A CALIFORNIA TARANTULA
This is the fifth and final part of my series on animals that live (or once lived) in the vicinity of the Placerita Canyon Natural Center, just west of Newhall, Southern California.
Tarantulas comprise a group of large and often hairy spiders. There are about 1,100 described species. They emerged about 120 million years ago [= middle Early Cretaceous time]. It seems that they initially spread from Africa into India. Subsequently, they spread to all the other continents except Antarctica.
Tarantulas are different from spiders as tarantulas look down, whereas true spiders face each other. Also, tarantulas have two lungs, as opposed to true spiders (which have only one lung).
Tarantulas live in burrows and are nocturnal animals that feed at night. They mainly eat insects (grasshoppers, beetles, small spiders, etc.). Also, taranutlas are canabalistic, therefore, they do not live in colonies.
Classification
Kingdom Animalia
Phylum Arthropoda
Class Arachnida
Order Araneae
Family Theraphosidae
Genus Aphonopelma [a genus native to the Americas]
Species eutylenum [the “California Ebony” Tarantula]
Despite their fearsome appearance, these tarantulas are not harmful to humans. Genus Aphonopelma, whose taxonomy is poorly understood, is comprised of about 90 known species, many of which are hard to identify.
Aphonopelma eutylenum is a burrowing species that lives in a semi-arid climate.
REFERENCES (for the tarantula part of this blog post).
Hogue, C.L. (revised and edited by J.N. Hogue). 2015. Insects of the Los Angeles Basin, 3rd ed. Natural History Museum of Los Angeles County. 474 pp.
Wikipedia, 2025.
"SOME WORMS"
Millipedes
The Latin word mille refers to “thousand,” and the word ped refers to “foot.”
Millipedes have two pairs of legs on most of their body segments.
Millipedes are slow-moving, and they eat mostly decayed plant matter. Some eat fungi or drink plant fluid.
Classification
Kingdom Animalia
Phylum Arthropoda
Class Diplopoda
Order (16 of them!)
The fossil record of millipeds is the Silurian Period (about 430 million years ago) to present day.
Millipedes have body length of 1/16 to 14 inches long. There are two pairs of legs on most of their body segments. These animals are mainly burrowers and primarily detritovores although a few are herbivores, and even fewer are carnivores. They have no venom. They have single pair of antennae.
The study of millipedes is known as diplopodology (a good word for the game of Srabble).
Centipides
The Latin word centi refers to “hundreds.” They have 1 pair of legs per body segment. These animals are mainly burrowers and primarily carnivores. Their front legs bear venomous fangs! Do not pick up these animals. All centipides are venomous!
Classification
Kingdom Animalia
Phylum Arthropoda
Class Chilopoda
Order (2 of them)
The fossil record of centipedes extends from Late Silurian time (about 430 million years ago) to present day. Centipedes have only a single pair of legs per body segment. antennae. These animals are generalist predators, hence they eat a large variety of prey.
Note: Millipedes and centipedes have more than six legs, thus they are not insects.
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EARTHWORMS
Kingdom Animalia
Phylum Annelida
Clades 2 of them
Class Clitellata
Order Opisthopora
Suborder Lumbricina
Earthworms live in moist, compost-rich soil. They east living microoorganisms (e.g., funig, bacteria, detritus, etc.). The earthworm’s digestive system runs the length of its body = a segmented tube.
Earthworms lack a skeleton but have a nervous system. Muscles allow the worm to move.
An earthworm is both male and female.
Suprisingly, earthworms have a fossil record that literally traces back to about 1 billion years ago because these fossils are represented as burrow traces of tubular organisms. In Cambrian time, there are impressions of earthworms (genus Dannychaeta) that had guts, heads, etc. The earthworm (general concept) has a fossil record that extends back to the Cambrian Period approximately 500 million years ago. True earthworms appeared about 209 million years ago when the Pangaea supercontinent “broke apart.”
Reference
Wikipedia, 2026