Triturus pygmaeus lusitanicus, Arntzen, 2024

Arntzen, Jan W., 2024, Morphological and genetic diversification of Old-World marbled newts, with the description of a new and ‘ not-at-all-cryptic’ subspecies from the Iberian Peninsula (Triturus, Salamandridae), Contributions to Zoology 93 (2), pp. 127-152 : 149-150

Description of Triturus pygmaeus lusitanicus ssp. nov.

Description of the type specimen – adult male is in breeding access condition. Preserved under the on ethanol in excellent storage condition at the Museo Nacional de Ciencias Naturales, Madrid, under catalogue number MNCN 51799 . Measurements are SVl1 51 mm, SVl2 57 mm, ILd 25 mm, Hw 10.3 mm, Hl 14.9 mm, FLl 20.0 mm, TFl 6.0 mm, HLl 20.8 mm and FTl 7.7 mm. Total length 105 mm. Relative finger lengths 1 <4 <2 <3. Relative toe lengths 5 <1 <2 <3 = 4. Nlinks left 5, right 6, total 11; colour pattern reticulated. Thirteen crèmewhite bands over the head and body part of the mid-dorsal crest. Light grey ventral colouration, with an orange hue towards the swollen, deep black cloaca. Several roundish but vague ventral dark spots and many irregularly shaped medium large white spots. The type specimen is shown in Appendix fig. A2.

Description of paratypes

First paratype – MNCN 51800 Female . Excellent storage condition. SVl1 52 mm, SVl2 55 mm, ILd 27 mm, Hw 10.0 mm, Hl 14.7 mm, FLl 18.4 mm, TFl 5.8 mm, HLl 18.7 mm and FTl 6.8 mm. Total length 105 mm. Relative finger lengths 1 <4 <2 <3. Relative toe lengths 5 <1 <2 <4 <3. Nlinks left 3, right 6, total 9; colour pattern reticulated. Medium grey ventral colouration with no black spots and a medium number of small white spots.

Second paratype – MNCN 51801 . Female. Excellent storage condition. SVl1 58 mm, SVl2 61 mm, ILd 29 mm, Hw 10.8 mm, Hl 15.8 mm, FLl 20.0 mm, TFl 7.1 mm, HLl 21.3 mm and FTl 7.6 mm. Total length 120 mm. finger lengths 4 <1 <2 <3. Relative toe lengths 5 <1 <2 <3 = 4. Nlinks left 6, right 6, total 12; colour pattern reticulated. Grey ventral colouration with few small black spots and few small white spots.

Other material from the type locality – Additional morphological data on 11 individuals from the type locality are in the Appendix table A1.

Locality and date of collecting – Granja, Portugal, at 7.262 western longitude and 38.318 northern latitude, elevation 160 m above sea level. Collected by J. W. Arntzen on 11 March 2023.

Diagnostic features – the newly recognized subspecies is morphologically distinguishable from the southern, nominotypical subspecies by a high number of green coloured transversal bands (also referred to as ‘links’), by long fingers and toes in males and possibly by a relatively big head. Microsatellite data for a section of the range show a genetic profile that is drastically different from that of the adjacent southern form, as studied in the southern section of Doñana National Park.

Taxonomic status – The northern form is described as a subspecies. This decision is debatable because the currently available microsatellite genetic data suggest that genetic exchange with the nominotypical form in the short contact zone is absent or rare. The low level of genetic exchange may be due to a local environmental barrier, or to strong selection against hybrids.

Derivatio nominus – the subspecies name ‘lusitanicus’ acknowledges that the range of the newly recognized taxon coincides with the former Roman province of Lusitania.

Suggested vernacular name – Lusitanian pygmy newt.

Distribution – The south-western corner of the Iberian Peninsula with the exception of the Betic Cordillera. Approximate latitudinal range borders are the range of T. marmoratus at ca. 40 degrees north and the Guadalquivir to the south. In the east ranging till ca. 3.0 degrees west, perhaps 1.5 degrees west. Widely allopatric to T. p. pygmaeus , yet presumably with a narrow and sharp contact zone located inside the Doñana National Park. See figs 1 and 2.