Astropecten
Astropecten aranciacus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	Asteroidea
Order:	Paxillosida
Family:	Astropectinidae
Genus:	Astropecten Gray, 1840
Species
See text.

Astropecten is a genus of sea stars of the family Astropectinidae.^[1]

Identification

Description of arm’s section of starfish genus Astropecten.
1- papulas: they are soft and retractable appendages with respiratory functions 2- paxilla 3- superomarginal spines 4- superomarginal plates 5- scales and small spines covering the vertical face of superomarginal plates 6- ambulacral plates 7- adambulacral plates 8- inferomarginal plates 9- inferomarginal spines 10- pedicellaria: special pedicels with prehensile termination necessary to grab bodies and detritus 11- external adambulacral spines 12- median adambulacral spines 13- internal adambulacral spines 14- ambulacral pedicellaria

Ossicles of an Astropecten irregularis

Ossicles of an Astropecten jonstoni

Flat ossicles of an Astropecten platyacanthus

These sea stars are similar one to each other and it can be difficult to determine with certainty the species only from a photograph. To have a certain determination, in some cases, animals should be analyzed in the laboratory or using genetic testing, but often it isn’t possible. In order to determine the species, with a reasonable margin of error, it’s necessary to observe the appearance of the animal, in particular, based on some typical features described by principal authors that have analyzed over the years a large number of specimens in the laboratory. The main elements, to determine the various species from photo, are: the appearance of the dorsal marginal plates and spines, the size, the shape of disc and arms. For a good identification by sea photo it is important to take a complete picture of all the subject, a picture of the detail of the marginal plates and to measure as precisely as possible the diameter of the sea star. All this can be done without touching, turning it, or disturbing the animal. Starfishes have two sides: an upper side called “aboral side” (which is normally visible), and a bottom side called “oral side” (which rests on the seabed).

• 
  General look of an Astropecten
• 
  Cross-section of an arm. 1=papula and paxilla, 2=superomarginal plate, 3=inferomarginal plate, 4=ambulacral plates, 5=adambulacral plate
• 
  Ossicles of an Astropecten aranciacus
• 
  Armtip of an Astropecten aranciacus

Species

• 
  Astropecten aranciacus
• 
  Astropecten armatus
• 
  Astropecten articulatus
• 
  Astropecten bispinosus
• 
  Astropecten irregularis
• 
  Astropecten jonstoni
• 
  Astropecten platyacanthus
• 
  Astropecten polycanthus
• 
  Astropecten preissei
• 
  Astropecten spinulosus
• 
  Astropecten lorioli (extinct, from the Jurassic)

References

• (in English) Roberto Pillon (2009). Astropecten of the Mediterranean Sea
• (in French) Koehler, Réné. 1921. Faune de France. Echinodermes.
• (in Italian) Tortonese, Enrico. 1965. Fauna d'Italia. Echinodermata.
• (in Italian) Tortonese, Enrico. 1934. Annali del Museo civico di storia naturale Giacomo Doria (Volume 57).
• (in German) Emil Edler Von Marenzeller (1875). Revision adriatischer Seesterne.
• (in German) Ludwig, Hubert. 1897. Die Seesterne des Mittelmeeres. Zoologischen station zu Neapel.
• (in German) Ludwig Heinrich Philipp Döderlein. 1921. Die Asteriden der Siboga-Expedition.
• "Astropecten". Integrated Taxonomic Information System.

External links

• (in English) Downloadable WoRMS: Roberto Pillon (2009). Astropecten of the Mediterranean Sea
• (in Italian) Downloadable WoRMS: Roberto Pillon (2009). Orientarsi in un mare di stelle
• (in English) WoRMS
• Jaselli, Luca. “REDESCRIPTION AND FIRST ILLUSTRATION OF THE HOLOTYPE OF ASTROPECTEN MONTALIONIS (MENEGHINI, 1852) [PAXILLOSIDA: ASTROPECTINIDAE.” Atti della Societa Toscana di Scienze Naturali (2018)]