More than a decade ago, researchers in Crocker Range Park on the island of Borneo began a study to survey amphibians living in the forest. The team set up rows of plastic flags to guide their nighttime searches for frogs. Over three years, from 2003 to 2006, they walked these transects and documented frog species.
During their work, the researchers found a previously unknown frog hidden among fallen leaves. The new species is named Kalophrynus minutus. According to a study published September 3 in the Biodiversity Data Journal, Crocker Range Park is “one of the largest areas of relatively undisturbed rain forest in Borneo,” located within Malaysian territory.
“Previous samplings of frogs in the CRP have been carried out at relatively low elevations or at unspecified elevations,” researchers said. “The aim of our group was to carry out an inventory of the amphibians at specified low and high elevations. As has been shown at other sites in Borneo, repeated sampling of frogs reveals the presence of species not encountered during initial sampling.”
The scientists discovered K. minutus at around 3,900 feet above sea level in lower montane tropical forest habitats. They noted that these frogs live on soft soil or are slightly buried beneath leaf litter on the forest floor.
“Due to its diminutive size and leaf litter coloration, the species can be challenging to detect,” researchers said.
Kalophrynus minutus is described as small and stocky; males measure about 0.8 inches long while females are slightly larger at 0.9 inches. The frog’s head is wider than it is long, with narrow fingers ending in large rounded tips connected by fleshy webbing at their bases.
Their upper body color ranges from tan to beige depending on lighting conditions, with lighter undersides. Photos show that a dark patch on their backs resembles an outline similar to another frog with splayed back legs.
K. minutus is currently considered the smallest member of its genus based on its size characteristics mentioned above.
The study included a checklist documenting all frog species identified during three years of research; K. minutus was the only newly identified species among them. This brought the total number of known frog species in Crocker Range Park from previous counts up by forty additions—now totaling sixty-three different types recorded within park boundaries.
“Each new survey in CRP discovers additions to the known fauna, which makes it likely we have not yet reached the full count of frogs for this park,” researchers said. “It is not possible to say now how many species of frogs may actually occur in the CRP, but surely there are many more than previously thought.”
Crocker Range Park lies in northern Borneo within western Malaysia’s jurisdiction and continues to yield new findings as studies continue into its biodiversity.
The research team responsible for this discovery includes Paul Imbun, Tan Fui Lian, Maklarin Lakim and Luiza Majuakim.
