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The lined seahorse (''Hippocampus erectus''), northern seahorse or spotted seahorse is a species of fish that belongs to the Syngnathidae family. ''H. erectus'' is a diurnal species with an approximate length of and lifespan of one to four years. The ''H. erectus'' species can be found with a myriad of colors, from greys and blacks to reds, greens, and oranges. The lined seahorse lives in the Atlantic Ocean as far north as Canada and as far south as the Caribbean, Mexico, and Venezuela. It swims in an erect position and uses its dorsal and pectoral fins for guidance while swimming. Lined seahorses feed mainly on minute crustaceans and brine shrimp, which they suck in through their snout. They are able to suck their prey by creating a current of water leading directly into its snout. Since seahorses are weak swimmers, they must ambush their prey by blending into their surroundings, which they do rather easily. The lined seahorse's eyes can move independently of one another, allowing it to effectively scan its surroundings. The species is sexually dimorphic and it is easy to distinguish between a male and female lined seahorse. The males are larger and also have longer tails. The lined seahorse is monogamous and performs ritual dances every morning to reestablish the bond with its mate. In addition, they create clicking sounds while embracing their partner. This action occurs when they initially find their mate. The intensity of their bond is also conveyed in how they handle the death of their partner: If either the male or female should die, the mate does not automatically replace the deceased mate with a new one. Often, it fails to find a new mate in its short lifespan. Like with other seahorses, the male lined seahorse is the caregiver. During intercourse, the female sprays her eggs into the male's brood pouch where the eggs will incubate for 20–21 days. When the juveniles are ready to hatch, the male attaches its tail to a stationary structure and begins to arch its back, back and forth, releasing the juveniles into the water column. The juveniles are approximately 11 mm at birth. They quickly begin to learn and mimic the behavior of its parent. Courtship between the male and female parents begin immediately after birth. The habitat of the lined seahorse is diminishing due to coastal growth and pollution, which ultimately is the cause of the decreasing population. The lined seahorse is also used as Chinese medicine and is common in the aquarium trade, contributing to its "vulnerable" status. ==Description== The lined seahorse was first named ''Hippocampus Erectus'' by George Perry in 1810. "Hippocampus" translates into "horse or sea monster" in ancient Greek.〔 The lined seahorse is a diurnal species that ranges in length from 12 cm to 17 cm; the maximum length reported for the species is 19 cm. The lined seahorse is sexually dimorphic, meaning there are distinct differences in appearances of males and females; most notably the brood pouch located on the male's abdomen which it utilized in reproduction. Males are also slightly larger in size and have longer prehensile tails than the females. In the wild, the lined seahorse has a lifespan of one to four years; however, in captivity their lifespan usually reaches the full four years. Four years is the maximum age reported for the species.〔(【引用サイトリンク】 Lined Seahorse )〕 They have a broad color spectrum, ranging from black, grey, brown, and green, to orange, red, and yellow. They tend to be paler on their front side.〔 However, their colors change due to altercations in their environment, diet, anxiety or stress level, and/or mood. The lined seahorse is brawny and upright in appearance. They have an armor-like body composed of approximately fifty bony plates. Together these bony plates form the outer skeleton of the species. It is common for the species to have white lines outlining the neck area—hence its common name, "lined seahorse"—and for tiny white dots to be present on the tail. The prehensile tail consists of numerous rings and the first, third, fifth, seventh, and eleventh may protrude farther outward than the remaining. The prehensile tail following the bony plates is utilized by the seahorse to grasp onto its environment composed of seaweed and coral. The tail curls forward and is seldom aligned. When a lined seahorse is very young (two weeks to four weeks), the tail is extremely limber. The snout length is approximately half the head length of the lined seahorse. The cheek spines, located diagonally down from the eye on either side may be single or double. In total, the lined seahorse has eleven trunk rings, 34–39 tail rings, 16–20 dorsal fin rays, and 14–18 pectoral fin rays. The pectoral fin is level with the eye on each back side of the lined seahorse's head. The dorsal fin is located on the back of the skeleton and is level with the stomach–chest area. Female dorsal fins are slightly larger than the male's and are located lower on the back. The eyes of the lined seahorse can concentrate together, or they can operate independently of one another. The lined seahorse may be considered sexually mature as early as four months; however, it is typically about eight months. The minimum size of a sexually mature lined seahorse is 5.6 cm.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lined seahorse」の詳細全文を読む スポンサード リンク
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