''Clinus acuminatus'', the sad klipfish, is a species of

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

in the family

Clinid Clinidae is a family of marine fish in the order Blenniiformes within the series Ovalentaria, part of the Percomorpha . Temperate blennies, the family ranges from the Atlantic, Pacific, and Indian Oceans, in both the Southern and Northern Hemis ...

ae. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Southern Africa Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number of ...

, where it occurs along the coast of

Namibia Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and ea ...

and

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

. It can reach a maximum length of TL and is

viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...

. The sad klipfish feeds on crustaceans.

Description

The sad klipfish reaches a size of about 13 cm. It has a slightly compressed body with a wedge-shaped snout. There are prominent tentacles above the eyes with short, flattened stalks, ending in short, simple branches. The dorsal fin is low and even, with the first spine being shortest. Colouration is variable; generally pale, from a light buff to light green, yellowish brown or grey, somewhat mottled and speckled with small white spots and generally a few darker mosaic-like or speckled dark brown bars on the body. Sometimes the ground colour is of a darker shade, often with irregular clusters of white specks along the base of the dorsal fin. The tips of fins and supra-orbital tentacles are vermilion. There is usually a dark spot on the shoulder, and two dark radiating bands from the eye backwards across the cheek, and often a thin band downwards just in front of the eye. These give the fish a “sad” appearance. Small juveniles are white with well-defined black cross-bars. This fish may be hard to distinguish from

Clinus heterodon ''Clinus heterodon'', the westcoast klipfish, is a species of clinid that occurs in subtropical waters of the Atlantic Ocean from Namibia to South Africa where it is a denizen of tide pools. This species can reach a maximum length of TL. Thi ...

which occupies a similar environment. The body shape is similar, but the sad klipfish has a larger head and lower dorsal fin profile, and ''C. heterodon'' does not show the mosaic-like bars.

Diagnostics

The

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

has 30 to 34 spines, followed by 5 to 7 rays. The

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

has 2 spines and 20 to 24 rays. The

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

has 12 to 13 rays, and the ventral fin has 1 spine and 2 to 3 rays. There are 1 to 2 gill rakers on the upper limb of the first gill arch and 4 to 6 on the lower limb. There are 16 abdominal

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic i ...

and 27 to 29 caudal vertebrae. The

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

has 2 to 4 vertical pores above the opercle, then single pores alternately above and below along the front part of the line. There are 4.5 to 6 times the body depth in the

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

, and 3.2 to 4 times the head length in the standard length. The head length is from 2.75 to 5 times the eye diameter. The length of the caudal peduncle is 20.5% to 33.5% of the head length, and its depth is 20% to 35% of the head length head length.

Habitat and distribution

The species occurs west of Algoa Bay subtidally to Lüderitzbucht, but is more common west of

Cape Point Cape Point ( af, Kaappunt) is a promontory at the southeast corner of the Cape Peninsula, a mountainous and scenic landform that runs north-south for about thirty kilometres at the extreme southwestern tip of the African continent in South Afri ...

. It is abundant on the littoral of the Cape Peninsula and common in rock pools in

Sea Point Sea Point (Afrikaans: ''Seepunt'') is one of Cape Town's most affluent and densely populated suburbs, situated between Signal Hill and the Atlantic Ocean, a few kilometres to the west of Cape Town's Central Business District (CBD). Moving from ...

. It can be found under rocks and ledges in intertidal rock pools.

Ecology

The sad klipfish feeds on crustaceans such as amphipods, isopods, and crabs. It is viviparous, with a sexual frequency of 36%-53% for females. The species inhabits shallow rock pools and may thus be under some pressure from coastal development and tourism in the eastern part of its range, but is more abundant in its western range and likely unimpacted there.

References

External links

{{Taxonbar, from=Q2785763 acuminatus Taxa named by Marcus Elieser Bloch Taxa named by Johann Gottlob Theaenus Schneider Fish described in 1801 Fish of Namibia Fish of South Africa