Semelparous
Guides
Geolycosa
Burrowing Wolf Spiders
Geolycosa is a genus of burrowing wolf spiders (family Lycosidae) established by Montgomery in 1904. These spiders are characterized by their obligate burrowing lifestyle, constructing deep cylindrical burrows in sandy or loose soils. Some species build distinctive turrets around burrow openings using sticks and debris. The genus includes approximately 70 species distributed across North America, with some species extending into the Levant. Geolycosa species are medium to large spiders with morphological adaptations for digging, including enlarged chelicerae and stout anterior legs.
Ligia oceanica
sea slater, common sea slater, sea roach
Ligia oceanica is a large intertidal isopod reaching up to 35 mm in length, making it the largest species in the suborder Oniscidea. Native to rocky Atlantic coasts of Europe, it has been introduced to eastern North America and Atlantic islands. This semelparous species inhabits the supralittoral zone, hiding in rock crevices by day and emerging nocturnally to feed. Molecular phylogenetics suggests closer affinity to marine isopod suborders Valvifera and Sphaeromatidea than to terrestrial woodlice, challenging traditional classification.
Squilla
mantis shrimp, spearer mantis shrimp
Squilla is a genus of stomatopod crustaceans commonly known as mantis shrimp or spearer mantis shrimp. Members of this genus are small marine predators, typically 40–70 mm in length, characterized by raptorial appendages adapted for spearing soft-bodied prey rather than smashing hard shells. The genus has a fossil record dating to 145 million years ago and has diversified into over a dozen extant species. Squilla species are distributed in tropical and subtropical marine waters worldwide, including the Indian Ocean and Mediterranean Sea.
Tylos punctatus
Spotted Calloused Beach Pillbug
Tylos punctatus is a large, strictly nocturnal sand-beach isopod inhabiting sheltered intertidal zones from southern California to Baja California. It exhibits remarkable behavioral adaptations to this harsh environment, including precise burrowing cycles synchronized with tidal patterns and seasonal dormancy. The species has an exceptionally slow life history for an isopod, with females breeding only once annually after reaching maturity at approximately three years of age.