in Mahenge Mountains, Tanzania. The suggested common name is a reference to the distribution of this species in the Mahenge Mountains, its glandular skin, and semi-arboreal lifestyle. Habitat and
Taxonomy is a highly dynamic science upon which most biodiversity studies rely. Constant revisions of species delimitation hypotheses, using ever-growing amounts of data and tools cause species numbers and identities to continuously and rapidly change. Reptiles are the most species rich terrestrial vertebrate group and are amongst the most threatened and least known vertebrate taxa, representing nearly half of all datadeficient terrestrial vertebrate species. Every year hundreds of new species are described and dozens are revised, resulting in synonymizations, splittings, generic reassignments, or elevation from synonymy or from subspecies into species status. The nomenclature of this group is therefore highly dynamic and consequently, to integrate available reptile datasets generally requires extensive nomenclature review, especially for broad scale analyses. letsRept is a new R package that integrates the Reptile Database - the best curated and reliable global taxonomic reference for reptiles - into the R programming environment. Its main functions allow users to retrieve the most up-to-date taxonomic information in real time, to compare lists of species names to current nomenclature, and to detect names that have been changed by either lumping or splitting, all through web scraping techniques. Additional functions allow to produce quick taxonomic summaries, access species accounts, retrieve full reference lists and more. By permitting to embed the Reptile Database directly into R workflows, the letsRept package improves the integration of datasets from different sources, with authoritative taxonomy, reducing data loss due to nomenclature mismatch and improving the consistency in biodiversity analyses.
Effective conservation measures require accurate and complete species inventories, which are however often missing for particularly biodiverse regions of concern. The montane forests of the Eastern Arc Mountains (EAM) in East Africa represent fragmented relics of unique habitats that harbour remarkable levels of plant and animal diversity, including many endemic and threatened species most of which are poorly known. The present study focuses on the Ukaguru Mountains, an important mountain block in the central EAM, and expands on a recent study that summarized data from 30 years of amphibian surveys. Using systematic sampling (2022-2024) in localities that are less heavily impacted by anthropogenic activities than previously surveyed sites, we increase the number of documented amphibian species from 17 to 19, adding Xenopus cf. victorianus and a newly described species (see below). Among the three Ukaguru-endemic toads which have not been recorded since more than two decades, we re-discovered Nectophrynoides laticeps and N. paulae but failed to record the enigmatic Churamiti maridadi, which according to a dedicated extinction model has an updated probability of only 47.6% of still being extant. Based on genetic, morphological and bioacoustic evidence, we also describe a new large-bodied species of Arthroleptis (Arthroleptis mamiwakisaraensis sp. nov.), shedding further light into the evolution of 'giant' congeners which inhabit other mountain blocks in the EAM. Given the rapid deforestation of the EAM for which the Ukagurus are no exception, our findings give rise to concerns regarding current and future extinction risks within unique mountain amphibian assemblages, also affecting species which potentially still await description. http://zoobank.org/urn:lsid:zoobank.org:pub:04EC6DEE-D2D9-463D-B8AB-18560AC2AB85
Nectophrynoides luhomeroensis sp. nov. Suggested English common name. Luhomero glandular tree toad. Suggested Kiswahili common name. Chura manundu wa mlima Luhomero. Taxonomic remarks. This species has previously been referred to as “ Nectophrynoides sp 06 ” by Liedtke et al. (2016). Holotype. An adult female specimen in the Natural History Museum, London, United Kingdom, BM 1983.6 (KMH 2438) collected on the 25 th of October 1987 in Luhomero Mountains, Udzungwa Mountains National Park, Udzungwa Mountains, Iringa Region, Tanzania (approximate coordinates: – 7.78, 36.60) at 2500 m a. s. l. by Jan Kielland (Fig. 7 B). Paratypes. Series of seven subadult and one juvenile specimens in the Museo Tridentino di Scienze Naturali, Trento, Italy, MTSN 8311, 8312, 8397, 8401, 8404, 8405, 8408 and 8409, collected on the 15 th of September 2004 in Luhomero Mountains, Udzungwa Mountains National Park, Udzungwa Mountains, Iringa Region, Tanzania (–7.6965, 36.5722) at 2200 m a. s. l. by Michele Menegon. Definition. A member of the Nectophrynoides viviparus species complex based on overall body proportions, glandular limbs and large parotoid glands (Fig. 8), as well as genetic affinities based on mitochondrial markers (Fig. 1). This species is characterised by the unique combination of the following set of characters: (1) distinct glandular masses on limbs; (2) medium body size (adult SUL 18.4–30.0 mm, mean 21.79 ± 3.77 mm); (3) expanded, rounded finger and toe tips with small discs; (4) parotoid gland rhomboid and slightly pointed posteriorly; (5) relative head width (HW / SUL) 0.35–0.39; and (6) relative head length (HL / SUL) 0.33–0.37. Diagnosis. Nectophrynoides luhomeroensis sp. nov. is easily distinguished from N. asperginis, N. cryptus, N. frontierei, N. laevis, N. laticeps, N. minutus, N. paulae, N. poyntoni, N. pseudotornieri, N. tornieri, N. vestergaardi and N. wendyae by having distinct glandular masses on limbs (versus indistinct or absent). Nectophrynoides luhomeroensis sp. nov. is distinguishable from N. viviparus sensu stricto by its slightly smaller body size (SUL 18.4–30.0 mm vs 18.8–37.2 mm), finger- and toe-tips more expanded and less slender and rounded, and parotoid glands rhomboid shaped, slightly pointed posteriorly (Fig. 9 B) (vs fusiform shaped and rounded posteriorly [Fig. 9 A]). For comparison to the other two new species described herein, refer to the diagnoses of the respective taxa, below. Generalised description. A medium-sized (SUL: 30 mm) and robust Nectophrynoides with relatively short, muscular, and glandular limbs. The snout is triangular with a rounded tip and extends slightly beyond the upper lip. The canthus rostralis is slightly concave and flattened. The tympanum is distinct. The parotoid glands are distinct and continuous with the dorsal orbits. The parotoid glands extend from the posterior end of the eyes to above the arm insertion in the scapular region forming a rhomboid shape (Fig. 9 B). The body has irregular glandular patches scattered across the dorsal and lateral surfaces. The limbs with distinct glandular masses. The length of the foot is greater than the length of the tibia. The hands and feet with rudimentary webbing. The finger and toe-tips are expanded and rounded. In preserved and alive specimens, the colouration and patterning are highly variable (Fig. 8). Preserved specimens have a cream to dark tawny brown ground colour with darker lateral flanks. The glandular masses are lighter tawny brown with caramel brown patterning or cream brown with little to no patterning. Description of holotype. BM 1983.6 (KMH 2438), an adult female. There are large yolky eggs visible through the abdomen. All measurements are given in mm. A medium-sized and robust specimen (SUL: 30.0, SVL: 30.7). Width of head (HW: 10.7) almost equal to length of head (HL: 10.9). Lower jaw rounded in dorsal and ventral profile with a very slightly blunted snout. Triangular snout slightly rounded anteriorly. In lateral profile, anterior end of snout level with bottom of eye, and inclines to upper jaw. Nostrils situated on either side of snout, at level of eye centre (ND: 2.7), and clearly visible dorsally. Eyes relatively large and bulging in dorsal profile (ED: 3.4). Distance between eye and naris (END: 2.1) greater than distance between naris and tip of snout (NSD: 1.8). In lateral profile, eye and dorsal orbit are continuous with anterior end of snout to scapular region. Canthus rostralis flattened and loreal region slightly concave from top of canthus rostralis to edge of upper jaw. Canthus rostralis visible in dorsal profile. Tympanum and tympanic annulus distinct and rounded. Horizontal diameter of tympanum (TYMP: 1.1) roughly 1 / 3 of horizontal diameter of eye. Forelimbs muscular and relatively short. Forearm longer than humerus (FOL: 8.0, HUL: 5.9), hand longest (HAL: 9.4). Outer metacarpal tubercle length greater than width (OMCL: 1.9, OMCW: 1.5), inner metacarpal tubercle shortest (IMCL: 1.0). First and third fingertip almost equally expanded (F 1 W: 0.9, F 3 W: 0.9). Hindlimbs muscular and relatively long. Tibia and thigh almost equal in length (TIL: 12.3, THL: 12.7), roughly 1 / 3 longer than metatarsus (ML: 8.0), foot longest (FL: 14.0). Outer metatarsal tubercle length (OMTL: 1.4) shorter than inner metatarsal tubercle (IMTL: 2.1). First toe tip less expanded (T 1 W: 0.8) than fourth toe tip (T 4 W: 0.9). Hindlimbs more than twice as long as forelimbs (HIL: 47.0, FORL: 23.3). Skin texture smooth on glandular and non-glandular surfaces. Dorsal head and dorsum to cloacal region glandular with small pores. Dorsal orbit glandular with medium pores. Dorsum with irregular, large circular glandular masses. Dorsal surface of limbs with glandular masses. Humerus and femur with irregular glandular masses. Forearm, hands, tibia, metatarsus and feet have slightly swollen glandular masses with large pores. Parotoid glands paired and continuous with dorsal orbit. Parotoid glands with large pores and spongy texture. Parotoid glands situated from posterior to eye to scapular region above arm insertion. Parotoid glands rhomboid shaped, widest posterior to eye above angle of jaw and narrows to a slightly pointed shape in scapular region above arm insertion. Parotoid glands extend to lateral surface of tympanic region posterior to tympanum and narrows before arm insertion. Lateral surface of head consists of irregular patches of glandular and non-glandular skin. Posterior and inferior surface of tympanum to posterior end of eye with 10–15 small to medium glandular masses each with a small translucent spine. Flank with glandular patches. Ventral surfaces non-glandular except for femoral area with small, raised bumps. Fingers and toes slender with slightly expanded and rounded digit tips. Hands and feet with distinct tubercles that are raised from the skin. Hands and feet with rudimentary webbing. Feet slightly more webbed extending slightly beyond the first subarticular tubercles. Dorsal ground colour tawny brown. Head and dorsum with caramel brown patches and spots. Dorsum and femur with tawny brown circular raised glandular bumps without patterning. Parotoid glands, limbs, glandular masses on limbs, hands, and feet tawny brown with caramel brown patches and spots. Femur dark tawny brown close to body and caramel towards knee. Flank ground colour caramel brown with few tawny brown spots toward dorsal margin and cream brown patterning toward ventral margin. Lateral head tawny brown with cream and caramel brown patches. Nostrils caramel brown. Abdomen, pectoral region and chin cream with tawny brown patches and spots. Ventral surface of hands and feet tawny brown with cream tubercles, fingers and toes. Ventral surface of limbs dark tawny brown. Femoral area caramel brown with tawny brown bumps. No photographs or field notes describing colouration of holotype in life are currently known. Variation in the species. Paratypes are smaller in body size and currently considered subadults. MTSN 8311 with dark tawny brown ground colour covering dorsal and lateral surfaces with tawny brown glands. MTSN 8405 and 8409 with cream ground colour and less distinct tympana. MTSN 8312 and 8405 with several white glandular patches and spots on lateral and dorsal surfaces. Sexual dimorphism was not observed in preserved material; females are expected to be larger than males as seen in congeners, but adult male specimens are needed to confirm this. Photographs and field notes of paratypes, and other individuals, highlight a strong variation in colouration and patterning (Fig. 8). Preservation status. The holotype is in good condition. The paratypes are generally in fair condition but are soft-fixed, making them fragile and difficult to work with. The condition of paratype MTSN 8312 has deteriorated since measurements were taken; it was then in fair condition but is now poorer. Genetics. Paratypes MTSN 8404 and 8405 have been successfully sampled and sequenced (Liedtke et al. 2016). Nectophrynoides luhomeroensis sp. nov. is genetically distinct according to Liedtke et al. (2016), who used species delimiting approaches (specifically bGYMC) to examine current bufonid diversity against undescribed diversity. In their analysis, N. luhomeroensis sp. nov. was genetically distinct and identified as “ Nectophrynoides sp 06 ”. MTSN 8405 is at least 3.13 % genetically different in partial (ca. 550 bp) 16 S rRNA from all other Nectophrynoides, with the closest relative being N. uhehe sp. nov. (see Table 3). This is rather at the inter-specific level than the infra-specific (population) level; the intra-specific distance between sequenced specimens is 0–0.478 %. Advertisement call. Not recorded. Etymology. The species Nectophrynoides luhomeroensis sp. nov. is named after the type locality, which is Luhomero Mountains, within the Udzungwa Mountains National Park, Udzungwa Mountains, Iringa Region, Tanzania. The suggested common name is a reference
Nectophrynoides viviparus (Tornier, 1905) Suggested English common name. Southern Highlands glandular tree toad. Suggested Kiswahili common name. Chura manundu wa nyanda za juu kusini. Taxonomic remarks. In the following, we provide a re-description of Nectophrynoides viviparus sensu stricto as revealed by our museomics analysis to comprise the clade from the Southern Highlands; it supersedes previous redescriptions by e. g., Loader et al. (2009), which included non-conspecific members of the complex and cannot therefore be used to distinguish among members of that clade. However, we do not provide a redescription of the lectotype, which was adequately described by Loader et al. (2009). Lectotype. An adult female specimen in the Museum für Naturkunde, Berlin, Germany, ZMB 21775 collected 2 nd of June 1900 in Ngosi (Ngozi) Crater, Poroto Mountains, Mbeya Region, Tanzania (approximate coordinates: – 9.00, 33.56), also known as “ Kratersee des Nyisilvulkans ” on the original label, by Friedrich Fülleborn (Fig. 7 A). Paralectotypes. Large series of subadult and adult specimens in the Museum für Naturkunde, Berlin, Germany, ZMB 71524 and 71525 with the same collection data as the lectotype. ZMB 21784, 21788, 25296, 71527 and 71528 collected in “ Daressalaam ” by Dr. Emil Werth. ZMB 25297 collected in “ Amani ” by Prof. Dr. Julius Vosseler. ZMB 25261, 25268, 25312, 71529, 71530, 71535 and 71536 collected in “ Südliches Deutsch-Ostafrika ” (southern Tanzania), ZMB 71187 –95, 78704–9 and 78798–803 collected between 26 th and 27 th of October 1899 in “ Rugwe (D. O. A.) ” (Rungwe, Deutsch-Ostafrika), and ZMB 84908, 84909 and 84910 collected between 26 th and 27 th of October 1899 in “ Rugwe-Gebirge ”, Tanzania by Friedrich Fülleborn. Type specimen remarks. One specimen in the Natural History Museum, London, UK, BMNH 1947.2.1945 collected by Friedrich Fülleborn without collection data, is part of the original type series. One specimen in the American Museum of Natural History (AMNH), New York City, New York, USA, AMNH A 23562 collected in “ Daressalaam ”, Tanzania by Dr. Emil Werth, is part of the original type series of Nectophryne werthi (Nieden 1911; Loader et al. 2009). Nota bene. The paralectotypes ZMB 21784, 21788, 25296, 25297, 71527 and 71528 are also co-types of Nectophryne werthi (Nieden 1911; Loader et al. 2009) and are not conspecific with the rest of the type series of N. viviparus sensu stricto (Fig. 1). Revised definition. A member of the Nectophrynoides viviparus species complex based on overall body proportions, glandular limbs and large parotoid glands (Fig. 4), as well as genetic affinities based on mitochondrial markers (Fig. 1). This species is characterised by the unique combination of the following set of characters: (1) distinct glandular masses on limbs; (2) medium body size (adult SUL 18.8–37.2 mm, mean 24.76 ± 4.75 mm); (3) fingers slender with rounded discs; and (4) parotoid gland fusiform and widest above arm insertion. Revised diagnosis. Nectophrynoides viviparus sensu stricto is easily distinguished from N. asperginis, N. cryptus, N. frontierei, N. laevis, N. laticeps, N. minutus, N. paulae, N. poyntoni, N. pseudotornieri, N. tornieri, N. vestergaardi and N. wendyae by having distinct glandular masses on limbs (versus indistinct or absent). Preservation status. The lectotype is in fair condition, although showing signs of discolouration, softness and other ‘ old’ specimen attributes. The paralectotypes range from bad to good condition, the specimens in bad condition are dehydrated, and some have had incisions made on the thigh or inguinal region. Genetics. MTSN 9365 and 9383 have been successfully sampled and sequenced (Liedtke et al. 2016). Museomics were done on the following name-bearing types ZMB 21775, 21784, 21788, 25261, 25296, 25297, 25312, 71187 and 71193. Nectophrynoides viviparus sensu stricto is genetically distinct according to Liedtke et al. (2016), who used species delimitation approaches (specifically bGYMC) to examine current bufonid diversity against undescribed diversity. In their analysis, N. viviparus sensu stricto was genetically distinct and identified as “ Nectophrynoides viviparus ”. MTSN 9365 and 9383 are at least 3.11 % genetically different in partial (ca. 562 bp) 16 S rRNA from all other Nectophrynoides, with the closest relative being N. saliensis sp. nov. (see Table 3). This is rather at the inter-specific level than the infra-specific (population) level; the intra-specific distance between sequenced specimens is 0–0.561 %. Bioacoustics. The call analysis was carried out on a single audio file consisting of 7 calls with a mean of 13.43 pulses per call in each audio file. The call was recorded 26 th of January 2011 in Mdandu, Livingstone Mountains, the Southern Highlands, Tanzania (–9.7719, 34.7867) at around 2100 m above sea level (a. s. l.) by Michele Menegon near a stream in a closed canopy montane rainforest (Fig. 5). The calls are not associated with any known specimen. However, to our knowledge, this is the only audio file from the Southern Highlands populations, and we therefore cautiously assume that this audio file is a suitable representative of Nectophrynoides viviparus sensu stricto. Audio file containing calls of this species deposited online (https://doi.org/10.5281/zenodo.17277236). The calls consist of a sequence of 12–15 pulses per call (Fig. 6 A). The mean call duration is 0.23 ± 0.03s (range: 0.20– 0.27s), with a mean call interval of 16.00 ± 5.29s (7.36– 22.27s). Each call contains a mean of 13.43 ± 1.27 pulses (12–15), with a mean pulse duration of 0.017 ± 0.001s (0.005 – 0.019s). The mean dominant frequency is 1877.71 ± 54.62 Hz (1809–1979 Hz). The call structure is illustrated in a spectrogram and waveform in Fig. 6 A. The male advertisement call is monophasic consisting of pulse trains of similar proportions. The first pulse has the highest intensity followed by a series of pulses that slowly decrease in intensity (Fig. 6 A). The audio file used for this analysis was sound polluted by a nearby stream. For statistical comparisons between Nectophrynoides viviparus sensu stricto and N. uhehe sp. nov. see Table 2. For visual comparisons between N. viviparus sensu stricto and N. uhehe sp. nov. see Fig. 6. More behaviour studies and recordings need to be made in the field to rule out certain factors that could shape the call, such as areas of close vicinity with a high competition between males, stress calls, and simplified communicational calls. Etymology. The Latin adjective> viviparus, meaning ‘ bearing live offspring’. The suggested common name is a reference to the distribution of this species across the Southern Highlands, its glandular skin, and semi-arboreal lifestyle. One of the previous common names of this species was “ Morogoro tree toad ”, but this is no longer a valid representation of this species since it is not considered to occur in the Morogoro Region or District of eastern Tanzania. Habitat and life history. As mentioned in Loader et al. (2009), and with additional collection data from ZMUC specimens, collectors have found this species from approximately 1800 to 2800 m a. s. l. The species (here referring to N. viviparus sensu stricto) has been associated with a range of different habitats such as wet, open, closed, primary, secondary and disturbed forests, ericaceous heathland, montane grassland and bamboo forests. The original description, and observation of toadlets, suggest that this species is ovoviviparous, as in its congeners.
Amphibians represent a diverse group of tetrapods, marked by deep divergence times between their three systematic orders and families. Studying amphibian biology through the genomics lens increases our understanding of the features of this animal class and that of other terrestrial vertebrates. The need for amphibian genomic resources is more urgent than ever due to the increasing threats to this group. Amphibians are one of the most imperiled taxonomic groups, with approximately 41% of species threatened with extinction due to habitat loss, changes in land use patterns, disease, climate change, and their synergistic effects. Amphibian genomic resources have provided a better understanding of ontogenetic diversity, tissue regeneration, diverse life history and reproductive modes, antipredator strategies, and resilience and adaptive responses. They also serve as essential models for studying broad genomic traits, such as evolutionary genome expansions and contractions, as they exhibit the widest range of genome sizes among all animal taxa and possess multiple mechanisms of genetic sex determination. Despite these features, genome sequencing of amphibians has significantly lagged behind that of other vertebrates, primarily due to the challenges of assembling their large, repeat-rich genomes and the relative lack of societal support. The emergence of long-read sequencing technologies, combined with advanced molecular and computational techniques that improve scaffolding and reduce computational workloads, is now making it possible to address some of these challenges. To promote and accelerate the production and use of amphibian genomics research through international coordination and collaboration, we launched the Amphibian Genomics Consortium (AGC, https://mvs.unimelb.edu.au/amphibian-genomics-consortium) in early 2023. This burgeoning community already has more than 282 members from 41 countries. The AGC aims to leverage the diverse capabilities of its members to advance genomic resources for amphibians and bridge the implementation gap between biologists, bioinformaticians, and conservation practitioners. Here we evaluate the state of the field of amphibian genomics, highlight previous studies, present challenges to overcome, and call on the research and conservation communities to unite as part of the AGC to enable amphibian genomics research to "leap" to the next level.
ABSTRACTThe Eastern Arc Mountains (EAM) and Coastal forests of Tanzania are renowned for harboring large number of threatened and endemic vertebrate species, yet most of these areas have been partially studied. The Kimboza Nature Forest Reserve (KNFR) is a small forest which is in transition between the EAM and Coastal forests, and among the poorly surveyed areas for amphibians and reptiles. We conducted systematic surveys across the KNFR in 2012 and between 2020 and 2023 using a range of approaches with the aim of establishing a comprehensive and updated list of reptile and amphibian species and assess the contribution of EAM and Coastal forests to the KNFR's herpetofauna. We identified 77 species, 29 amphibians and 48 reptiles, substantially updating previous species lists. Three of these species (Kinyongia magomberae, Trachylepis boulengeri and Philothamnus macrops) represent range extensions from previously known ranges. Fourteen species are endemic to East Africa, 11 of them being restricted to Tanzania. These results make the KNFR the richest forest reserve for herpetofauna per square km in Tanzania, and most similar in its composition to the Coastal, rather than Eastern Arc forests. With the caveats concerning taxonomic uncertainties and the inequalities of sampling intensity across the region, this study shows that the KNFR is an important area that deserves conservation attention. The KNFR, like other Coastal forests, is under significant pressure from anthropogenic activities which call for an urgent action to protect this small but rich forest.
Discoveries of new species can greatly impact our understanding of the biogeography of a region. For example, groups of amphibian lineages restricted to the Afrotemperate forests of Tanzania and Ethiopia are indicative of a shared biogeographical history of this highly discontinuous ecosystem. Curiously, many of these lineages are absent from the geographically intermediate Kenyan highlands. This phylogeographical interval is generally considered to be attributable to the younger, volcanic origins of much of the Kenyan highlands, and thus an amphibian fauna that is derived largely from recent colonization events rather than comprising older relicts. Contrasting with this view, here we report on the discovery of a single specimen of Bufonidae (true toad) from Mount Kenya. The specimen belongs to a species new to science and deserves recognition at the generic level owing to its notable molecular phylogenetic and morphological divergences from other described taxa. It is most closely related to the Tanzanian genera Churamiti and Nectophrynoides. The discovery of this new toad and its association with Afrotemperate species is significant because it links Kenya to the biogeographically more ancient Tanzanian mountains and supports the potential longevity of the Afrotemperate forests in Kenya. Broadly, it highlights that we are still adding major branches to the phylogeny of anurans.
Facultative colour change is widespread in the animal kingdom, and has been documented in many distantly related amphibians. However, experimental data testing the extent of facultative colour change, and associated physiological and morphological implications are comparatively scarce. Background matching in the face of spatial and temporal environmental variation is thought to be an important proximate function of colour change in aquatic amphibian larvae. This is particularly relevant for species with long larval periods such as the western spadefoot toad, Pelobates cultripes, whose tadpoles spend up to six months developing in temporary waterbodies with temporally variable vegetation. By rearing tadpoles on different coloured backgrounds, we show that P. cultripes larvae can regulate pigmentation to track fine-grained differences in background brightness, but not hue or saturation. We found that colour change is rapid, reversible, and primarily achieved through changes in the quantity of eumelanin in the skin. We show that this increased eumelanin production and/or maintenance is also correlated with changes in morphology and oxidative stress, with more pigmented tadpoles growing larger tail fins and having an improved redox status.
The spiny-throated reed frog species group is a small radiation of Hyperolius frogs from East Africa. Unlike many members of the genus which have relatively wide distributions, these species tend to be small-range endemics found in montane and submontane forests. Recent discovery of a golden-hued frog with the clade-specific traits of spines on their gular discs prompted a morphological and genetic exploration of the distinctness of this new lineage and relationships to other members of the clade. Genetic (mitochondrial and nuclear loci) results resolved many sister-relationships, but deeper nodes in the phylogeny were poorly resolved. A reduced-representation genome-wide Single Nucleotide Polymorphism (SNP) dataset was able to fully resolve the phylogenetic relationships within this clade, placing this new lineage, here named after the mountain range in which is it found-H. ukaguruensis sp. nov., as an early diverging lineage within the group. This new species is distinct from all other spiny-throated reed frogs, necessitating further understanding as a single-mountain endemics vulnerable to habitat loss and potential decline. Morphometric analyses identify clear morphological characteristics that are distinct for the herein described species, most noticeably in that the eyes are significantly smaller than other members of the genus for which we have samples.
Human modification of the environment has drastically changed ecosystems around the globe. While forest-loss (deforestation) has been well studied for its effects on ecosystems, afforestation also has major impacts. The Udzungwa Plateau in Tanzania is naturally a mix of forests and grasslands. However, non-native pine plantations have recently increased in the area displacing the native grasslands of the montane plateau. In this study, we explored the effects of land use change on amphibian communities by comparing amphibian surveys before non-native plantations were introduced (similar to 2000) and after (2017-2019). To put these amphibian surveys into wider context across the plateau and to distinguish local population loss compared to plateau-wide extinctions, we sample diversity at new sampling locations and locations with multiple surveys through time. We then assessed landscape change through remotely sensed data and ground surveys. Amphibian encounter surveys found approximately the same species diversity across all sampling locations, but local extinctions appear likely. Remaining amphibians appear to be limited to small refugia in non-pine wetlands. Approximately half (45%) of the species found have limited distributional ranges (<72,000 km(2)) and are described as habitat specialists by the IUCN Red List. Monitoring pine plantation growth using remote sensing techniques suggested only limited extensions of plantations between 2000 through to 2013-2016, but ground surveys found small pines (<3 years old) throughout almost all areas identified as grasslands on satellite imagery. Our study highlights the plight of this narrowing biome on the African continent and calls for more research on the impact of non-native plantations on natural communities.Abstract in Swahili is available with online material.
Habitat encroachment can have devastating effects upon biodiversity, especially amphibians. Phyllobates vittatus is an endemic frog from Costa Rica, where land cover has seen significant changes over recent decades. Here we use remote sensing to create a land cover map of the region and carry out ecological niche modelling to identify the main abiotic factors associated to the distribution of this species. We have informed our models based on our own field observations, those from other researchers, and citizen science participants to obtain a comprehensive database of P. vittatus occurrences. Elevation, forest percentage, distance to lakes and rivers, annual temperature range and precipitation variables were found to shape the ecological niche of P. vittatus, which is mostly located within protected areas. Prior knowledge of the habitat of the species was key to interpret the model output. We identify populations that might be isolated, and areas where presence has not yet been verified or that have not been occupied by the species, thus, identifying potential areas for reintroductions. We also calculated the area of occupancy and recommend that P. vittatus' status be adjusted to "Endangered". Future surveys and evaluation of population health and connectivity would help to better ensure the protection of the species in the long-term.
Genomic resources for amphibians are still hugely under-represented in vertebrate genomic research, despite being a group of major interest for ecology, evolution and conservation. Amphibians constitute a highly threatened group of vertebrates, present a vast diversity in reproductive modes, are extremely diverse in morphology, occupy most ecoregions of the world, and present the widest range in genome sizes of any major group of vertebrates. We combined Illumina, Nanopore and Hi-C sequencing technologies to assemble a chromosome-level genome sequence for an anuran with a moderate genome size (assembly span 3.09 Gb); Pelobates cultripes, the western spadefoot toad. The genome has an N50 length of 330 Mb with 98.6% of the total sequence length assembled into 14 super scaffolds, and 87.7% complete BUSCO genes. We use published transcriptomic data to provide annotations, identifying 32,684 protein-coding genes. We also reconstruct the P. cultripes phylome and identify 2,527 gene expansions. We contribute the first draft of the genome of the western spadefoot toad, P. cultripes. This species represents a relatively basal lineage in the anuran tree with an interesting ecology and a high degree of developmental plasticity, and thus is an important resource for amphibian genomic research.
Records of biodiversity over time are important resources for assessing conservation priorities. However, such baseline data are missing for regions of key biodiversity importance. The Eastern Arc Mountains of Tanzania are known for their species richness and endemism, but not all mountain blocks have received the same attention. The Ukaguru Mountains, for example, have only infrequently been surveyed by herpetologists, with the first known herpetological survey in 1990. Here we compile and quantify all amphibian survey efforts in the Ukaguru Mountains in the past 30 years, publish an updated species list and comment on the health of amphibian populations and their habitat. We report on fourteen described species of amphibians, with potentially three additional species awaiting formal description. Of these seventeen lineages, seven are endemic to the Ukaguru Mountains. Although total species numbers remain low, compared with other Eastern Arc Mountains, surveys frequently recorded new species for the Ukaguru Mountains and for science. Worryingly, however, endemics, such as the monotypic bufonid Churamiti maridadi, have not been recorded in the past fifteen years. Our analyses show the region is becoming warmer and drier and is experiencing an alarming rate of deforestation. We find that over the past 30 years, dense forest cover inside the boundaries of the forest reserves has reduced by 8.4%.
Amphibians have undergone important evolutionary transitions in reproductive modes and life-cycles. We compare large-scale macroevolutionary patterns in these transitions across the three major amphibian clades: frogs, salamanders, and caecilians. We analyse matching reproductive and phylogenetic data for 4025 species. We find that having aquatic larvae is ancestral for all three groups and is retained by many extant species (33–44%). The most frequent transitions in each group are to relatively uncommon states: live-bearing in caecilians, paedomorphosis in salamanders, and semi-terrestriality in frogs. All three groups show transitions to more terrestrial reproductive modes, but only in caecilians have these evolved sequentially from most-to-least aquatic. Diversification rates are largely independent of reproductive modes. However, in salamanders direct development accelerates diversification whereas paedomorphosis decreases it. Overall, we find a widespread retention of ancestral modes, decoupling of trait transition rates from patterns of species richness, and the general independence of reproductive modes and diversification.
The spectral characteristics of vertebrate ocular lenses affect the image of the world that is projected onto the retina, and thus help shape diverse visual capabilities. Here, we tested whether amphibian lens transmission is driven by adaptation to diurnal activity (bright light) and/or scansorial habits (complex visual environments). Spectral transmission through the lenses of 79 species of frogs and six species of salamanders was measured, and data for 29 additional frog species compiled from published literature. Phylogenetic comparative methods were used to test ecological explanations of variation in lens transmission and to test for selection across traits. Lenses of diurnal (day-active) and scansorial (climbing) frogs transmitted significantly less shortwave light than those of non-diurnal or non-scansorial amphibians, and evolutionary modelling suggested that these differences have resulted from differential selection. The presence of shortwave-transparent lenses was common among the sampled amphibians, which implies that many are sensitive to shortwave light to some degree even in the absence of visual pigments maximally sensitive in the UV. This suggests that shortwave light, including UV, could play an important role in amphibian behaviour and ecology. Shortwave-absorbing lens pigments likely provide higher visual acuity to diurnally active frogs of multiple ecologies and to nocturnally active scansorial frogs. This new mechanistic understanding of amphibian visual systems suggests that shortwave-filtering lenses are adaptive not only in daylight conditions but also in those scotopic conditions where high acuity is advantageous. Read the free Plain Language Summary for this article on the Journal blog.
That hardcoded genomes can manifest as plastic phenotypes responding to environmental perturbations is a fascinating feature of living organisms. How such developmental plasticity is regulated at the molecular level is beginning to be uncovered aided by the development of -omic techniques. Here, we compare the transcriptome-wide responses of two species of spadefoot toads with differing capacity for developmental acceleration of their larvae in the face of a shared environmental risk: pond drying. By comparing gene expression profiles over time and performing cross-species network analyses, we identified orthologues and functional gene pathways whose environmental sensitivity in expression have diverged between species. Genes related to lipid, cholesterol and steroid biosynthesis and metabolism make up most of a module of genes environmentally responsive in one species, but canalized in the other. The evolutionary changes in the regulation of the genes identified through these analyses may have been key in the genetic accommodation of developmental plasticity in this system.