Species Report Percnon Gibbesi (Sally Lightfoot Crab)

Mediterranean invasive species factsheet www.iucn-medmis.org

Species report Percnon gibbesi (Sally lightfoot crab)

SCIENTIFIC NAME AND COMMON NAME REPORTS Percnon gibbesi 67

Key Identifying Features

This mimetic, relatively small crab is up to 3 cm across. Its body is flat and square-shaped with a smooth surface. The carapace is brownish green in colour, and the long, flattened legs are banded with golden yellow rings. The ventral surface is pale. The walking legs have a row of spines along the leading edge. The eyestalks and claws are orange; the claws are small in females and large and unequal in males.

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Other species that look similar

Identification and Habitat

It is found on rocky shorelines, in the crevices of rocks or on man-made structures such as ports and marinas at depths of 0.5–4 m.

Reproduction

Berried females have been recorded from May to September and juvenile crabs (carapace length = 1.5 cm) are present from October until March, suggesting the crab breeds during the summer months and recruitment takes place throughout the winter.

Similar Species

Percnon gibbesi may be distinguished from the native Mediterranean Pachygrapsus species by its deeply incised anterior shape, its colour pattern and its prominently spinose walking legs (particularly on the longest segment). Pachygrapsus marmoratus is mainly distinguished by the number of orbital teeth and its spoon-tipped claws; the colour of the species varies considerably and can be brown, purple, green or black. Pachygrapsus transversus is dark green to black in colour with a creamy ventral surface; it can be distinguished from P. marmoratus by having one tooth on each side of its carapace and 2–3 spines on the fifth walking leg.

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History and Route of Management Options Introduction Eradication may be impossible in practice as this It is native to the west and east coasts of species is too widespread in the Mediterranean America and the eastern Atlantic from Madeira Sea. Appropriate controls on vessel fouling to the Gulf of Guinea. In the Mediterranean, it (including on fishing and recreational vessels) was first recorded from Linosa Island, Italy, with and fishing nets may prevent further nearly simultaneous records from the Balearic introductions. Islands, Sardinia, off the Ionian coast of Calabria, the south-eastern Tyrrhenian Sea, Further Reading Sicily, Pantelleria Island and Malta. It then spread northward along the Tyrrhenian coast to Katsanevakis, S. et al. 2011.Twelve years after the Gulf of Naples and Giglio Island. In 2005, it the first report of the crab Percnon gibbesi (H. was recorded from Crete and Antikythira, Milne Edwards, 1853) in the Mediterranean: Greece, as well as the Mediterranean coast of current distribution and invasion rates. Journal Turkey. Since then, it has spread along both the of Biological Research-Thessaloniki 16: 224 – Ionian and the Aegean coasts. It is also known 236. from Tunisia, Libya and Egypt. It may spread in the ballast waters of ships and on fishing nets as http://www.europe-aliens.org/pdf/Percnon_gibbesi.pdf well as being transported in its larval stage by water currents.

Ecological Impacts

The sally lightfoot crab is a strictly herbivorous crab, consuming filamentous and calcareous algae. It is unclear whether it competes with other algivorous animals in its habitat, such as sea urchins, but exclusion of native crabs may occur in some areas. Its habitat overlaps with the native crab Pachygrapsus marmoratus, an omnivorous species that also feeds on filamentous algae, and the pebble crab Eriphia verrucosa, a carnivorous species that feeds on molluscs and polychaetes.

Economic Impacts

Unknown.

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Map of sightings of the species Percnon gibbesi (Sally lightfoot crab)

Legend

Algae Angiosperm Cnidarians Centre for Mediterranean Molluscs Crustaceans Ascidians Cooperation Combjellies / Fishes Ctenophores

More Information: Guide and reports platform for Marine Protected Areas (MPAs) in the Mediterranean. www.iucn-medmis.org

2013-2021 © IUCN Centre for Mediterranean Cooperation. More info: www.iucn-medmis.org Pag. 4/7 Mediterranean invasive species factsheet www.iucn-medmis.org

MPAs, Country Date Density Measure

Cabo de Gata Nijar, Spain Before 2013 -- --

Plemmirio, Italy Before 2013 -- --

Isole Pelagie, Italy Before 2013 -- --

Zakynthos, Greece Before 2013 -- --

Ses Salines y Freus d'Eivissa i Formentera, Before 2013 -- -- Spain

Serra de Tramuntana, Spain Before 2013 -- --

Karaburun-Sazani island, Albania Before 2013 -- --

El-Kouf, Libya Before 2013 -- --

Kas-Kekova, Turkey Before 2013 -- --

Cabo de Palos - Islas Hormigas, Spain Before 2013 -- --

Capo Carbonara, Italy Before 2013 -- --

Archipel de Kerkennah, Tunisia Before 2013 -- --

Illes Columbretes, Spain Before 2013 -- --

Isole di Ventotene e santo Stefano, Italy Before 2013 -- --

Costa degli Infreschi e della Masseta, Italy 01/09/2010 -- --

-- 10/04/2014 -- --

-- 02/07/2014 -- --

-- 27/07/2014 -- --

PN Calblanque, Spain 15/08/2014 -- --

Karaburun-Sazani island, Vlore,Albania 22/07/2015 -- --

-- 01/08/2015 -- --

Isole Tremiti, Italy 02/08/2015 -- --

-- 04/08/2015 -- --

-- 10/08/2015 -- --

Portofino, Italy 27/08/2015 -- --

Arcipelago Toscano, Italy 03/09/2015 -- --

-- 15/09/2015 -- --

-- 21/06/2016 -- --

-- 12/07/2016 -- --

-- 21/07/2016 -- --

Funded by: This collaborative effort is supported by: Mediterranean invasive species factsheet www.iucn-medmis.org

-- 31/07/2016 -- --

-- 05/08/2016 -- --

-- 09/08/2016 -- --

-- 10/08/2016 -- --

-- 12/08/2016 -- --

-- 18/08/2016 -- --

Cabo de Palos - Islas Hormigas, �guilas ,Spain 20/08/2016 -- --

-- 20/08/2016 -- --

Baie de Stagnolu, golfu di Sognu, golfe 21/08/2016 -- -- de Porto-Vecchio, France

-- 21/08/2016 -- --

-- 24/08/2016 -- --

-- 25/08/2016 -- --

-- 26/08/2016 -- --

-- 15/09/2016 -- --

-- 30/09/2016 -- --

-- 24/10/2016 -- --

-- 25/11/2016 -- --

-- 27/12/2016 -- --

-- 18/05/2017 -- --

-- 26/05/2017 -- --

-- 03/06/2017 -- --

-- 13/06/2017 -- --

-- 17/07/2017 -- --

-- 21/07/2017 -- --

-- 02/08/2017 -- --

Funded by: This collaborative effort is supported by: Mediterranean invasive species factsheet www.iucn-medmis.org

-- 03/08/2017 -- --

-- 06/08/2017 -- --

-- 20/08/2017 -- --

-- 23/08/2017 -- --

-- 22/10/2017 18.92 No. of individuals sighted

Cape Greco, Cyprus 25/04/2018 -- --

How to cite this tab: Percnon gibbesi - Invasive Alien Species Fact Sheet for Mediterranean Network of MPAs. From Online Database MedMIS (IUCN Center for Mediterranean Cooperation, Download date 26/09/2021.

More information about this species from: Otero, M., Cebrian, E., Francour, P., Galil, B., Savini, D. 2013. Monitoring Marine Invasive Species in Mediterranean Marine Protected Areas (MPAs): A strategy and practical guide for managers. Malaga, Spain: IUCN. 136 pages www.iucn.org/dbtw-wpd/edocs/2013-008-Es.pdf .

Funded by: This collaborative effort is supported by: