Amphibians
Stripeless Tree Frog
Hyla meridionalis · also called Mediterranean tree frog
A bright green frog clings to a leaf in a Mediterranean garden, and the single detail that tells an observer exactly which of two very similar tree frog species they are looking at is not a marking that is present, but one that simply is not there at all.
Overview
The stripeless tree frog, Hyla meridionalis, is a bright green amphibian native to forest and wetland-edge habitat across the western Mediterranean, including Spain, southern France, and northwestern Africa. Its telling absence of the lateral stripe carried by close relatives, somewhat larger size, and loud breeding-season chorus make it a familiar and distinctive presence across its range.
Identified by what it lacks
While most identification features are things to look for, the stripeless tree frog is most reliably told apart from its closest relative by a feature that simply is not there, an absent stripe that turns a negative observation into the clearest field mark available.
Status
Least Concern overall and widespread across the western Mediterranean, though localised declines have occurred where breeding ponds are drained, polluted, or affected by drought.
Stripeless Tree Frog: common questions
Why is it called the stripeless tree frog?
This species lacks the continuous dark lateral stripe that most other European tree frogs, including the closely related European tree frog, display running along the side of the body, and this simple absence of a marking that is otherwise a defining feature of the group gives the species its common name and serves as its most reliable identification feature in the field.
How is the stripeless tree frog different from the European tree frog?
Beyond lacking the lateral stripe, this species is somewhat larger on average than the European tree frog, and where the two species' ranges overlap in parts of the western Mediterranean, the presence or absence of that stripe generally remains the clearest and most reliable way to distinguish between them without needing a closer physical examination.
Where does the stripeless tree frog live?
This species is native to forest and wetland-edge habitat across the western Mediterranean, including parts of Spain, southern France, and northwestern Africa, generally found in vegetation near breeding ponds and other suitable water during the breeding season and higher up in trees and shrubs at other times of year.
Why has the stripeless tree frog declined in parts of its range?
While the species remains widespread and is assessed as Least Concern overall, localised declines have occurred where breeding ponds have been drained, polluted, or increasingly affected by drought conditions, since this species, like most amphibians, depends on reliable access to suitable standing water for successful breeding each year.