User:Erinsk530/Katharina tunicata



Katharina tunicata (Wood, 1815) is commonly known as the Black Katy chiton, Black Leather chiton, Black chiton, or Leather chiton. Capable of growing up to 12cm, it's generally described as being football shaped with a black leathery girdle that embeds protective plates shaped like diamonds. Their underside is dull orange or yellow.

Systematics
Phylum: Mollusca

Class: Polyplacophora

Order: Neoloricata

Suborder: Ischnochitonina

Family: Mopaliidae

Genus: Katharina

species: K. tunicata

Anatomy
From the dorsal view, the mantle, girdle, and 8 valves are easily distinguishable. The girdle is covered with a chitinous cuticle. The ventral side shows the muscular foot surrounded by the gills on either side. This view also shows the mouth, anterior to the foot, and the anus, posterior to the foot encompassed by the mantle cavity and pallial fold which is then surrounded by the girdle. The gonopores are located at the posterior end just above the anus. The nervous system consists of four nerve cords, two assigned to the foot and two are visceral.

Habitat
Found in intertidal zones to 40m depths. Heavy waves on rocky shores are favorable. K. tunicata is unique compared to other chitons in that it tolerates direct sunlight. It's distribution ranges from Kamchatka, Russia through the Aleutian Islands to southern California

This species is protected under the Coastal Zone Management Act. These intertidal zones are susceptible to contamination from industrial activities, timber harvesting, mining, seafood processing, as well as coastal development. Over-visitation and over-harvesting are a common concern. Effects of climate change, present and future, are not fully understood but it will likely affect the diversity and structure of the intertidal communities K. tunicata reside in.

Feeding Habits
Like other chitons, it's a slow moving grazer that consumes several species of brown and red algae including kelps, sea lettuce, and encrusting diatoms. They're also known to eat sponges, tiny barnacles, spirobid polychaetes, and bryozoans. They're predators include sea urchins, leather stars, black oystercatchers, glaucous-winged gulls, and humans.