JODI J. L. ROWLEY(1,2,6), HUY DUC HOANG(3) , VINH QUANG DAU(4) , DUONG THI THUY LE(3)  & TRUNG TIEN CAO(5) 

1 Australian Museum, 6 College St, Sydney, NSW, 2010, Australia. 
2 School of Marine and Tropical Biology, James Cook University, Townsville, QLD, 4811, Australia. 
3 University of Science-Ho Chi Minh City, Faculty of Biology, 227 Nguyen Van Cu, District 5, Ho Chi Minh City, Vietnam. 
4 Institute of Ecology and Biological Resources, 18 Hoang Quoc Viet, Hanoi, Vietnam. 
5 Faculty of Biology, Vinh University, 182 Le Duan, Vinh, Vietnam. 
6 Corresponding author: E-mail: jodi.rowley@austmus.gov.au 

We describe a new species of Leptolalax from central Vietnam. Leptolalax firthi sp. nov. is distinguished from its congeners by a combination of the following characters: an absence of distinct dark brown or black dorsolateral markings; toes with rudimentary webbing and wide lateral dermal fringes in males and weak or absent lateral dermal fringes in females; most males with wide lateral dermal fringes on Finger II; medium size (26.4–29.2 mm in 21 adult males, 25.7–36.9 mm in 14 females); and near immaculate white chest and belly. The male advertisement call of the new species, consisting of 2–5 notes with a dominant frequency of 5.4–6.6 kHz (at 18.3–21.2º C) is also unique among Leptolalax species for which calls are known. Uncorrected sequence divergences between L. firthi and all homologous 16S rRNA sequences available were >10%. At present, the new species is known from montane evergreen forest between ~860–1720 m elevation in Kon Tum and Quang Nam Provinces. The extreme sexual dimorphism observed in L. firthi in terms of lateral dermal fringing, a morphological character often used to distinguish Leptolalax species, highlights the importance of ensuring interspecific comparisons in the genus are performed separately for each sex.

Key words: Bioacoustics, Kon Tum Plateau, Leptolalax firthi sp. nov., Southeast Asia, sexual dimorphism

For full article, please check here: zootaxa3321_5668_2012.pdf