Editorial Type:
Article Category: Other
 | 
Online Publication Date: 01 Mar 2013

Reproductive Ecology of Quasipaa verrucospinosa (Bourret, 1937): Living in the Tropical Rain Forests of Central Vietnam

,
, and
Page Range: 138 – 147
DOI: 10.1670/11-286
Save
Download PDF

Abstract

Quasipaa verrucospinosa, the Granular Spiny Frog, is a discoglossid frog endemic to Vietnam and known only from its original description. We report the discovery of three populations of this species and describe the reproductive, fat body, and liver mass cycles for males and females. Results showed that males reached sexual maturity at 98.36 mm snout–vent length (SVL) and an age of nine months. Females reached sexual maturity at 109.45 mm SVL and an age of 11 months. Testes of males began to increase in volume in late June, and maximal testicular activity occurred from September to December. Testis size began to decrease in January and was smallest in April. Histological analyses revealed that sperm were not present throughout the year, indicating discontinuous reproductive activity for adult males. Reproductive females were observed only during the main rainy season months, indicating that females reproduce seasonally. The gonads of females began to increase in volume in July and maximal egg production occurred during the main rainy season (September to December). Females started to lay their eggs in July, and there were significant differences among mean clutch size and numbers of oviductal eggs or yolked follicles, vitellogenic follicles, and nonvitellogenic follicles. Clutch size was correlated significantly with female SVL and varied between seasons and months. The results of multiple regression analyses indicated that precipitation, but not temperature, was associated positively with testicular and ovarian volume.

Copyright: 2013
<sc>Fig. 1. </sc>
Fig. 1. 

Map of Thua Thien-Hue Province showing the geographic location of the three localities where specimens (circles) of Quasipaa verrucospinosa were obtained: (1) Mang Stream in Bach Ma National Park; (2) Ba Rang Stream in Nam Dong District; (3) Dong Ngai Stream in Aluoi District.

<sc>Fig. 2. </sc>
Fig. 2. 

Monthly mean precipitation and temperature in the study area. Data correspond to the monthly mean precipitation (solid lines, in millimeters) and air temperature (broken lines, in °C) over the last 20 years (Nguyen et al., 2004). Thua Thien-Hue (filled circles), Aluoi District (open circles), and Bach Ma-Nam Dong (filled triangles).

<sc>Fig. 3. </sc>
Fig. 3. 

Distribution of snout–vent length (SVL, mm) of the individuals in the different categories considered in the population of Quasipaa verrucospinosa. Juveniles of undetermined sex (gray bars), juvenile males (vertical lines bars), juvenile females (horizontal lines bars), adult males (black bars), adult females (white bars).

<sc>Fig. 4. </sc>
Fig. 4. 

Distribution of snout–vent length (SVL, mm) and sex of the individuals collected from the population of Quasipaa verrucospinosa. Reproductive adult males (filled circles), nonreproductive males (open circles), adult reproductive females (filled triangles), nonreproductive adult females (open triangles), juvenile males (filled squares), juvenile females (open squares), juveniles of undetermined sex (rhombuses). The arrows indicate the minimum size at sexual maturity for each sex.

<sc>Fig. 5. </sc>
Fig. 5. 

Male testis, fat body, and liver cycles of Quasipaa verrucospinosa. Data are mean (± 1 SD) residuals from a regression of log10-testis volume (cm3), fat body mass (g), and liver mass (g) against log10 SVL.

<sc>Fig. 6. </sc>
Fig. 6. 

Seasonal changes in testicular volume (A) and ovarian volume (B) of Quasipaa verrucospinosa in Thua Thien-Hue.

<sc>Fig. 7. </sc>
Fig. 7. 

Testicular histology (× 40) of Quasipaa verrucospinosa in Thua Thien-Hue. (A) Secondary spermatocytes and early spermatids abundant of stage 3; (B) spermatids transforming into a few spermatozoa of stage 4; (C) spermatozoa predominant and abundant of stage 6; (D) spermatozoa abundant, but spermatids and spermatocytes greatly reduced of stage 7 (Saidapur, 1983).

<sc>Fig. 8. </sc>
Fig. 8. 

Female gonad, fat body mass cycles, and liver mass of Quasipaa verrucospinosa. Data are mean (± 1 SD) residuals from a regression of log10-gonad volume (cm3), fat body mass (g), and liver mass (g) against log10 SVL.

<sc>Fig. 9. </sc>
Fig. 9. 

Relationship between log10 snout–vent length of males and testicular volume (A) with vertical scatter reflects seasonal variation; between log10 snout–vent length of females and clutch size (B) for Quasipaa verrucospinosa in Thua Thien-Hue.

<sc>Fig. 10. </sc>
Fig. 10. 

Living (A), euthanized (B), and surgical (C) specimens of Quasipaa verrucospinosa in the laboratory (SVL, snout–vent length; BW, body weight).

Contributor Notes

2 Corresponding Author. E-mail: biological99999@gmail.com
4

Deceased.

Accepted: 13 Feb 2012
  • Download PDF