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Tadpoles of the Asiatic torrent frog genus Amolops possess large abdominal suckers and a complex oral apparatus which allow them to adhere tightly to and also to move over wet rock surfaces, a morphology termed gastromyzophorous. Accounts of larval development, and overall sucker morphology and microstructure are patchy in this genus. Here, from a large sample (n = 90) of Amolops tadpoles collected from two sites in Nepal, we give a detailed description of the tadpoles' external morphology, including pigment pattern variation, and their development from soon after hatching to the approach of metamorphosis, including new features of their oral apparatus (tooth rows and labia). Using SEM, we describe ultrastructural details of the sucker's surface, especially microvillated cells of the friction areas. From stained sections, previously unreported arrays of elastin fibres are described from the distal margins of the suckers. Based on our phylogenetic analyses and tadpole morphology we conclude that our specimens belong to the recently described species, A. mahabharatensis. [ABSTRACT FROM AUTHOR]

Butachlor is the most commonly used herbicide on rice paddy fields in Asian countries. Paddy fields are habitats commonly used for reproduction by many species of amphibians. We examined the effects of butachlor on Bufotes viridis development. Amplectant pairs of B. viridis were kept in the laboratory in an aquarium overnight, and their spawn collected the next morning. Eggs were exposed to butachlor at different concentrations (0.1, 0.2, 0.8, 1, 2, 3.5, 7, 14µg/l), all lower than the concentration used in the area (rice paddy fields) by farmers. Eggs were allowed to develop to Gosner stage 24 and their developmental patterns compared with those reared in normal conditions (control). In order to examine whether jelly coats have a significant role in the protection of developing eggs from the toxin, another group of eggs were de-jellied and treated in the same procedure. The LC50 value of butachlor was calculated as 14µg/l and 7µg/l after 96h for jellied eggs and de-jellied eggs respectively. Butachlor lead to a range of external and internal body malformations. Butachlor concentrations of 2µg/l, 7µg/l and 14µg/l reduced embryonic growth and development. A high mortality rate and both internal and external abnormalities were observed at lower concentrations than used in fields, suggesting that butachlor can have significant negative effects on amphibians where this herbicide is used. [ABSTRACT FROM AUTHOR]

The reproductive strategy and embryonic development of Bufotes surdus annulatus from Fars Province, Iran, are described. Single stranded egg strings (clutch sizes 338-2019 eggs, mean 1032, n = 69) were generally laid in waterfilled depressions in gravel near the edge of rivers. Eggs were 1.4 mm (± 0.18 mm) in diameter with jelly coats of 0.17 mm (± 0.04 mm). Hatching occurred at Gosner stages 17-18; features such as dental formula, external gills, cement gland, hatching gland, and external ciliation pattern are described and found to be similar but not identical to those found in B. viridis. [ABSTRACT FROM AUTHOR]

There is growing concern that climate change will have significant impacts on environmental quality and natural resources including amphibians. Among some data available on the effects of temperature changes on anurans, most studies have concentrated on adult individuals, and information is lacking on the effects of changed temperatures on the developmental patterns of anurans, including Bufotes viridis. To identify the range of temperature tolerance in B. viridis, we studied the effect of five temperatures (8, 15, 18, 25, 30°C) on the growth and development of the eggs of this species. Egg masses of B. viridis were collected from its natural habitat and placed in a designed aquarium with heating and cooling systems supplying a range of temperatures between 0 and 40°C. Sizes were measured and developmental stages identified relative to age to the early feeding tadpole stage (Gosner stage 25) at increments of temperature. The numbers of abnormal embryos and larvae were recorded at every temperature and thermal tolerance was recorded. A direct correlation was found to exist between temperature and growth and developmental rates. The results also confirmed that the developmental rate decreases with decreasing temperature. Larvae at stage 25 showed a significant difference in length only between eggs incubated at 8 and 30°C, respectively. It is concluded that developing eggs have a temperature tolerance from 12 through 25°C, and temperatures outside this range will reduce their survival rate. [ABSTRACT FROM AUTHOR]

We describe the tadpole of the Tobago glass frog Hyalinobatrachium orientate tobagoense for the first time. Like the few other Hyalinobatrachium species tadpoles described so far, it lives hidden in sand and gravel at the bottom of stream beds. The tadpoles have relatively long tails and slender lightly pigmented bodies with tiny eyes. They appear to grow very slowly and hind limb buds were not developed in the six week old Gosner stage 25 individuals we describe. [ABSTRACT FROM AUTHOR]

Lithium carbonate is used as a standard treatment for manic depression. While researchers have investigated the teratogenic effects of lithium carbonate on embryos of various animals in later stages of development, very limited work has been done on the probability of effects at early stages of development. In this study, the teratogenic effect of lithium carbonate was investigated at earlier preimplantation through implantation stages of development of Balb/C mouse embryos. A therapeutic dose (i.e., 300 mg/kg b.w.) was injected into mice intraperitoneally on days 3.5, 4.5, 5.5, and 6.5 of pregnancy. Then, on day 15.5 of gestation, embryos were collected from the pregnant animals. Among the embryos, 71.7% were healthy, 10.7% resorbed, 3.1% showed lordosis, 8.1% were underdeveloped and 8.4% had eye malformations. Significant increases (P < 0.05) in the number of hepatic megakaryocytes and nucleated red cells were also observed among experimental embryos. Analysis of maternal serum proteins prepared from dissected animals showed a significant increase or decrease (P < 0.05) in the levels of serum proteins albumin, alpha2 globulin, beta globulin, and gamma globulin. This research on early developmental stages suggests that pregnant mothers need to be aware of possible teratogenic effects at early stages of pregnancy, although it has been thought that the egg envelope can prevent teratogens from entering. In this case, mothers may need to stop lithium carbonate treatment before they make a decision to become pregnant.