Abstract
Sea chubs, family Kyphosidae, have a global distribution and are consumers of macroalgae in some temperate and all tropical reef systems. We
determined phylogenetic relationships of the ingroup and related outgroup taxa using partial fragments from mitochondrial markers (12s, 16s,
cytb, tRNA -Pro, -Phe, -Thr and -Val) and three nuclear markers (rag1, rag2, tmo4c4), in total comprising 5960 bp from 118 individuals. The
basal taxa in the kyphosid topology, Neoscorpis lithophilus (eastern South Africa to southern Mozambique), Kyphosus cornelii (Western
Australia) and Hermosilla azurea (southern California to Baja), are all herbivorous, and have a subtropical to temperate distribution. This,
together with a sister-group relationship to the temperate, omnivorous scorpidids, implies that the common ancestor of kyphosids was
herbivorous or omnivorous, and inhabited the subtropical Indo-Pacific. A chronogram using several outgroup fossil calibrations revealed that
kyphosids originated in the sub-tropical Indo-Pacific during the late Eocene or early Oligocene, and rapidly colonized subtropical seas.
Kyphosus originated relatively recently, in the early Miocene. The temperate clade of Kyphosus, represented by the Australasian K. sydneyanus
and K. gladius, diverged from the common ancestor of the tropical kyphosids between the late Miocene and the early Pliocene. The tropical
kyphosids diversified on low latitude reefs much more recently in the Pliocene and Pleistocene, when they speciated rapidly and evolved new
dietary preferences. Diversification into low latitude reef systems was geographically comprehensive and occurred during a period of marked
environmental fluctuation in tropical oceans. Herbivory is a basal trait and originated in temperate environments, while zooplanktivory in the
tropical, autapomorphic Sectator ocyurus is derived.
determined phylogenetic relationships of the ingroup and related outgroup taxa using partial fragments from mitochondrial markers (12s, 16s,
cytb, tRNA -Pro, -Phe, -Thr and -Val) and three nuclear markers (rag1, rag2, tmo4c4), in total comprising 5960 bp from 118 individuals. The
basal taxa in the kyphosid topology, Neoscorpis lithophilus (eastern South Africa to southern Mozambique), Kyphosus cornelii (Western
Australia) and Hermosilla azurea (southern California to Baja), are all herbivorous, and have a subtropical to temperate distribution. This,
together with a sister-group relationship to the temperate, omnivorous scorpidids, implies that the common ancestor of kyphosids was
herbivorous or omnivorous, and inhabited the subtropical Indo-Pacific. A chronogram using several outgroup fossil calibrations revealed that
kyphosids originated in the sub-tropical Indo-Pacific during the late Eocene or early Oligocene, and rapidly colonized subtropical seas.
Kyphosus originated relatively recently, in the early Miocene. The temperate clade of Kyphosus, represented by the Australasian K. sydneyanus
and K. gladius, diverged from the common ancestor of the tropical kyphosids between the late Miocene and the early Pliocene. The tropical
kyphosids diversified on low latitude reefs much more recently in the Pliocene and Pleistocene, when they speciated rapidly and evolved new
dietary preferences. Diversification into low latitude reef systems was geographically comprehensive and occurred during a period of marked
environmental fluctuation in tropical oceans. Herbivory is a basal trait and originated in temperate environments, while zooplanktivory in the
tropical, autapomorphic Sectator ocyurus is derived.
| Translated title of the contribution | Oprindelse af herbivori blandt rorfisk (F Kyphosidae) og tætbeslægtede taxa |
|---|---|
| Original language | English |
| Publication date | Jul 2013 |
| Number of pages | 1 |
| Publication status | Published - Jul 2013 |
Keywords
- Faculty of Science