Lamontichthys
Encyclopedia
Lamontichthys is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of catfish
Catfish
Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...

es (order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 Siluriformes) of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Loricariidae
Loricariidae
Loricariidae is the largest family of catfish , with almost 700 species and new species being described each year. Loricariids originate from fresh water habitats of Costa Rica, Panama, and tropical and subtropical South America. These fish are noted for the bony plates covering their bodies and...

. It includes four species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

, L. filamentosus, L. llanero, L. maracaibero, and L. stibaros.

Taxonomy

The phylogenetic
Phylogenetics
In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...

 position of Lamontichthys remains uncertain. It has been considered to be sister
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 to Harttia
Harttia
Harttia is a genus of catfishes of the family Loricariidae.-Taxonomy:As of 1997, Harttia was considered a monophyletic taxon. However, Harttia is in need of revision...

, whereas Lamontichthys shows much more similarities with Pterosturisoma microps
Pterosturisoma microps
Pterosturisoma microps is the only species of the monotypic genus Pterosturisoma, a genus of the family Loricariidae of catfish ....

of the monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 genus Pterosturisoma, which only differs from Lamontichthys by the number of pectoral fin rays.

Distribution and habitat

Lamontichthys is distributed in the northwestern part of South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 in the upper Amazon
Amazon River
The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...

 and Orinoco
Orinoco
The Orinoco is one of the longest rivers in South America at . Its drainage basin, sometimes called the Orinoquia, covers , with 76.3% of it in Venezuela and the remainder in Colombia...

 River drainages, and in the Lake Maracaibo
Lake Maracaibo
Lake Maracaibo is a large brackish bay in Venezuela at . It is connected to the Gulf of Venezuela by Tablazo Strait at the northern end, and fed by numerous rivers, the largest being the Catatumbo. It is commonly considered a lake rather than a bay or lagoon, and at 13,210 km² it would be the...

 region. Species in this genus occupy the same ecological niche
Ecological niche
In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; e.g. a dolphin could potentially be in another ecological niche from one that travels in a different pod if the members of these pods utilize significantly different food...

 as those of Harttia. They mainly live in the mainstream of rivers, on rocky and sandy bottoms. L. filamentosus originates from the western Amazon River basin. L. llanero is distributed in the Guanare Viejo River of the Orinoco River drainage. L. maracaibero frequently inhabits the well-oxygenated waters in the middle reaches of rivers of the Lake Maracaibo basin. L. stibaros is from high altitude habitats of the Bobonaza River
Bobonaza River
The Bobonaza River is a river of Ecuador. It drains into the Pastaza River, and ultimately into the Amazon River at Iquitos in Peru.Its course runs mostly through Amazonian tropical rainforest, much of which is still sparsely populated...

 basin.

Description

Sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...

 in Lamontichthys includes hypertrophied odontode
Odontode
Odontodes, or dermal teeth, are hard structures found on the external surfaces of animals or near internal openings. They comprise a soft pulp surrounded by dentine and covered by a mineralized substance such as enamel, a structure similar to that of teeth. They generally do not have the same...

s on the pectoral spines in mature males. In all species of Lamontichthys, there is one pectoral fin spine and seven pectoral fin rays on each fin, as opposed to the rest of Loricariinae species which have one pectoral fin spine and only six pectoral fin rays. Lamontichthys species grow to about 16.7–24.2 centimetre
Centimetre
A centimetre is a unit of length in the metric system, equal to one hundredth of a metre, which is the SI base unit of length. Centi is the SI prefix for a factor of . Hence a centimetre can be written as or — meaning or respectively...

s (6.57–9.53 in
Inch
An inch is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in a foot...

) SL
Fish measurement
Fish measurement refers to the measuring of the length of individual fish and of various parts of their anatomy. These data are used in many areas of ichthyology, including taxonomy and fisheries biology.-Overall length:...

.

Ecology

Lamontichthys is an open brooder; eggs are laid on an open surface such as rocks, submerged wood or plants, and are generally exposed to the current. Females lay a few large-sized (1.4–1.8 millimetre
Millimetre
The millimetre is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length....

s or .056–.071 in in diameter) yellowish eggs during each spawning event.
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