Triturus carnifex (Laurenti, 1768)

Taxonomy and Naming

The Italian crested newt, with the scientific name Triturus carnifex, is a newt species belonging to the Salamandridae family.

Geographic Distribution

This species is distributed across parts of Italy and the Balkans.

Breeding Aquatic Duration

It breeds in aquatic environments and may stay in water for up to four months at a time.

Breeding Entry Timing Factors

The timing of when T. carnifex enters water for breeding depends on the location of its breeding ponds.

Swimming and Habitat Preference

As a nektonic species that swims freely independent of water currents, T. carnifex prefers deep water habitats.

Pond Selection Rationale

It tends to favor ponds over larger bodies of water, which may be explained by the absence of predatory fish in these ponds.

Northern European Pond Selection

They typically select ponds in northern Europe, where temperatures are colder.

Breeding Pond Arrival and Departure Timeline

Adult T. carnifex begin arriving at breeding ponds between February and May, and leave between July and October.

Warm Pond Migration Patterns

At warmer ponds, adult newts arrive within a month and leave during a two-week period in July.

Rainfall and Migration Correlation

Andreone and Giacoma (1989) speculated that newt migration into breeding ponds increases after rainy days, because rainfall removes humidity-related limitations on newt activity.

Altitude and Body Size Relationship

Higher altitudes with colder temperatures directly affect the body size of T. carnifex.

Temperature Impact on Body Size

Ficetola et al. (2010) found that living in colder temperatures causes increased body size in both male and female T. carnifex.

High Altitude Female Reproductive Advantage

Females at higher altitudes are larger, which occurs because they carry more oocytes and have larger ovaries, giving them a reproductive advantage over smaller females.

Thermoregulation and Body Size

T. carnifex is poikilothermic, and a larger body size helps reduce heat fluctuations.

Body Size and Temperature Fluctuation Correlation

Ficetola also found that T. carnifex body temperature fluctuations decrease as body size increases.

Resource-Related Body Size Increase

Increased body size is also seen in areas with higher precipitation or nearby primary producers, as these conditions provide increased resources for the animals.

Human-Induced Habitat Alteration

Human activity has dramatically altered T. carnifex habitat through the expansion of industrial areas and urban centers.

Landscape Fragmentation Impacts

This causes fragmentation of natural landscapes, leading to selective extinction, genetic drift, and inbreeding caused by population isolation.

Fish Introduction Threat

The introduction of fish to isolated wetland habitats also contributes to amphibian population decline, as fish prey on newt larvae.

Niche Partitioning with Co-Occurring Newts

To avoid competition with other co-occurring newt species, T. carnifex generally reproduces in the deeper sections of ponds and is more nocturnal.

Interspecific Predation

Thanks to its larger body size, T. carnifex can prey on smaller newt species such as the palmate newt.

Reproductive Female Thermoregulation

Reproductive female T. carnifex have been shown to regulate their body temperature more precisely, and prefer higher temperatures, than non-reproductive females and males.