Skip to content

Species

Esta categoria permite identificar las paginas de especies en INGLES

The species Chrysaora fuscescens is a jellyfish belonging to the class Scyphozoa. Its name comes from Greek mythology, where Chrysaor was the son of Poseidon and Medusa, whose name means 'he who has a golden armament'. On the other hand, the term fuscescens means 'dark towards the light', alluding to the amber color of its bell, which becomes more reddish towards the edge.

Chrysaora fuscescens can be found in the shallow bays and harbors of the eastern Pacific Ocean, from Canada to Mexico. It has a preference for cold, shallow, nutrient-rich waters, and its peak density coincides with the end of summer.

The body of Chrysaora fuscescens, like that of most jellyfish, has a bell. This species can reach up to 60 cm in diameter. The bell is yellowish or reddish/brownish in color, with the color getting darker as we move towards the outermost part. At the edge of the bell, we will find 24 thin, slightly flattened and elongated (1 meter) dark reddish tentacles. In the central part of the bell, and on the inside, 4 arms decorated with whitish spirals emerge from the center. These buccal arms are longer than the tentacles on the edge of the bell, and can reach lengths of up to 3.5-4.5 meters. Therefore, these are specimens of considerable size, which can even reach up to 25 kg in weight.

If we have the opportunity to see a specimen of Chrysaora fuscescens, taking all possible precautions so that its tentacles do not sting us, it is worth observing the tentacles and especially the beginning of the buccal arms, since it is common to find juvenile specimens of crabs of the genus Cancer. These crabs establish a symbiotic relationship by which they obtain a formidable protection, and in return they deworm the jellyfish.

This is a species with a carnivorous diet, which captures a wide variety of zooplankton, crustaceans, salps, pelagic snails, small fish and their eggs and larvae, and other jellyfish. It uses specialized cells, called cnidocytes, present in its tentacles to capture and immobilize its prey. Lacking a great capacity for voluntary directional movement, Chrysaora fuscescens depends on extending its tentacles in the water and waiting for prey to make contact with them. Once captured, the tentacles fold to bring the food into the mouth cavity. And in the opposite direction, among the species that feed on Chrysaora fuscescens, we find several species of sea turtles, the sunfish (Mola mola) and the northern fulmar seabird (Fulmarus gaciatis).

The sting of humans by Chrysaora fuscescens, although not necessarily fatal and similar in intensity to the pain caused by a bee sting, can have serious effects in people sensitive to its toxin.

The reproduction of this jellyfish is complex and involves an alternation of generations between a sexual form (jellyfish) and an asexual form (polyp). Adult jellyfish release gametes into the water, where fertilization occurs. The zygote develops into a larva called a planula, which attaches to the substrate and forms a polyp. The polyp reproduces asexually by gemmation or strobilation, giving rise to small jellyfish called ephirae, which grow into adult jellyfish.


Photos:

The purple-striped jellyfish (Chrysaora colorata) is a large species (diameter up to 70 cm in length) found mostly off the coast of California. This species is easily distinguishable by its characteristic pattern of radial purple stripes, as well as a purple stripe on the edge of the bell. The bell of its body has eight slender but long tentacles on its edge. In the center of the bell are four very leafy oral arms, which can reach very considerable lengths - the largest specimen reported that I have been able to access in the literature sets the record for its length at 4.5 meters.

It is worth paying close attention if you have the opportunity to see one of these majestic jellyfish - be very careful because they are highly stinging. It is not uncommon to see juvenile crabs from genera Cancer among their tentacles, which find protection in the body of this jellyfish. In return, these crabs deworm the jellyfish of parasitic amphipods. Other species that we can frequently observe in association with Chrysaora colorata are juveniles of various species of pelagic fish.

The diet of Chrysaora colorata has been little studied. The available information mentions a varied diet consisting of zooplankton, invertebrates and fish eggs. These prey are captured thanks to specialized cells present mostly in its tentacles, called cnidocysts. These cells, at the slightest contact with any of their prey, fire a tiny harpoon, which captures and immobilizes the food, which is then transported to the mouthparts in the center of the bell. On the other hand, species such as the leatherback turtle (Dermochelys coriacea) or the sunfish (Mola mola) frequently prey on Chrysaora colorata.

Reproduction of Chrysaora colorata occurs through the release of gametes into the water, where external fertilization takes place. Fertilized eggs develop into planulae larvae that settle to the seafloor and develop into polyps. Polyps can reproduce asexually by strobilation or budding, producing small jellyfish called ephirae that grow into adults.


Photos:

The giant deep sea isopod (Bathynomus giganteus) is undoubtedly a unique species. This species belongs to the order Isopoda, that is, they are cousins of the ball bugs that we can find in our gardens. It lives on the seafloor of the cold and deep waters (300-2500 m) of the Western Atlantic Ocean, including the Gulf of Mexico and the Caribbean Sea. Bathynomus giganteus is the first of the described species within the genus Bathynomus, it was described in 1879 by the French zoologist Alphonse Milne Edwards after the isopod was found in fishermen's nets off the coast of the Dry Tortugas in the Gulf of Mexico. Historically it has been described from other oceans beyond the Atlantic, but today these reported species are recognized as other species within the genus Bathynomus.

Bathynomus giganteus is an unusually large species compared to what is usual within the order Isopoda. This is due to an effect known as avisal gigantism, whereby invertebrate animals that inhabit deep, cold waters tend to grow larger and have greater longevity. Its body is divided into three distinct regions: a head (cephalon), a thorax and an abdomen (pleon); and can reach a total length of between 19 and 36 cm, although specimens up to 50-76 cm in length have been reported. The eyes are triangular in shape, widely spaced, large in size and composed of a multitude of facets (up to 4,000 according to some publications). When light bounces off them, they have a highly reflective coating on the back, which causes them to glow brightly. This, together with their unusual gigantism, gives Bathynomus giganteus specimens a frightening appearance, although this is not at all consistent with their calm demeanor.

Bathynomus giganteus uses its 7 pairs of jointed legs to explore the vast and inhospitable expanses of the seafloor. It has two pairs of antennae on its front, one short and the other much longer. These antennae allow them to detect their food at great distances. The diet of Bathynomus giganteus consists mainly of bottom-dwelling debris, although they may occasionally prey on other live and generally slow-moving prey if given the opportunity. Approximately 50-60% of their diet consists of vertebrates remains, followed by 30% cephalopods, 10-20% decapods and 5-10% other smaller isopod species.

Reproduction of Bathynomus giganteus is by egg laying. Mature females develop a pouch known as a marsupium, where the eggs are stored until the young are ready to emerge as miniature adults, known as mancas, skipping a larval stage altogether. Females are many times larger than females of other isopods, yet carry approximately the same number of eggs in their marsupium. The eggs therefore show an increase in size that appears to be almost proportional to the increase in body size.


Photos:

The species Aurelia labiata is a type of jellyfish that belongs to the group of cnidarians, in the family Ulmaridae. Its common name is moon jellyfish, due to the rounded and translucent shape of its bell, reminiscent of the satellite. Unlike other jellyfish, it does not have long, dangling tentacles, but rather a thin fringe around the edge of the bell and four oral arms extending from the base of the manubrium, the central organ containing the mouth and stomach. The bell has 16 recesses corresponding to the 16 sensory organs called ropalia, which allow it to perceive light, movement and balance. The bell can measure from 10 to 45 centimeters in diameter, and is usually milky white, sometimes with pink, purple, peach or blue shades.

The distribution of the species Aurelia labiata involves the coastal regions of the Pacific Ocean, from San Diego, California, to the Gulf of Alaska. It is a pelagic species, living in open waters, but is also found in bays and harbors, where it is more abundant. It can tolerate a wide range of temperatures, from -6ºC to 31ºC. It feeds mainly on plankton, small crustaceans and fish larvae, which it captures with its stinging cells and brings to its mouth with its oral arms. It can also absorb nutrients directly from the water through its epidermis. Aurelia labiata has adaptive behaviors that include directional and vertical swimming. Directional swimming helps it escape predators, approach a food source, or pass through turbulence. Vertical swimming allows it to avoid rocky walls and low salinity. These behaviors are based on its sensory receptors and diffuse nervous system, which give it greater mobility for survival.

The life cycle of Aurelia labiata is complex, alternating between two phases: the sexual or jellyfish phase and the asexual or polyp phase. Jellyfish are dioecious, i.e. there are male and female individuals that produce gametes (sperm and eggs) in their gonads located in the manubrium. The gametes are released into the water and external fertilization occurs. The zygote develops into a ciliated larva called a planula, which attaches to the substrate and transforms into a cylindrical polyp with tentacles. The polyp reproduces asexually by gemmation or strobilation, giving rise to small jellyfish called ephirae, which separate from the polyp and grow to sexual maturity.

Aurelia labiata is considered an important species for the marine ecosystem, as it is part of the food chain and contributes to the flow of energy and matter. It also has a positive economic value for humans, as it is a tourist attraction in aquariums and marine museums. However, it can also have a negative impact, as it can cause irritation with its stings or compete with other species for food.


Photos:

Anthopleura xanthogrammica is a species of intertidal sea anemone in the family Actiniidae. It is also known as green anemone, giant tide anemone, green surf anemone or rough anemone. It is one of the largest and most colorful anemones that can be found along the coasts of the Pacific Ocean, from Alaska to Panama.

Anthopleura xanthogrammica has a cylindrical column that can reach a diameter of 17.5 cm and a height of 30 cm. The column is wider at the base to better attach to rocks. The surface of the column is smooth and lacks markings or bands. The oral disc is broad and flat, and can measure up to 25 cm in diameter. Around the oral disc are the short, cone-shaped tentacles, which are arranged in six or more rows around the oral disc. The tentacles may have sharp or rounded tips, and have stinging cells called nematocysts that they use to capture prey or defend themselves. The oral disc and tentacles have a bright green color when submerged in water, due to the presence of symbiotic algae and pigments in their tissues. When the anemone is out of the water, it closes and shrivels, and its color becomes darker or brownish.

Anthopleura xanthogrammica lives in the intertidal zone of Pacific Ocean waters, where it is exposed to the air at low tide and submerged at high tide. It prefers rocky or sandy habitats, where there is sufficient sunlight for its symbiotic algae to photosynthesize. It may also inhabit deep channels in more exposed rocky areas, or on concrete pilings in bays and harbors. It usually lives alone, but can sometimes be found in groups of up to 14 individuals per square meter. Anthopleura xanthogrammica is a sedentary species, which attaches itself to rocks with its basal disc. It can move slowly using its basal disc or by contracting its column, but usually remains in the same place. During low tide, it closes and protects itself with a mucous layer that prevents desiccation. At high tide, it opens and extends its tentacles to capture prey or receive sunlight.

The diet of Anthopleura xanthogrammica is based mainly on zooplankton, small crustaceans, molluscs and fish that it catches with its tentacles. It also receives nutrients from symbiotic algae living in its tissues, called zooxanthellae and zoochlorellae. These algae produce sugars and oxygen through photosynthesis, which are used by the anemone. In return, the anemone provides them with carbon dioxide, nitrogen and protection.

Anthopleura xanthogrammica is a solitary species, which does not tolerate the presence of other anemones of the same species or other species in its vicinity. If two anemones come into contact, they can start a tentacle war, in which they attack each other with their nematocysts to inflict damage or drive the rival away.

As for reproduction, Anthopleura xanthogrammica reproduces both sexually and asexually. Sexual reproduction occurs when anemones release gametes into the water, which fuse to form planktonic larvae called planulae. The planulae swim until they find a suitable substrate on which to settle and metamorphose into small anemones. Asexual reproduction occurs when anemones divide by binary fission or by budding. Binary fission consists of the anemone splitting into two identical individuals. Gemination consists of the anemone producing a lateral bud that separates and forms a new anemone.


Photos:

Within the phylum of echinoderms and the Echinoidea class, we find the Arbacioida order and the Arbaciidae family to which the black sea urchin or Arbacia lixula belongs. It is a species that inhabits the tropical and subtropical waters of the Atlantic Ocean and the Mediterranean Sea. In the Atlantic Ocean this species is present in the Azores, Madeira and Canary Islands, and is rather scarce on the African coasts. In the western Atlantic, it is only present on the Atlantic coasts of Brazil. It has a preference for shallow waters in rocky environments with depths not exceeding 50 meters, although in the first 10 meters of depth, especially in the intertidal zone, is where they are more frequent. Arbacia lixula has a great resistance to waves. As a curiosity it takes a force of about 5 kilos to release the specimen from the substrate in which they live. This strong fixation is due to the force exerted by the different ambulacral feet of the specimen that hold it firmly to the substrate. It is very common to find specimens of Arbacia lixula together with specimens of the species Paracentrotus lividus, the latter characterized by a smaller number of spikes and by being arranged in a much more disordered way.

The body of Arbacia lixula is hemispherical in shape, with a flattened basal part. They can reach 5-8 cm in diameter, and the figure can reach up to 12 cm in diameter if we include the barbs. Continuing with the barbs, they are all approximately the same length (~6 cm) and are always erect, arranged in a dense and uniform manner. The ventral part of the body has no spines and the mouth is surrounded by a smooth dark greenish skin. As for coloration, the specimens of Arbacia lixula are of a very intense black color. It has been observed that those specimens placed in very poorly lit environments, can change the color from the characteristic black to a very dark brown.

Arbacia lixula is a herbivorous species that feeds mainly on calcareous algae that grow on rocky surfaces, as well as small filamentous algae.

During the months of December and January is when the specimens of Arbacia lixula reproduce. This reproduction is sexual, and occurs through the release of the gonads of the male and female specimens into the water column, where fertilization occurs and planktonic larvae are formed that will be spread thanks to the currents. Curiously, the gonads of Arbacia lixula contain very high levels of a carotenoid pigment called astaxanthin. This compound is of interest from a biomedical point of view as it has been extensively described for its ability to prevent neurodegenerative diseases.


Photos:

Codium vermilara is a species of green algae (phylum Chlorophyta) found in the Mediterranean Sea, the Atlantic Ocean and the Black Sea. Commonly known as wig or candelabrum algae, it is characterized by a cylindrical thallus (a structure that in plants would resemble trunks and branches) about half a centimeter in diameter and is branched. The thallus is strongly attached to the rocky bottom at a single point. Specimens can reach up to 30 cm in height. The thallus is formed by cellular filaments that are arranged in the form of a mesh, giving it a vertical bearing. The ends of the thallus are blunt, slightly flattened and of a slightly lighter green color than the rest of the structures.

As for its habitat, Codium vermilara is found in rocky intertidal zones and shallow seabeds (exceptionally up to 25-50 meters deep), with no direct exposure to the sun. It is moderately tolerant of waves and currents, although it has a preference for calmer areas. During the winter and autumn, after storms, it is common to find fragments of this algae on the beaches.

Despite the velvety appearance of its surface, in the summer months, the increase in water temperature causes this algae to develop longer filaments, similar in appearance to filamentous algae, which, together with the accumulation of sediment on the specimen, will often cause the specimens to be partially or completely camouflaged in the rocky environment.

Regarding reproduction, Codium vermilara has separate sexes, however, both sexes are found in the same individual, in different regions (i.e. it is a monoecious species). The specimens develop zygotes that are released into the water column to be fertilize and generate the next generation of specimens. Asexual reproduction can also occur in Codium vermilara, usually by fragmentation and settlement of the fragment(s) on the rocky bottom.

Codium vermilara are frequently preyed upon by specimens of the urchin Paracentrotus lividus.

Codium vermilara is often confused with other species of the same genus, especially with Codium fragilis. The feature that will allow differentiation between these two species is the arrangement and frequency of branching of the thallus. Codium vermilara has a more random branching pattern and not as regular as Codium fragilis. Another distinctive feature is the branching region itself. The species Codium decorticatum and Codium tomentosum have flattened branches, while in Codium vermilara and Codium fragilis the branches do not have any flattening, but continue the cylindrical section of their thalli. In addition, Codium tomentosum can only be confused with Codium vermilara in the waters of the Atlantic Ocean, not being present in the Mediterranean or the Black Sea.


Photos:

The blenny Parablennius zvonimiri is a species native to the Mediterranean and Black Seas, living in shallow coastal waters (2-10 meters) and on rocky bottoms with dim lighting, on vertical walls or near caves.

The body of Parablennius zvonimiri is elongated (<7 cm), slightly flattened laterally, with a slightly rounded head and an obtuse rostrum. As is common in blennid species, the skin of Parablennius zvonimiri lacks scales, and instead secretes a mucous substance. The species is characterized by the presence of medium-sized, branched and irregularly shaped supraocular tentacles (usually followed by small filaments behind the tentacles), as well as somewhat smaller tentacles on the nares. It has a single dorsal fin, with the spiny region (12 spines) and the soft region (18 soft rays) of approximately equal height and separated by a deep notch. The anal fin runs from about half the length of the body to the caudal peduncle, and consists of 2 spines followed by 19-20 soft rays. The pectoral fins are elliptical in shape and consist of 14 rays. The pelvic fins have one spine and 3 soft rays and are located in a jugular position. The body is reddish-brown, with some vertical blue lines on the rostrum. There is a series of 5 to 7 white spots along the back, just below the dorsal fin. Also very characteristic is a black spot located on the caudal fin.

During the months of May to July is when Parablennius zvonimiri specimens reproduce. The males court the females to attract them to their nests by a rocking motion of the head from side to side. If they are successful, both go to the hole where they will lay their clutches by attaching them to the substrate with an adhesive filament. From then on, the male will be the only one in charge of taking care of the clutch. It is very common for a male to take care of the clutches laid by several females in his nest.

The diet of Parablennius zvonimiri is very varied, finding among its main prey small benthic invertebrates such as isopods, amphipods, small shrimp, copepods and small molluscs.


Photos:

Parablennius incognitus is a species of blennid that inhabits the waters of the Mediterranean Sea and the Atlantic Ocean from the Canary Islands, Azores and Madeira to the northern coasts of Spain. It is a species that, as usual in blennids, lives in shallow waters (less than 4 meters) and with rocky bottoms with abundant algae cover.

The body of Parablennius incognitus is elongated, reaching up to 6 cm maximum total length. It has a single dorsal fin, with the spiny region (12 spines) and the soft region (17 soft rays) of approximately equal height and separated by a deep notch. The anal fin runs from about half the length of the body to the caudal peduncle, and consists of 2 spines followed by 19 soft rays. The pectoral fins are triangular in shape and consist of 14 rays. The pelvic fins have one spine and 3 soft rays and are located in a jugular position. A feature that will allow us to differentiate between the other blennid species, in addition to the aforementioned dorsal notch, is the presence of tentacles above the eyes. In the case of Parablennius incognitus, it has two branched tentacles, which are much more developed in males than in females.

Other characteristic features of Parablennius incognitus are the absence of white spots at the base of the dorsal fin, the presence of 7 to 9 transverse bands on the flanks that take the shape of an hourglass and may usually be bordered by blue shades, and a large reddish spot bordered in blue/white behind the eyes. The body coloration of Parablennius incognitus can be variable, especially in male specimens during the breeding season, and may adopt yellow, red, brown, and/or green shades.

During the months of May to August is when the specimens of Parablennius incognitus reproduce. Males court females to attract them to their nests by means of a rocking motion of the head from one side to the other. If they are successful, both go to the hole where they will lay their clutches, attaching them to the substrate by means of an adhesive filament. From then on, the male will be the only one in charge of taking care of the clutch. It is very common for a male to take care of the clutches laid by several females in his nest.


Photos:

Belone belone is a species belonging to the Beloniformes order and the Belonidae family. It is a species found in temperate waters of the Atlantic Ocean (from Norway to Madeira and the Canary Islands), the Mediterranean Sea and the Black Sea. We will rarely observe specimens of this species in waters deeper than 5 meters, as it is a neritic epipelagic species that usually swims very close to the surface and rarely separates from it. If they feel harassed, they can make big jumps out of the water to escape from potential predators.

The body of Belone belone is very long (up to 100 cm), slightly compressed laterally, with large eyes and a terminal mouth like a long beak with the upper jaw somewhat shorter than the lower, and both equipped with conical teeth, especially visible in adult specimens and not so much in juveniles. None of the fins of Belone belone have spines, but all their rays are soft. The dorsal fin has between 16 and 20 rays and together with the anal fin (19-23 rays) are located in a very rear position inside the body, almost at the height of the caudal peduncle. The anal fin is slightly longer than the dorsal fin, and both are positioned opposite each other. The pectoral fins (11-14 rays) and pelvic fins are reduced. Finally, the caudal fin has a very pronounced slit shape, with the lower lobe slightly longer than the upper one. As for the coloration, the body has a greenish blue color in the dorsal part, and fades as we move to the flanks to acquire a silver / whitish color in the ventral area.

Considering the morphology of its mouth and especially the robust conical teeth, it is not surprising that the diet of Belone belone consists of small pelagic pisciforms, especially anchovies, herring and sardines.

During the months of May to June is when the Belone belone breed. Generally, the adult specimens remain in the open sea, and to reproduce they approach coastal waters. The eggs are attached to floating objects.

There are three subspecies of Belone belone, which differ mainly in the waters in which they live and in the maximum sizes reached. The three subspecies are:

  • Belone belone belone. This is the subspecies that lives from the coasts of France and from there to the north. It is the largest subspecies, reaching a maximum length of 100 cm.
  • Belone belone gracilis. It inhabits the northeast Atlantic Ocean and the Mediterranean Sea. Reaches maximum lengths of up to 70 cm.
  • Belone belone euxini. Native to the waters of the Black Sea and the Sea of Azov. It is the smallest subspecies of the three, with specimens not exceeding 56 cm in length.


Photos: