Molluscs › Pen Shells
Stiff Pen Shell
Atrina rigida
25 photos
Study shows up to four per card, from different observers, so you learn the species rather than one picture. Heart the good ones and swap any you do not like.
Photos you add are credited to you, and you keep the copyright.
Easily confused with
Sawtooth Pen ShellAtrina serrata
Half-naked Pen ShellAtrina seminuda
Pinna rugosa
Atrina tuberculosa
Amber Pen ShellPinna carnea
Atrina maura
Encrusting fan-leaf algaLobophora variegata
ConchfishAstrapogon stellatus
Study checks a spoken answer against these, and tells you which one you named.
Where it is recorded
| United States | 1,183 |
|---|---|
| South Carolina | 54 |
| Texas | 41 |
| North Carolina | 34 |
| Mexico | 27 |
| Yucatan | 23 |
| Georgia | 14 |
| Alabama | 4 |
| Campeche | 2 |
| New Jersey | 1 |
Counts show where people looked, not only where it lives.
Traits
Physical
- Shell-bearingProtected by a hard shellFrom its classification
Group and habits
- Filter feederFeeds by filtering suspended food particles from water.From its classification
Classification
| Kingdom | Animals · Animalia |
|---|---|
| Phylum | Molluscs · Mollusca |
| Class | Bivalves · Bivalvia |
| Order | Oysters and Allies · Ostreida |
| Family | Pen Shells · Pinnidae |
| Genus | Atrina |
Sources
- Names, taxonomy and observation counts: www.inaturalist.org
- Photos and recordings: the creator and source are on each one.
- How much to rely on each source
Remember the name next time.
Practise Stiff Pen Shell with real photos from different observers. Say the name out loud, and it comes back just before you would forget it.