Groupers, Anthias, Soapfish, etc. (Serranidae)

Of all the members of the Serranidae family found in local waters, probably the most widespread and frequently encountered is the Black-Tip Grouper (Epinephelus Fasciatus).

Growing to a maximum length of around 40cm, the Black-Tip Grouper is easily distinguished by its overall red-ish/brown colouration with darker vertical solid or broken bars. There is a known variant of the species which is pale, to almost white on most of its body (with very faint vertical bars), with the exception of a portion of the head which retains the common colouration. This variant, although seldom seen, is present in the area.

The main characteristic, and the one from which it gets its common name, are the black tips of the dorsal rays which become more prominent as the fins are extended (this often happens as the fish is approached by a diver or other large animal).

As with most locally occurring members of the family, this species is primarily an ambush hunter which feeds mostly on small fish, but will generally attempt to grab anything that it considers edible, including small crustaceans, fish and molluscs.

Black-Tip Groupers are one of the most popular local species with divers, snorkellers and photographers due to both there abundance, bright colour and approachable nature.

Unlike many of its more timid relatives, the Black-Tip Grouper can easily be approached (slowly) to within a meter or so, allowing for some excellent photo opportunities.

The Blue-Spotted Grouper (Cephalopholis Cyanostigma) is one of the smaller, more reclusive species of Grouper found in local waters.

Growing to around 30cm in length it is fairly easy to identify with its overall brown/redish colouration with darker "mottled" patches on the head and body. The patches on the flank may become almost joined in places to form uneven vertical bars.
The most distinctive characteristic of the species, albeit one shared with a number of its relatives (and leading to much confusion during identification), are the small, dark-edged blue spots covering the body.

Although similar in size to many of its locally occurring relatives, the Blue-Spotted Grouper is generally more difficult to observe, often dashing for cover amongst rocks or corals when approached.

Due to this reclusive nature, it is difficult to determine how common, or otherwise, the species may be.
It likely occurs at most of the shallow reef areas such as those found around Koh Phangan, Koh Tao and Angthong Marine park, although its presence at the deeper offshore sites such as Sail Rock could be considered sporadic at best.

Reaching a maximum length of around 120cm, the impressive Brown-Marbled Grouper (Epinephelus Fuscoguttatus) is one of the largest Grouper species in the area, second only to the Malabar Grouper (Epinephelus Malabaricus) (although there has been at least one confirmed sighting of a Giant Grouper (Epinephelus Lanceolatus).

Although its size alone makes identification relatively easy, the Brown-Marbled Grouper has other characteristics which make it one of the more recognizable local Groupers.

Relative to its length, the Brown-Marbled Grouper is also very thick set compared to many of its smaller relatives.
It typically has a brown to yellow/brown overall colour with numerous small brown/black spots (particularly on the head and fore-body).

Clusters of these small spots merge in places to form dark patches, which in turn may group together to form a series of broken vertical bars along the body.

In common with many larger species of Grouper, the caudal fin is slightly rounded.
At the front of the fish is the characteristic cavernous mouth, lined with rows of small, backward pointing, needle-like teeth.

The Brown-Marbled Grouper can be found at both shallow, inshore reef areas such as Mae Haad/Koh Ma reef as all of the deeper offshore locations such as Sail Rock.

Despite its size, the Brown-Marbled Grouper is rather shy and can only be approached slowly and with as little noise as possible.

In most areas, it appears they lead a generally solitary life, with larger individuals appearing to occupy a specific, possibly overlapping, territory.
It is estimated that the largest specimens may reach an age of 40 years or more.

The Coral Grouper (Epinephelus Corallicola) is a common Grouper in local waters which is equally at home at both the deeper offshore sites and shallower inshore reef areas.

Growing to a maximum length of around 50cm, the Coral Grouper is reasonably easy to identify with its overall pale-dark greenish/brown colouration and numerous small dark spots on the body and fins. The dorsal, pelvic and caudal fins may often exhibit and pale narrow white margin

There are often 1 - 3 larger dark patches at the base of the pectoral fin, the foremost of which being the most prominent.

As with most other Grouper species (and many other fish species), the Coral Grouper has the ability to rapidly alter its skin pigmentation, allowing it to adopt a more patterned, blotchy appearance.

The head of this species is also generally more slender and flattened than the majority of locally occurring Grouper species.

Although this is a fairly timid species which often spends its time resting below overhanging rocks or in wall crevices, it is possible to observe and photograph if approached slowly and without too much movement and noise.

The Freckled Grouper (Cephalopholis Microprion) is a shy and elusive member of the Grouper family found in local waters.

Growing to a maximum length of around 25cm, it is an easily identified, albeit difficult to approach, species which is seldom found out in the open. Instead, it prefers locations offering plenty of shelter such as shallow coral reef or rubble areas.

The main distinguishing features of this species are the small blue, equally spaced spots found only on the redish/brown area from the snout to around the rear of the pectoral fins.

From this point, the colour changes significantly to a pale greenish/yellow which extends to the caudal peduncle, with the exception of the pectoral, pelvic and anal fins which retain a darker shade with a thin blue margin.

Although the Freckled Grouper is likely to inhabit most local dive and snorkelling sites, it is perhaps most frequently encountered around the shallower Koh Tao sites which offer plenty of shelter.

The Leopard Coral Grouper (Plectropomus Leopardus) is a reasonably common member of the Grouper family in local waters, although due to its reclusive nature, it is not encountered as often as many other species.

Reaching a maximum length of around 120cm, the Leopard Coral is one of the largest species in local waters.

They can be found at most locations, although appear to be most common at the Angthong Marine park and other similar inshore reef areas.

Although there numerous Grouper species with a similar physical appearance (not to mention a huge variety of similar common names), the Leopard Coral Grouper is characterized by its overall grey (various shades) to brown/olive body colouration with numerous small, dark-edge blue spots on the body and fins.

Although these blue spots are a feature shared with numerous other species, it seems that the presence of a blue ring around each eye is the distinguishing feature of the Leopard Coral Grouper.

Since the individuals featured in this section all have a distinctive blue ring around the eyes, i will continue to classify this species as Plectropomus Leopardus, however it is by no means certain as yet.

The Malabar Grouper (Epinephelus Malabaricus) is undoubtedly the largest Grouper species frequently encountered in local waters.

Growing to a maximum length of at least 1.5m, the Malabar Grouper is reasonably common at most of the deeper offshore locations such as Sail Rock and Chumphon Pinnacles, although it may venture into the shallower locations less occasionally.

Although Malabar Groupers have the ability to rapidly change their colour/pattern (a common trait amongst many fish species), their most common appearance is a mottled pale - dark grey colouration with numerous small dark spots on the body and fins.
They commonly have a number of large dark blotch markings which partially merge to form a series of broken, vertical bands and have a distinctly rounded caudal fin.

With few (if any) natural predators, adult Malabar Groupers are one of the region's apex predators and, as with most members of the Grouper family, the have has a cavernous mouth capable of engulfing most of the resident reef creatures in the area.

Despite their size, they tend to be wary of divers, particularly in large groups, however they may be approached to within a short distance if done so as slowly and quietly as possible.

The Red-Bar Anthias (Pseudanthias Rubrizonatus), belonging to the sub-family Anthiinae, is close relative of the frequently encountered Groupers of the sub-family Epinephelinae.

As with most members of its sub-family, the Red-Bar Anthias, at a maximum length of around 12cm, is significantly smaller than locally occurring members of the Grouper family.

Although a very common sub-family throughout the world's coral reefs, there appear to be very few species of Anthias in local waters.

The Red-Bar Anthias is unusual in that it appears to prefer relatively deep water (20m+) which, combined with its small size, means it is rarely encountered and easily missed.

The species has been confirmed at only a few locations such as Sail Rock, most notably around the south-facing side of the East Pinnacle, at a depth of between 25 - 30m.

A number of individuals live together in small aggregations known as "harems", in which a single dominant male aggressively defends its territory, typically consisting of mostly females and possibly one or two non-dominant males.

In common with many other reef dwelling species such as the Wrasses and many Damselfish, Red-Bar Anthias are protogynous hermaphrodites, which begin life as female, with the largest female changing to male in the event of the dominant male dying.

There exists clear sexual dimorphism between males and females, with males being significantly more colourful than females.

Male Red-Bar Anthias are easily recognised by their overall yellow/orange colouration which tends to be more intense at the head and less so posteriorly.
There may be pinkish areas, predominantly on the anterior side of the deep red bar (after which the species is named) and a pink line originating below the eye and terminating just behind the gill cover (operculum). This line is one of the few markings shared by both male and female, although it is more prominent on the male
The upper and lower edges of the caudal fin, and dorsal fin margin are blue whilst the pectoral and anal fins have a paler blue margin. A prominent red sub-margin is also present on the anal fin

The main anatomical feature that distinguishes the male from female is the presence of an elongated filament on both the upper and lower posterior edge of the caudal fin.

In contrast to the vivid colouration of the males, female Red-Barred Anthias are a more uniform orange/pink overall with translucent pectoral fins and mainly purple-ish coloured dorsal, pelvic and anal fins.
The caudal fin is partially translucent, with distinctive red/orange upper and lower posterior tips.

Two-Banded Soapfish (Diploprion Bifasciatum)