Santa Cruz Island
Two thirds of the invertebrates in Galapagos are insects (over 1,900 species). However, only very few of them are likely to be seen, and fewer identified by the casual visitor. Insects are one of the lesser-known groups of animals in Galapagos. Just as recently as the year 2000, the Charles Darwin Station officially inaugurated an invertebrate department. This department includes an entomology section. Our knowledge of the insect fauna has increased enormously in the last two years and will continue growing in the years to come, new additions being released continuously and many still in press.
Today, while visiting the highlands of Santa Cruz, some of our guests and I were lucky enough to find one of the most spectacular insects that inhabit the archipelago. A specimen of the native giant long-horn beetle (Stenodontes molarius) was observed perfectly under a branch at medium height. Beetles are in the order Coleoptera, or hard winged insects, which contains by far the greatest number of insect species on Earth. So far nearly 300,000 species have been described, which corresponds to over two-fifths of all the insects that have been named. Up to this date, 411 beetle species from 238 genera and 59 families have been registered in the Galapagos Archipelago (Peck 1996). 67% of the beetle species found here are endemic, 24% native and 9% introduced. The establishment of the 335 native and endemic species is believed to be the result of just 257 successful colonization events (Peck and Peck 1990). Although this number may sound large, when averaged over three million years it would represent just one successful establishment every 11,700 years! I was sincerely very excited, as I was able to take a picture of this rarely seen species for the very first time. This giant insect is the largest beetle species found on the islands, growing to some 6 cm (2 to 3 inches) in length. They are equipped with a powerful pair of pincers. The pincers are larger in the male than the female and are used in both sexes for digging into trees and plants. In the males these pincers are used in fighting other males for the females. Eggs are laid in dead wood and when hatched, larvae bore long tunnels in the rotten wood that serve both as refuge and food. The adults feed on plant sap, nectar and pollen.
A very interesting piece of data is that the grubs of these beetles are an important food source for the endemic woodpecker finch.
Two thirds of the invertebrates in Galapagos are insects (over 1,900 species). However, only very few of them are likely to be seen, and fewer identified by the casual visitor. Insects are one of the lesser-known groups of animals in Galapagos. Just as recently as the year 2000, the Charles Darwin Station officially inaugurated an invertebrate department. This department includes an entomology section. Our knowledge of the insect fauna has increased enormously in the last two years and will continue growing in the years to come, new additions being released continuously and many still in press.
Today, while visiting the highlands of Santa Cruz, some of our guests and I were lucky enough to find one of the most spectacular insects that inhabit the archipelago. A specimen of the native giant long-horn beetle (Stenodontes molarius) was observed perfectly under a branch at medium height. Beetles are in the order Coleoptera, or hard winged insects, which contains by far the greatest number of insect species on Earth. So far nearly 300,000 species have been described, which corresponds to over two-fifths of all the insects that have been named. Up to this date, 411 beetle species from 238 genera and 59 families have been registered in the Galapagos Archipelago (Peck 1996). 67% of the beetle species found here are endemic, 24% native and 9% introduced. The establishment of the 335 native and endemic species is believed to be the result of just 257 successful colonization events (Peck and Peck 1990). Although this number may sound large, when averaged over three million years it would represent just one successful establishment every 11,700 years! I was sincerely very excited, as I was able to take a picture of this rarely seen species for the very first time. This giant insect is the largest beetle species found on the islands, growing to some 6 cm (2 to 3 inches) in length. They are equipped with a powerful pair of pincers. The pincers are larger in the male than the female and are used in both sexes for digging into trees and plants. In the males these pincers are used in fighting other males for the females. Eggs are laid in dead wood and when hatched, larvae bore long tunnels in the rotten wood that serve both as refuge and food. The adults feed on plant sap, nectar and pollen.
A very interesting piece of data is that the grubs of these beetles are an important food source for the endemic woodpecker finch.
