Common Seamoth

The fish family Pegasidae, the “sea moths”, includes just five species (placed in two genera) but is represented in temperate and tropical coastal zones throughout the Indo-Pacific. All sea moths are small (no more than than ~180 mm total length), benthic (bottom-dwelling), and very well camouflaged. They commonly occur in relatively shallow coastal waters in open sand or mud substrate in calm areas. (Palsson and Pietsch 1989, cited in Pajaro et al. 2004) The Short Dragonfish (Eurypegasus draconis) is the most widely distributed pegasid, occurring throughout the tropical and subtropical Indian Ocean, Red Sea, and western and central Pacific. It is one of several pegasid species that can be found in bays and estuaries. The maximum recorded length is 77 mm. This species has been collected from depths as shallow as 3 m or less, but usually occurs between 37 and 91m (Palsson and Pietsch 1989, cited in Herold and Clark 1993). Herold and Clark (1993) studied this species in the field (in the Red Sea) and in captivity. They found E. draconis at depths between 1.1 and 18.3 m in areas where coastal coral reefs were disrupted by channels and lagoons and where the bottom consisted of sand and rubble, sometimes with the seagrass Halophila stipulacea, and only occasionally with patches of corals. The authors noted in their observations that individual fish were able to change color to match their background. During the day, fish crawled slowly over the seafloor using their pelvic fins alternately, swimming only if disturbed. They became inactive after sunset and did not resume crawling until after sunrise. To feed, these fish moved their snouts very close to the food. The mouth would then protrude forward and downward, producing an inhalant current that sucked the food item into the mouth. Analysis of stomach contents revealed isopods, isopod eggs, decapod larvae, harpacticoids, copepods, copepod larvae, goby eggs, and stones up to 1 mm in diameter. Polychaetes, nematodes, trematodes, Alpheus (pistol) shrimp, post-veliger mollusks, and foraminiferans were also found. A curious behavior seen in these fish is that they sheds their skins in one piece, probably every one to five days, a process described in some detail by Herold and Clark (1993). Herold and Clark (1993) also discuss evidence suggesting monogamy in this species, as well as other aspects of social and reproductive behavior. Although sea moths are not harvested for food, Vincent (1997) estimated that millions of sea moths are sold for traditional medicine each year in China and Hong Kong alone, with supplies coming from China, Vietnam, and possibly other areas in Southeast Asia. Live sea moths are sold in the aquarium trade. Pajaro et al. (2004) studied the sea moth fishery in the Philippines, which involves both Eurypegasus draconis and Pegasus volitans. This trade includes both dead fish (taken mostly as bycatch but sold for the traditional medicine trade) and live fish for the aquarium trade. Although the sea moth fishery was not of great economic significance, the very substantial numbers of fish taken may have a seriously negative impact on populations in the Philippines. (Herold and Clark 1993; Pajaro et al. 2004)

Color in life variable; body usually light to dark brown, with dorsal and lateral area darker than ventral surface. Pectoral fins hyaline, distal margin white and spotted. Pelvic fin spine and 1st ray forming an elongate, tentacular structure. 3 pairs of dorsolateral body plates; 4 pairs of ventrolateral body plates; tail rings 8 (rarely 9), mobile. A pair of deep pits posterior to orbit. Suborbital shelf concave, eye visible in ventral view. Ventral ridges of rostrum greatly expanded than dorsal ridges, each with laterally directed denticles. Anal papilla absent.Description: Characterized by relatively broad and short body carapace; relatively short snout (Ref. 90102).

Are broadcast spawners. In several aquaria, spawning is observed as pairs rose to about 50 cm above the substrate, their ventral surfaces closely opposed, releasing gametes at the apex of their upward rush; then they glided down to the bottom. As the pairs landed on the substrate, the male continued to follow his mate. Release of gametes follows. Spawning occurred only within pairs (obligate and genetic monogamy) (Ref. 52884).

Dorsal spines (total): 0; Dorsal soft rays (total): 5; Analspines: 0; Analsoft rays: 5; Vertebrae: 19 - 22

Inhabit lagoons often among algal or seagrass beds (Ref. 5503). Found on sand or silt bottoms, frequently in bays or estuaries (Ref. 3132). They are opportunistic feeders that collect mainly epifaunal and interstitial invertebrate prey, e.g., crustaceans and worms from the sediment-water interface (Ref. 9137).

Inhabit lagoons often among algal or seagrass beds (Ref. 5503). Found on sand or silt bottoms, frequently in bays or estuaries (Ref. 3132). They are opportunistic feeders that collect mainly epifaunal and interstitial invertebrate prey, e.g., crustaceans and worms from the sediment-water interface (Ref. 31134). Shed their skin in one piece with a rapid jump periodically to rid themselves of accumulated ballast (Ref. 31134). Adults usually in pairs on muddy substrates (Ref. 48635). Has a monogamous mating system with close-pair bonding (Ref. 90102).

分布於印度-太平洋海域，西起紅海、南非等地，東至馬貴斯及社會群島，北部日本，南至澳洲海域。臺灣分布於西南部及東北部海域。

小型魚類，偶為底拖網捕獲，除學術研究外，一般皆以下雜魚處理，不具食用價值。

體縱扁而寬，完全被覆堅硬骨板，包括背部側3節、腹部側4節以及可移動之尾環8或9節；最後尾環背面具棘。枕部具2凹窩。眼上骨突出，眼間隔凹入；由腹面可見眼晴。吻部之腹面較背面寬大，稜脊具鋸齒狀。無肛門乳突。背鰭位於體後，與臀鰭相對，無硬棘，僅具5軟條；胸鰭大形，呈水平翼狀，具透明鰭膜以及9-12不分枝軟條；腹鰭具I棘，第一軟條延長呈觸手狀。體色多變，通常淡褐至深褐色，背部和側邊顏色深於腹面；胸鰭具縱列斑點；尾鰭亦具數列黑色斑點。

主要棲息於具海藻床的潟湖區或沙洲海域，亦常出現於海灣或河口域。主要以小型無脊椎動物為食。成魚時，常出現於泥沙區水域。

The little dragonfish or short dragonfish (Eurypegasus draconis) is a species of marine fish in the family Pegasidae. It is widespread throughout the tropical waters of the Indo-Pacific, including the Red Sea.

The little dragonfish can grow up to 10 cm (3.9 in) length. It sheds its skin in one piece. Millions of these kind of fish are sold for traditional medicine each year in China and Hong Kong alone.

Inhabits lagoons often among algal or seagrass beds (Ref. 5503). Found on sand or silt bottoms, frequently in bays or estuaries (Ref. 3132). Feeds on minute invertebrates (crustaceans and worms).