Galician newspaper La Voz de Galicia said some passengers were constantly checking their seats and the aisle for fear other spiders had got onto the plane despite the fumigation before it touched down in Vigo around midnight on Friday.
Baggage handlers are said to have discovered the cages the animals were in had been damaged and 132 of them were roaming around the cargo hold when the jet touched down in the Azores archipelago capital Ponta Delgada on Sao Miguel Island.
The Iberia plane’s onward journey was delayed so it could be fumigated and the pilot treated with anti-inflammatory medicine.
After leaving Casablanca to return to Madrid on Tuesday, the plane the spider appeared on had touched down in cities including Brussels, Zurich and Toulouse.
Last November a plane was grounded for five days after more than 130 hamsters in the hold managed to escape their cages as maintenance workers tried to round up the power-eating rodents.
