Spio

A Robust genera from the “Annelids” group, mostly found in Sand

Sand

Robust

Annelids

Genera Characteristics Recorded Traits Possible Values
Size in cm
  • 1-10 cm
  • <1 cm
  • 1-10 cm
  • 11-20 cm
  • >20 cm
Genera Characteristics Recorded Traits Possible Values
Motility (Adult)
  • Short Range Mobility
  • Adult
  • Short Range Mobility
  • Sedentary

“Short Range Mobility”

Motility (Larval)
  • Long Term Planktonic
  • Brooded or Laid Eggs
  • Long Term Planktonic
  • Short Term Planktonic
  • Brooded or Laid Eggs

“Long Term Planktonic” “Brooded or Laid Eggs”

Lifespan
  • 1-2 years
  • >10 years
  • 3-10 years
  • 1-2 years
  • <1 year
Maturity
  • <1 year
  • >4 years
  • 3-4 years
  • 1-2 years
  • <1 year
Fecundity
  • 100 - 1000
  • 1 - 10
  • 10 - 100
  • 100 - 1000
  • 1000 - 10000
  • 10000 - 1 million
  • > 1 million

Image: Spio © MES

Vulnerability

Spio is a small polychaete belonging to the Family Spionidae. It is usually 2-5cm in body length & lives in burrows in sand where it feeds as a surface deposit-feeder on detritus & diatoms. It has some mobility within the sediments, but is likely to be vulnerable to dredging & to the deposition of sediment mobilised by the dredging process.

 

Recoverability

Spio is a short-lived genus with a life-span of about 1yr. Sexual maturity is achieved at 2-3 months. The sexes are separate & approximately 250 eggs of 0.13-0.15mm are fertilised externally during two reproductive periods (April-June & August-September). The embryos are brooded in the tube & then released as lecithotrophic larvae that spend about 4 weeks in the plankton. Settlement is from June-August. The dispersal potential is high & the relatively short generation time & rapid growth rate suggests that restoration of the biomass is achieved soon after settlement. This genus has a high recoverability.

 

References

  • Biology

    • Giangrande, 1997
    • Hayward & Ryland, 1990
  • Taxonomy

    • Fauchald, 1977
    • Fauchald, 1977
    • Hayward & Ryland, 1995b
    • Howson & Picton, 1997
  • Distribution

    • Giangrande, 1997
    • Hayward & Ryland, 1995b
    • JNCC, 1999
    • Picton & Costello, 1998
  • Reproduction

    • Diaz-Castaneda et al., 1989
    • Eckert, 2003
    • Giangrande, 1997
    • Gudmundsson, 1985
    • Srikrishnadhas & Ramamoorthi, 1981