Nectophrynoides viviparus ( Tornier, 1905 )

Thrane, Christian, Lyakurwa, John V., Liedtke, H. Christoph, Menegon, Michele, Petzold, Alice, Loader, Simon P. & Scherz, Mark D., 2025, Museomics and integrative taxonomy reveal three new species of glandular viviparous tree toads (Nectophrynoides) in Tanzania’s Eastern Arc Mountains (Anura: Bufonidae), Vertebrate Zoology 75, pp. 459-485 : 459-485

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.

Figures

Figure 1. Maximum likelihood phylogeny of glandular tree toads inferred from the three mitochondrial markers (Nectophrynoides viviparus complex). ModelFinder recovered three partitions of the data (Partition 1: 12 S, 16 S - TPM 2 u, Partition 2: COI _ p 1, COI _ p 2 - HKY, Partition 3: COI _ p 3 - TIM 2). Branch supports refer to bootstrap values, and branch lengths represent the number of nucleotide substitutions per site (see scale bar). Nectophrynoides species not part of the N. viviparus complex are shown in grey, and type material for which sequence information was obtained via museomics are shown in orange. Heatmap inset shows mean uncorrected 16 S genetic pairwise distances.

Figure 4. Intraspecific variation within Nectophrynoides viviparus sensu stricto in life. A Adult female MTSN 9407; B adult MTSN 9406; C, D adult MTSN 9383. Photographs from Mdandu, Livingstone Mountains by Michele Menegon.

Figure 5. Habitat of Nectophrynoides viviparus sensu stricto in Mdandu, Livingstone Mountains F. R. Photograph by Michele Menegon.

Figure 6. Pulse train arrangement and frequency landscape of A Nectophrynoides viviparus sensu stricto from Mdandu, Livingstone Mountains; B N. uhehe sp. nov. from Uzungwa Scarp N. F. R., Udzungwa Mountains. Plots from top to bottom show: frequency spectrum (FFT function width = 128, linear scale, Hann Window); spectrogram; and waveform (pulse train). Spectrogram and waveform are shown over the duration of a call (0–0.35 s).

Figure 7. Comparative photographs of lectotype and holotypes. For each specimen, dorsal (left), lateral (centre), and ventral (right) views are shown. A Lectotype of Nectophrynoides viviparus sensu stricto (ZMB 21775); B holotype of N. luhomeroensis sp. nov. (BM 1983.6; KMH 2438); C holotype of N. uhehe sp. nov. (ZMUC R 131391; M 000044); D holotype of N. saliensis sp. nov. (MUSE 13758; KMH 26644). Scale bar: 10 mm.