Color performance of false clownfish, Amphiprion ocellaris, Cuvier was first examined at four color backgrounds (blue, green red, and white) for 4 wk, then all fish were transferred to a white background for another 4 wk to test whether the impact of background colors on fish skin could have a lasting effect when the environment colors are changed. The experiment was conducted in 10‐L rectangular plastic buckets with three replicates. Thirty fish were stocked in each bucket and three fish were randomly sampled from each tank in Weeks 1, 4, and 8. The color hue, saturation, and brightness were quantified using image analysis. In addition to the whole body analysis, each fish image was divided into ventral and dorsal parts to examine the body position‐dependent response. Furthermore, color differences among the dorsal fin, anal fin, ventral fin, and caudal fin were also quantified. Blue or green background enhanced red orange color on fish skin, whereas white background made fish color brighter. Irrespective of background color, the dorsal side of fish exhibited more red orange, but the color was less bright and less saturated than that of ventral side. Upper fins (dorsal and caudal fins) were more red orange in a blue background than in a white background. Transferring fish from colored backgrounds to a white background made the fish skin and fins brighter, the color of ventral body and ventral fins less saturated, and the bottom fins more yellow orange. The results indicate that blue or green background could strengthen the orange color, whereas white background made fish color less saturated but brighter. The impact of background on the performance of fish color is temporary and likely to disappear when environmental color changes.

This study evaluated the role of supplemented dietary carotenoids in regulating the skin color and pigments of the false clownfish, Amphiprion ocellaris. Three carotenoid types, such as astaxanthin, β‐carotene, and canthaxanthin, were added to the basal diet at four pigment doses (0, 20, 50, and 100 ppm). Carotenoid diets were feed for 5 wk and then withdrawn from the diet for three additional wk during an 8‐wk trial. The dose of each diet did not change the overall color hue, brightness, or saturation, but astaxanthin was the only carotenoid that enhanced red hue by the end of Week 5. The withdrawal of astaxanthin from the diet did not reduce the red hue, but reduced saturation. In contrast, the withdrawal of dietary β‐carotene or canthaxanthin reduced color saturation and brightness, but did not affect color hue. Dietary astaxanthin increased skin astaxanthin in Week 1 and skin zeaxanthin in Week 5. The withdrawal of astaxanthin escalated skin canthaxanthin and zeaxanthin by Week 8. Dietary β‐carotene suppressed skin β‐carotene, but enhanced skin zeaxanthin by Week 8. Although skin canthaxanthin was enhanced by dietary β‐carotene from Week 5 onward, dietary β‐carotene at 100 ppm maximized skin canthaxanthin by Week 8. Interestingly, dietary canthaxanthin suppressed skin canthaxanthin and zeaxanthin, but increased β‐carotene. This study suggests that astaxanthin has the potential to enhance the red hue on clownfish skin and its withdrawal from the diet did not fade the red hue of the skin.

Preliminary data are presented detailing the reproductive biology and culture requirements of three species of tropical prawn. Stenopus hispidus, Lysmata amboinensis and Lysmata debelius are commercially important to the ornamental aquarium trade and are targeted by collectors. Collection of these Crustacea can involve direct damage to coral reefs apart from the potential negative impact on the coral reef ecology. The present findings demonstrate that these prawns may be cultured using standard techniques developed for the commercial penaeid industry.

Although the crab-eating frog Fejervarya cancrivora is one of the most widely distributed species in Asian region, taxonomic relationships among different populations remain unclarified. In this study, we attempted to elucidate the taxonomic status of F. cancrivora from Indonesian and other Asian populations. Five populations of F. cancrivora from Selangor (Malaysia), Cianjur (Java, Indonesia), Trat (Thailand), Khulna (Bangladesh), and Makassar (Sulawesi, Indonesia) were morphologically observed and subjected to crossing experiments. Principal component and clustering analyses revealed that these five populations could be organized into three groups corresponding to three observed morphological types: a Selangor and Cianjur group (large-type), a Trat and Khulna group (mangrove-type), and a Makassar group (Sulawesi-type). The limited crossing experiments revealed that hybrids between Selangor females and Cianjur and Trat males developed normally, whereas hybrids between Selangor females and Khulna males showed incomplete gametic isolation. Histological observations of the testes of mature males revealed the presence of pycnotic nuclei in the hybrids between Selangor females and Khulna males in addition to normal bundles of spermatozoa. In contrast, no pycnotic nuclei were observed in the Selangor controls. Although meiotic metaphases in the controls were normal, those in hybrids showed several abnormalities, such as the appearance of univalents and an increase in rod-shaped bivalents. Based on our findings from the morphological observations and crossing experiments, we conclude that each of three identified types represents a distinct species. We propose that the large-type is F. cancrivora, the mangrove-type is F. moodiei, and the Sulawesi-type represents an undescribed species.