Macrouroidei

Macrouroidei
	Malacocephalus occidentalis
Systematics
Cohort :	Euteleosteomorpha
Sub-cohort :	Neoteleostei
	Acanthomorphata
	Paracanthopterygii
Order :	Cod-like (Gadiformes)
Subordination :	Macrouroidei
Scientific name
	Macrouroidei
	Garman , 1899

The Macrouroidei (sensu Endo, 2002) are a subordination of the cod-like fish (Gadiformes). It contains two families, the most species-rich within the order Gadiformes, the grenadier fish (Macrouridae) with almost 400 species and the Steindachneriidae family, which consists of only one species, Steindachneria argentea .

features

The most striking feature of the Macrouroidei is the absence of the caudal fin including the caudal fin skeleton. Instead, they have long “rat tails”. In English the grenadier fish are therefore called "rattail". Another synapomorphism is a transverse protrusion of the middle pelvis.

In the past, the Macrouroidei (sensu Markle, 1989) were defined more broadly, and the deep- sea cod (Melanonidae) with small caudal fins and the Euclichthyidae with the only species Euclichthys polynemus were added to the taxon. Synapomorphies were considered to be the presence of luminous organs and the loss of the joint between the epihyal and interopercular . The first-mentioned feature is now considered plesiomorphism , that is, as an original feature that has already arisen in the parent group . The second characteristic of the Macrouroidei (sensu Markle, 1989) is problematic because morphological differences between the four families suggest a polyphyletic origin.

Systematics

Steindachneria argentea

The Japanese ichthyologist Hiromitsu Endo drew up the following cladogram on the phylogeny of cod-like species. The deep sea cod are then the basal sister group of all other cod-like species, and Euclichthys polynemus is a basal member of the suborder Gaidoidei .

Cod-like

Melanonoidei

	Deep sea cod (Melanonidae)

Macrouroidei

	Grenadiers (Macrouridae)

	Steindachneriidae

Gadoidei

Euclichthyidae

	Deep-sea cod (Moridae)

	other codlike families

swell

Hiromitsu Endo: Phylogeny of the Order Gadiformes (Teleostei, Paracanthopterygii). Mem Grad Sch Fish Sci Hokkaido Univ. Vol.49, No.2, pages 75-149 (2002) ISSN 1346-3306
EO Wiley & GD Johnson (2010): A teleost classification based on monophyletic groups. In: JS Nelson, H.-P. Schultze & MVH Wilson: Origin and Phylogenetic Interrelationships of Teleosts, 2010, Verlag Dr. Friedrich Pfeil, Munich, ISBN 978-3-89937-107-9 .