Anomalocarids + Trilobites- Prehistoric Giant Arthropods!

A reconstruction of anomalocaris canadensis.

Anomalocarids are an ancient marine arthropod relative. They are abnormal and resemble enlarged predatory shrimp, growing up to 1 m long. These giant hunters dominated the small tropical oceans where modern China is located today and ruled the Cambrian period. They are the earliest forms of an apex predator, feeding on every organism in the prehistoric seas, such as trilobites; hard-bodied invertebrates, and priapulid worms; which are soft-bodied invertebrates. Anomalocarids have enormous front appendages lined with serrated barbs for seizing unfortunate prey. These shrimp-like creatures may have flipped the hard-bodied trilobites over to expose the much softer underside. Cambrian marine life was bizarre, creatures such as hallucigenia crawled across the ocean floor like spiked, long-legged caterpillars!

A trilobite fossil.

Examples of larger organisms thriving in the cambrian seas are trilobites. Trilobites were a very successful group, they survived multiple mass extinctions and diversified each time. Unfortunately, they became extinct prior to the Triassic period, and thus never co-existed with dinosaurs and remain extinct today. However, during their time they were the first adapting form of life in existence. For example, multiple species developed large protruding spines, likely present to offend possible predators. Others became more stream-lined and formed large compound eyes, these species would have actively swam through open seas. On the other hand, most early species were flat and lacked large eyes – adapted to consuming organic matter and even burying beneath thin layers of rock and sand.

Giant Burrowing Cockroach – Largest Cockroach Alive!

ARTHROPOD OF THE WEEK IS…

A pinned specimen, picture taken by Mark Pellegrini (Raul654).

The Giant Burrowing Cockroach (Macropanesthia rhinoceros) is the largest extant cockroach, though it doesn’t compare to prehistoric cockroaches, it grows to 8 cm in length and weighs 35 g – almost the same weight as a hamster. Despite what you may think about the common pest, the American cockroach (Periplaneta americana), out of 4,500 species, only 30 are pests! The Giant Burrowing Cockroach is highly beneficial to the environment which it lives in, and are adapted to burrowing with their heavily hooked tarsi to shift substrate and consume decomposing plant matter. They are native to Australia and may bury down to approximately 1 metre underground. This species, in the pet trade, are often kept – their environment is easy to replicate and they will breed and reach maturity without complications.

Insect Life on Mars?

Photo taken by NASA Mars Rover

Is it possible that arthropods have inhabited Mars? Recently, Ohio scientist, William Romoser, has compiled photographs, taken from NASA’s Mars Rover which he believes to be living reptile-like insects. Described on this diagram to the left, this entomologist has labelled the primary features. The abdomen, thorax, compound eye, legs and head. The insect resembles some species belonging to Coleoptera, beetles such as a darkling beetle (tenebrionidae). He also shows, in other diagrams, the presence of a spiracle on the left side of the body. However, there isn’t enough proof to conclude these photos depict extra-terrestrial lifeforms. Some believe they are simply rocks shaped like familiar insects.

He states that there has been and is still life on Mars. Romoser tells us that some of the photographs seem to portray fossilized invertebrates also. Right now, no-one can be sure that these are Martian fauna, it is until expert taxonomists are able to physically interact with these potential aliens that we will be able to recognise these organisms as live animals.

Welcome to Sam’s Inverts!

Hi! Welcome to Sam’s Invertebrates, here you can find information about different invertebrates. There are care guides to provide you information about keeping these fascinating animals as pets as well as frequent posts to inform you about the latest discoveries in the insect universe. We cover mantises, beetles, arachnids and more! Enjoy!

You can find care sheets here:

Giant Asian Mantis | Ghost Mantis | Western Tailless Whip | Zebra Spider | Peacock Mantis