Chthamalidae

Classification

Phylum: Arthropoda
Subphylum: Crustacea
Class: Maxillopoda
Subclass: Thecostraca
Order: Sessilia
Family: Chthamalidae

Pronunciation

How to pronounce Chthamalidae: //kθəˈmælɪdiː//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Chthamalus dalli - Allison Gong by Allison Gong. Used under a CC BY 4.0 license.

Summary

Chthamalidae are a family of chthamaloid barnacles characterized by a distinctive shell structure and their preference for intertidal habitats, comprising at least 56 recognized species.

Physical Characteristics

The shell wall consists of eight wall plates that may reduce to six or four in some species. The rostrum rarely fuses with the rostrolatus. They have a membraneous or rarely calcareous basis, and generally lack imbricating plate whorls. Soft parts have rare caudal appendages, and the mandible usually has three to four teeth. Specialized comb and card setae are present on filter-feeding cirri.

Identification Tips

The easiest characteristic for field identification is the absence of whorls of imbricating basal plates, which distinguishes them from the Catophragmidae family.

Habitat

They live in intertidal to subtidal habitats, often in rigorous wave-washed locations and some species are found in the surf zone above the high tide mark.

Distribution

Chthamalidae are found in all oceans except the Arctic Ocean, particularly in temperate and tropical zones.

Diet

They feed by filtering food particles from the water, utilizing specialized setae on their cirri.

Ecosystem Role

As filter feeders, they play a vital role in the marine ecosystem by contributing to the nutrient cycle and providing food for various marine species.

Evolution

Taxonomic classification is challenging due to convergence in shell and opercular form, with characters weighted to soft part morphology.

Similar Taxa

Catophragmidae
Coronuloidea
Balanoidea

Misconceptions

Some may conflate Chthamalidae with similar barnacle families due to morphological similarities; it is important to note the lack of imbricating plate whorls in Chthamalidae.