Scientific:
Anguis fragilis (Linnaeus, 1758)
English: Slow Worm
Spanish: Lución
Portuguese: Licranço
Galician: Escáncer común
Family: Anguidae
Distribution: northern Spain and north and central Portugal, as well as the entire European mainland, excluding Ireland but including Scandinavia up to central Finland and eastwards as far as Turkey and Iran, the Caucasus and western Siberia.
The sole member of its genus, related to the much larger European legless lizard
Ophisaurus [Pseudopus] apodus as well as to other Old and New World legless lizards.
Anguis fragilis fragilis is the western subspecies found in Iberia. It is distinguished by having 24-26 scale rows at midbody and normally lacking blue spotting in the males.
A. f. colchicus is the eastern subspecies found in SE Europe and further south and east. It usually has 26-30 scales rows at midbody, and males and some females often have blue spotting.
This is the only truly legless lizard in Spain and Portugal. It can be distinguished from snakes by its eyelids and visible ear openings, features that all snakes lack, and from the amphisbaenian
Worm Lizard (Blanus cinereus) by its eyes, these being vestigial and almost invisible in the amphisbaenian. In addition scales on the amphisbaenian are very obviously arranged in rings around the body, which is not the case with the Slow Worm. The
Western Three-Toed Skink (Chalcides striatus) is somewhat similar but on closer inspection will show its small limbs. In coloration
A. fragilis is overall a uniform colour, usually brown, grey or bronze but sometimes red or copper, with the underneath a shade of grey. Males are fairly plain but females often have a vertebral stripe, dark sides and belly. The young are a striking gold or silver with a similar stripe and dark patterning to the female. In addition to normal coloration, both albino and melanistic (very dark or all black) individuals have been found. The scales are smooth. Apart from the variation in coloration there are no known differences among the Iberian populations.
Adult Slow Worms reach about 50 cm, of which more than half may be the tail if unregenerated (i.e. not broken off). However, regenerated tails are quite common in this species, as they frequently “break” and the regenerative process is very minimal. Another easy way to distinguish the Slow Worm at a glance from a snake is its rather awkward way of movement as opposed to the smooth, apparently effortless gliding of a snake.
The species is found in northern areas of Spain and Portugal including north Catalonia, Basque Country, Cantabria, Asturias, León, the Sistema Ibérico, Zamora, Salamanca, Galicia and the Pyrenees, where it can be found up to 2,400m. In fact in terms of habitat it is very adaptable, being found from sea level to mountain altitudes generally and also in a variety of environments including meadows, areas of undergrowth, railway and even motorway embankments. The common factor seems to be that the ideal environment is damp but not wet and not too sunny, possibly why this species is not found in the south of the Iberian Peninsula. Slow Worms are reclusive animals, so their habitat is often characterised by plentiful cover in the form of undergrowth, fallen leaves, stones, etc. They often hide beneath rocks or fallen wood, manmade items such as sheet iron or rubber mats also being utilised. The species is diurnal (daytime active), its maximum activity normally taking place 5-10am and 6-9pm in Spain and Portugal. It may also be encountered after a shower of rain, possibly because of the greater possibility of finding mollusc prey.
The Slow Worm preys mainly on gastropods (small slugs and snails), for which reason the species should be a welcome visitor to any garden. It will also take arthropods and sometimes small reptiles such as the Common Lizard (
Zootoca [Lacerta] vivipara) or the young of the Grass Snake (
Natrix natrix).
Breeding: in Iberia the Slow Worm emerges from hibernation in March. Courtship and mating take place in April to May, males fighting and wrestling each other. Mating itself may last up to 10 hours. A gravid female basks more and eventually gives birth after 11-13 weeks (i.e. in June to September) to 5-26 (average 6-12) young. In western Europe males breed at the age of 3-4 years, females at 4-5 years. Slow Worms enter hibernation in autumn, often forming communal dens of up to 100 individuals together with salamanders and (in a hibernation truce!) vipers in suitable frost-free places such as holes in the ground or among roots.
These seemingly slow and inoffensive reptiles are known for their longevity – 10-15 years in the wild is cited by one authority, another suggests 30 years, and there is a captive record for no less than 54 years.
The Slow Worm appears to be fairly abundant in its range and therefore less endangered by human activity than some other creatures. Unfortunately it is sometimes still mistaken for a snake and may be persecuted as a result. Across its range it has various predators including small carnivores, several birds of prey and snakes, including the Smooth Snake (
Coronella austriaca) and the Adder (
Vipera berus).
Scalation details are as follows: small rostral; 2-4 supranasals; rhomboid-shaped internasal; prefrontals may completely touch each other, or only partially or not at all; large frontal; occipital situated between parietals; 5-6 supraoculars; 4-5 submaxillaries on each side; average total of 10 supralabials. The loreal region has a number of small scales arranged in 3-4 rows.
Reptiles and Amphibians 
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