Schizoporella unicornis   (Johnston in Wood,  1844) (Bryozoan)
Organism information awaits expert curation
Class: Gymnolaemata

Image copyrights: René van Outryve & Hans De Blauwe

Size: Mature colonies range from 1-4 cm in diameter.

Color: Ranging in color from a whitish-pink to reddish-orange or brown.

Schizoporella unicornis is an encrusting bryozoan. Zooids broad, rectangular or polygonal, separated by distinct grooves, in altering series, occasionally in adjacent linear rows. Convex frontal with numerous perforations of evenly-spaced round pores. A prominent ridged umbo placed immediately proximal to the sinus. The sinus is shallow, U-shaped, between blunt, lateral condyles. Avicularia paired or single, lateral to the orifice, aligned with the sinus; rostrum acute triangular, directed disto-laterally. Polypide with 20-21 tentacles. Ovicell prominent, globular, frontal surface smooth or with a small umbo, lateral and distal surfaces perforated by small pores and bearing radiating ridges, particularly pronounced round the base where they impart a fluted appearance.

Schizoporella unicornis is a long-lived species that broods its young in a special chamber: the ovicell. In some specimens, more than one ovicell is present, however only one embryo is brooded at a time. Schizoporella unicornis is a hermaphrodite, with eggs being retained and fertilized in the ovicell, and sperm being shed to the water column, where they are caught in the feeding currents of other zooids. Brooded embryos are given nutrition via the ovicell, and once released, the non-feeding larvae are shortlived. Embryos orange-red. Ancestrula oval, glassy, with an unpunctured wall; its orifice semicircular, without a sinus, surrounded by eight spines; budding a distal triplet of zooids.

Synonym (s)
Lepralia unicornis (Johnston in Wood, 1844
Schizoporella unicornis Hincks, 1880
Lepralia unicornis (Johnston, 1874)
Schizoporella unicornis (Lagaaiji, 1952)

Common Name (s)
• Single Horn Bryozoan (English)
• Orange Encrusting Bryozoan (English)
Economic Importance and Threats
Importance:  Dangers
(Schizoporella unicornis is an abundant fouling organism capable of encrusting on a wide variety of substrata. This fouling can be a nuisance to shipping and ports, and has potential to be a problem to industrial components, cooling vents, etc. as in the case with other bryozoans. Single horn bryozoans exclude or inhibit the settlement and growth of native species, thereby modifying natural communities. Their stolons are extensions that develop at colonial interfaces and have been demonstrated to redirect or reverse the growth of competitors.)

Habitat:  Estuarine, Coastal
Trophic Level:  Consumer
Prey:  Phytoplankton, algae, bacteria or non-living organic particles
Predator:  Juvenile nudibranchs, flatworms and fish


• Kerala, Kochi, Willingdon Island INDIA
• Maharashtra, Mumbai (Lat: 18.9) (Long: 72.66) INDIA

Literature Source(s)
  • Balaji, M; Rao, MV and Rao, KS (1999) Natural resistance of ten species of catamaran grade timber to marine wood borer attack at Visakhapatnam and Kochi harbours Journal of the Marine Biological Association of India The Marine Biological Association of India, Cochin 41(1&2) 96-102 Available at - NIO, Goa
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at -
  • Hewitt, CL; Martin, RB; Sliwa, C; McEnnulty, FR; Murphy, NE; Jones, T and Cooper, S (Eds.) (2002) Schizoporella unicornis species summary. National Introduced Marine Pest Information System (NIMPIS). Date of access: 9/22/2009 Web publication Available at -
  • Global invasive species database Available at -
  • Gaonkar, CA; Sawant, SS; Anil, AC; Krishnamurthy, V and Harkantra, SN (2010) Changes in the occurance of hard substratum fauna: A case study from Mumbai harbour, India Indian Journal of Marine Sciences National Institute of Science Communication and Information Resources, CSIR, New Delhi, India 39(1) 74-84 Available at -

Page last updated on:2011-01-27

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