Leyte is the eighth largest
island in the Philippines and is considered a site of high biodiversity and
conservational importance, particularly the forested mountainous interior of the
island. The island was formed by volcanic activity along the Philippine Trench
(a subductive plate margin, where one tectonic plate is being forced below
another and melted by the heat of the Earth’s interior, with some of the
resultant magma rising through the overlying plate to form volcanoes), during
the Pleistocene, when it was attached to Greater Mindanao Island. As such it
has rich volcanic soils and a fauna and flora made up entirely of species that
have colonized during or since the Pleistocene or evolved in situ since this
time. Leyte has a tropical climate wet all year round, with the southern part
of the island having a distinctive period of higher rainfall between November
and April. Despite being an area of acknowledged biogeographical and conservational
importance, much of the interior of Leyte remains unexplored by biologists.
In a paper published in the
Raffles Bulletin of Zoology on 14 April 2015, Tony Robillard of the Muséum national d’Histoire naturelle in Paris and Sheryl Yap of the College of Agriculture and Museum of Natural History at the University of the Philippines Los Baños, describe two new species of Eneopterine Crickets as part of a study
of this group on Leyte Island. Eneopterines are small Crickets with distinctive
mating signals, noted for their high diversity on the islands of the Pacific
and the Philippines in particular.
The first new species described
is placed in the genus Lebinthus,
which is known from the Philippines, Indonesia and Singapore, and given the
specific name estrellae, in honour of
Regene ‘Estrella’ Portillo, who helped with accessing the locality where the
species was discovered and with collecting specimens. The species is described
from three male, sixteen female and four juvenile specimens collected in
secondary rain forest on a slope at Barangay Villa Corazon near Burauen in the
interior of Leyte Island, as well as one male captured as a juvenile at the
same location and raised in captivity.
Lebinthus estrellae: (A) Female
and (B) juvenile specimens in leaf litter secondary forest, Barangay Villa
Corazon. Robillard & Yap (2015).
Lebinthus estrellae is smaller than other members of the genus, and
dark brown in colour with white and yellow markings and a lighter orangish or
pinkish brown band on each eye. It was found living in small bushes and leaf
litter in secondary rain forest. The males produced a short trilling song with
83-91 sylables.
The second new species described
is placed in the wingless genus Paranisitra,
which is known from the Philippines and offshore islands of New Guinea, and
given the specific name leytensis,
meaning ‘from Leyte’. The species is described from two male, six female and
four juvenile specimens collected from secondary rainforest at Barangay Villa
Corazon and Buo near Burauen in the interior of Leyte Island.
Paranisitra leytensis, new
species: (A) Female and (B) male specimens in natural habitat near Burauen,
Leyte. Regene Portillo in Robillard & Yap (2015).
Paranisitra leytensis is considerably smaller than other members of
the genus, with the males being notably smaller than the females. The adults
are yellow- or grey-brown, with black and white markings, these differing
between the sexes. Juveniles are colourful, with green red and yellow patterns,
later instars developing the adult colouration.
Paranisitra leytensis, juvenile
specimen in dorsal view. Scale bar is 1 mm. Robillard & Yap (2015).
See also…
Katydids (or Buschcrickets), Tettigonioidea, are Members of the Insect Order Orthoptera, which also includes Crickets and Grasshoppers. They are voracious eaters and can consume a...
Katydids of the genus Xizicusand its close relatives are found across eastern Asia, though the taxonomy of the group is currently somewhat confused, in part due to publications being published in different languages...
Follow Sciency Thoughts on
Facebook.
