Schmidtea mediterranea

Schmidtea mediterranea Benazzi, Baguñà, Ballester & Del Papa, 1975

Languages: English

Overview

General Description

Schmidtea mediterranea Benazzi et al., 1975 is a freshwater planarian (order Tricladida, suborder Continenticola, phylum Platyhelminthes) that is mostly known to the scientific community for its capacity to regenerate and has become a model organism for the functional analysis of the genes involved in pattern formation.

Author(s): Eva M Lázaro; Abdul H Harrath; Giacinta A Stocchino; Maria Pala; Jaume Baguñà; Marta Riutort
Rights holder(s): Eva M Lázaro; Abdul H Harrath; Giacinta A Stocchino; Maria Pala; Jaume Baguñà; Marta Riutort

Ecology and Distribution

Distribution

It is present in coastal locations and islands in the western Mediterranean: Catalonia, Menorca, Mallorca, Corsica, Sardinia, Sicily and Tunisia. Their populations are scattered.

In Catalonia, and in the whole Spain, only two populations are known. One is located in the Montjuïc Mountain, within Barcelona city. Specimens from Girona are also known, but recent searches didn't succeed in finding them.

Author(s): Solà, Eduard
Rights holder(s): Solà, Eduard

Evolution

It has been suggested that the common ancestor of S. mediterranea and its sister species, S. polychroa, diverged around 43 mya. S. mediterranea appeared at some time between these 43 mya and 20-5 mya.

Author(s): Solà, Eduard
Rights holder(s): Solà, Eduard

Habitat

Despite its present distribution in the Mediterranean, S. mediterranea seems to be adapted to moderate summer temperatures. That leads to think that this species is probably trapped in the Mediterranean since this area had a more suitable climate.

Author(s): Solà, Eduard
Rights holder(s): Solà, Eduard

Reproductive Behaviour

Reproduction

There are either amphimictic and/or asexual fissiparous populations. In both types of reproduction most of the populations are diploids.

The individuals that reproduce by fission (either diploids and triploids) bear a heteromorphic translocation between first and third chromosomes. This translocation only affects one chromosome of each pair.

The asexual populations are only present in Catalonia, Mallorca and Menorca. There is no sexual population known in this locations. The Menorca asexual population is triploid, while Catalonia and Mallorca populations are exclusively diploids.

Most of sexual populations are diploids with an exception, one in Sardinia is triploid.

Author(s): Solà, Eduard
Rights holder(s): Solà, Eduard

Conservation

Conservation Status

Schmidtea mediterranea populations are scattered and in some of the localities a population decline has been observed. This is the case of the asexual populations of Montjuïc (Barcelona) where it has apparently disappeared from two ponds after human intervention. In another pond of Montjuïc (Viver dels Tres Pins) the introduction of Schmidtea polychroa in 2007 seems to have had a deleterous effect on S. mediterranea population. The fourth pond with this species, “Pantà de la Fuxarda”, has been invaded by the crayfish Procambarus clarkii (Girard, 1852). Its introduction could menace S. mediterranea because its known to be able to change native plants and animal communities.

Author(s): Solà, Eduard
Rights holder(s): Solà, Eduard

Relevance

Uses

Schmidtea mediterranea is used in developmental and regeneration studies.

Author(s): Solà, Eduard
Rights holder(s): Solà, Eduard

Taxonomy

  • Dugesia mediterranea Benazzi, Baguñà, Ballester & Del Papa, 1975 (basionym)

References

Abril, J., Cebria F., Rodriguez-Esteban G., Horn T., Fraguas S., Calvo B., et al. (2010).  Smed454 dataset: unravelling the transcriptome of Schmidtea mediterranea. BMC Genomics. 11, 731. Abstract
Alvarado, A S. (2012).  Q&A: What is regeneration, and why look to planarians for answers?. BMC Biology. 10,
Benazzi, M., Baguñà J., Ballester R., Puccinelli I., & Papa R. D. (1975).  Further Contribution to the Taxonomy of the « Dugesia Lugubris-Polychroa Group » with Description of Dugesia Mediterranea N.SP. (Tricladida, Paludicola). Bolletino di zoologia. 42(1), 81-89.
Chong, T., Stary J. M., Wang Y., & Newmark P. A. (2011).  Molecular markers to characterize the hermaphroditic reproductive system of the planarian Schmidtea mediterranea. BMC Developmental Biology. 11, 69. Abstract
de Vries, E. J. (1985).  The biogeography of the genus Dugesia (Turbellaria, Tricladida, Paludicola) in the Mediterranean region. Journal of Biogeography. 12, 509-518.
Harrath, A. H., Alwasel S., Zghal F., & Tekaya S. (2012).  Ultrastructure of spermatogenesis and mature spermatozoon of the freshwater planarian Schmidtea mediterranea (Platyhelminthes, Paludicola). Comptes rendus biologies. 335, 87-95.
Lázaro, E. M., Harrath A H., Stocchino G., Pala M., Baguñà J., & Riutort M. (2011).  Schmidtea mediterranea phylogeography: an old species surviving on a few Mediterranean islands?. BMC Evolutionary Biology. 11,
Newmark, P. A., & Alvarado A S. (2002).  Not your father's planarian: a classic model enters the era of functional genomics. 3(3), 210 - 219.
Stocchino, G A., Sluys R., & Manconi R. (2012).  A new species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from the Afromontane forest in South Africa, with an overview of freshwater planarians from the African continent. Zootaxa. 3551, 43–58.
Vila-Farré, M., Sluys R., Almagro ío, Handberg-Thorsager M., & Romero R. (2011).  Freshwater planarians (Platyhelminthes, Tricladida) from the Iberian Peninsula and Greece: diversity and notes on ecology. Zootaxa. 2779, 1-38.
Wagner, D. E., Wang I. E., & Reddien P. W. (2011).  Clonogenic neoblasts are pluripotent adult stem cells that underlie planarian regeneration. Science. 332, 811-6. Abstract