The scientific name for a spider depends on whether one is referring to the entire group or a single species. Common names, such as “house spider” or “tarantula,” vary widely across regions, making them unreliable for scientific discussion. Scientists require a universal system to ensure precise identification of the approximately 50,000 known species of spiders globally. This formal classification provides clarity and stability for research.
Understanding Binomial Nomenclature
The foundation for this global system is binomial nomenclature, a standardized naming convention that provides a unique identifier for every species. This “two-term naming system” assigns every species a two-part scientific name. The names are based on Latin or Latinized words, ensuring stability because Latin is a non-changing language.
The two parts of the scientific name are the genus, which is capitalized, and the species, which is written in lowercase. For example, a house cat is named Felis catus, where Felis is the genus and catus is the species. This two-word designation serves to distinguish one species from all others within the same genus.
The Scientific Name for All Spiders (Order Araneae)
To find the scientific name for the entire group of spiders, one must look higher in the classification hierarchy than genus and species. Spiders belong to the Class Arachnida, a large group that also includes scorpions, mites, and ticks. Since not all arachnids are spiders, the term “Arachnida” is too broad to be the specific scientific name for the group.
The most specific collective scientific name for true spiders is the Order Araneae. This name functions as the formal, universal classification for the entire biological group. The order is defined by a unique set of physical characteristics that distinguish spiders from other arachnids.
Spiders within the Order Araneae possess a body divided into two main sections, the cephalothorax (or prosoma) and the abdomen (or opisthosoma), which are connected by a small stalk called the pedicel. They have eight legs attached to the cephalothorax and fangs, known as chelicerae, that are generally capable of injecting venom. A defining feature of all members of the Order Araneae is the presence of spinnerets, specialized abdominal appendages that extrude silk from various silk-producing glands.
How Specific Spiders Get Their Names (Genus and Species)
While Araneae is the collective name for all spiders, the scientific name for an individual kind of spider follows the two-part binomial nomenclature system. This name is always italicized and contains the genus followed by the species name. For instance, the southern black widow spider is formally known as Latrodectus mactans.
In this example, Latrodectus is the genus that groups together all widow spiders, while mactans is the specific epithet that identifies this particular species. Similarly, the common house spider is scientifically named Parasteatoda tepidariorum. The genus Parasteatoda belongs to the Family Theridiidae, which is the family of tangle-web or cobweb spiders, also including the black widows.
This system allows for precise organization, as scientists can also group related genera into a Family, like Theridiidae, to show a closer evolutionary relationship. For example, the tarantulas, which include many individual species with their own binomial names, are all grouped into the Family Theraphosidae.