Salvin's mushroomtongue salamander  (Bolitoglossa salvinii)

Classified as Endangered (EN) on the IUCN Red List (1).

Belonging to a diverse group of amphibians known as the lungless salamanders (Plethodontidae) (4) (5) (6) (7), Salvin’s mushroomtongue salamander is a strikingly coloured amphibian, its black body marked with an orange to reddish or purplish-brown band along the back, edged with a wavy yellow border and with variable and irregular black spots (8) (9). A relatively large and robust species, with well-developed limbs, it has a long, thick, prehensile tail, an adaptation to the species’ arboreal lifestyle. The large, fully webbed hands and feet are also thought to give good grip when climbing (3) (4) (5) (6) (8) (9).

As in other lungless salamanders, the female Salvin’s mushroomtongue salamander grows larger than the male, although males tend to have a broader head, longer legs, and larger hands and feet (6). Breeding males also possess an enlarged ‘mental gland’ under the chin, which is rubbed on the female’s body during courtship (6) (7). All lungless salamanders are characterised by the presence of a distinctive shallow groove, known as the ‘nasolabial groove’, which runs on each side of the head from the nostril to the edge of the upper lip, and serves to carry chemical signals from the ground to the nasal cavity (4) (6) (7).

Salvin’s mushroomtongue salamander has been recorded from the upper coastal plain on the Pacific slopes of southern Guatemala, as well as from one location in El Salvador (1) (8) (10) (11).

This species originally inhabited forest, including dry forest and lowland wet forest, but with the loss of these habitats from much of its range it is now most commonly found in shaded coffee and banana plantations, and in sugarcane fields (1) (8). Salvin’s mushroomtongue salamander has been observed climbing on Heliconia leaves and other large-leafed plants (3), and has been recorded at elevations of around 600 to 1,250 metres (1) (8) (10) (11).

An active, climbing species (3), Salvin’s mushroomtongue salamander feeds on small invertebrates, such as insects. Prey is captured using the remarkable projectile tongue, which can be shot out at great speed to strike moving prey at some distance away (3) (4) (6). If attacked, Bolitoglossa species may arch the back and wave the tail, and can even shed the tail if it is grasped by a predator (4) (6). As the group’s name suggests, lungless salamanders are unusual in lacking lungs, meaning that these species must instead absorb oxygen through the skin and the mouth lining (4) (5) (6) (7).

Salvin’s mushroomtongue salamander is likely to be active year-round, with breeding potentially taking place at any time of the year (4). The male salamander produces a gelatinous packet of sperm, known as a spermatophore, which, after successful courtship, is picked up from the substrate in the cloaca of the female (7). Fertilisation then occurs inside the female’s body (4) (7). Female Bolitoglossa salamanders typically lay small clutches of eggs in damp places on land. The eggs may take several months to develop, and hatch directly into miniature versions of the adult rather than going through a larval stage (1) (4) (5) (6) (7).

Salvin’s mushroomtongue salamander was once relatively common, but has undergone a decline as a result of the loss and fragmentation of its forest habitat, mainly due to subsistence agriculture and wood extraction (1) (8). Since lungless salamanders need a damp environment to maintain the moist skin on which oxygen uptake depends (4), any alteration in moisture conditions poses a severe threat. Therefore, although it still survives in shaded plantations and sugarcane fields, any clearance of these to create more open, drier habitats would have a negative impact on this species (1). Similarly, climate change may also pose a threat, and already appears to be causing dramatic declines in other Central American salamanders (12). Although there is not yet any direct evidence that the fungal disease chytridiomycosis has contributed to these declines, its role in the decline of many other amphibian species suggests that it may also be a potential threat (12).

No specific conservation measures are currently known to be in place for Salvin’s mushroomtongue salamander, but the maintenance of shaded habitats has been identified as being important to its long-term survival (1). The species may potentially occur within the Parque Nacional El Imposible in El Salvador, although this is not yet confirmed. It is not currently known from any protected areas in Guatemala, but a number of protected areas have been proposed within its range and may benefit the species in the future (1).

Efforts to understand the causes of global amphibian declines have so far focused mainly on frogs, with relatively little attention on salamanders. However, the severe declines observed in many Central American salamander species has highlighted the need for increased understanding and protection of these unusual and intriguing amphibians (12).

To find out more about the amphibians of Guatemala see:

• Reptiles & Amphibians of Guatemala:
  http://www.uta.edu/biology/campbell/guatemala/

For more information on amphibian conservation see:

• IUCN / SSC Amphibian Specialist Group:
  http://www.amphibians.org/
• Amphibian Ark:
  http://www.amphibianark.org/
• Gascon, C., Collins, J.P. Moore, R.D., Church, D.R., McKay, J.E. and Mendelson III, J.R. (2007) Amphibian Conservation Action Plan. IUCN/SSC Amphibian Specialist Group, Gland, Switzerland and Cambridge, UK. Available at:
  http://www.amphibians.org/ASG/Publications_files/ACAP.pdf