Column Barnacles

Chamaesipho columna

How To Recognise It 2

The small barnacles are found on rocks around the high to mid tide marks, usually packed together quite tightly and forming a honeycomb look. The plates come together forming a ridge, instead of more flat like the other barnacles.

Found on exposed rocks and on larger shells.

Can be confused with C.brunnea 2

C.brunnea is a northern species, unlikely to be found south of Cape Foulwind / Banks Peninsula. Also it occupies the spray zone, and does not occur below mean high tide.

C.columna is found throughout NZ, and lives in the upper half of the tidal zone.

Both species look very similar, but C.columna is narrower and the jigsaw shaped joint between the scuta and terga is less pronounced and not as central as in C.brunnea (IE. about 1/3 in brunnea and 1/4 in columna).

Another key difference is that when C.columna crowd together they merge throughout the length of the shells, whereas C.brunnea abut only at the bases of their shells.

Chamaesipho brunnea page

Sources and Credits

  1. (c) Lisa Bennett, some rights reserved (CC BY), https://inaturalist.nz/photos/2987935
  2. (c) tangatawhenua, some rights reserved (CC BY-SA)

More Info

iNat Map

Location Aupourian, Cookian, Forsterian, Kermadec Islands
Depth High Tide, Low Tide, Mid Tide