Brachymeles gracilis (Fischer, 1885)
Brachymeles gracilis likely represents a complex of morphologically similar species. Over the last several years, an effort to understand the diversity of this genus has resulted in a doubling of the species diversity, with many of the previously recognized species complexes being revised. To date, Brachymeles gracilis remains a widespread species spanning islands of the Mindanao Pleistocene Aggregate Island Complex. It is a medium-sized species with five fingers and five toes. Populations vary greatly in digit numbers, scale counts, and numbers of presacral vertebrae. Two subspecies are currently recognized: Brachymeles gracilis gracilis and Brachymeles gracilis hilong. Brachymeles gracilis gracilis is recognized to occur throughout much of central and western Mindanao Island, while B. g. hilong is recognized from Samar, Leyte, and eastern Mindanao islands. The genus Brachymeles represents a unique group of semi-burrowing (semi-fossorial) lizards in that the group possesses species with a full spectrum of body forms, from limbed species with five fingers and five toes, to fully limbless species. Researchers are interested in the process and patterns behind the evolution of these drastic changes in body form. With the exception of two species from Borneo (B. apus) and Thailand (B. miriamae), all species of Brachymeles are endemic to the Philippines. This means they are found among the more than 7,000 Philippine islands and nowhere else in the world.
Brachymeles gracilis can be distinguished from congeners by the following combination of characters: (1) body size moderate (SVL 59.9–82.3 mm); (2) limbs pentadactyl; (3) Finger III lamellae four or five; (4) Toe IV lamellae 7–9; (5) infralabials six or seven; (6) supralabials six; (7) suparciliaries six; (8) supraoculars five; (9) midbody scale rows 24–30; (10) axilla–groin scale rows 44–50; (11) paravertebral scale rows 66–73; (12) pineal eye spot present or absent; (13) prefrontals contacting or not contacting on midline; (14) frontoparietals contacting or not contacting on midline; (15) mental/1st infralabial fusion absent; (16) enlarged chin shields in three pairs; (17) nuchal scales undifferentiated; and (18) auricular opening present.
We have evaluated this species against the IUCN criteria for classification, and find that it does not qualify for Critically Endangered, Endangered, Vulnerable, or Near Threatened status. Brachymeles gracilis has been documented to have a broad geographic distribution and is quite abundant at all sampled localities. We therefore classify this species as Least Concern, LC (IUCN, 2010).
SVL 59.9–82.3 mm
Ecology and Distribution
Brachymeles gracilis is recognized to occur in the Mindanao Pleistocene Aggregate Island Complex.
- Senira bicolor (part) Gray, 1845 (synonym)
- Eumeces (Riopa) gracilis Fischer 1885:85 (synonym)
- Brachymeles gracilis Boettger, 1886 (synonym)
- Brachymeles gracilis Boulenger, 1887 (synonym)
- Brachymeles gracilis Taylor, 1917 (synonym)
- Brachymeles gracilis Taylor, 1918 (synonym)
- Brachymeles gracilis Taylor, 1922a (synonym)
- Brachymeles gracilis Taylor, 1922c (synonym)
- Brachymeles gracilis Brown & Alcala, 1970 (synonym)
- Brachymeles gracilis Brown & Alcala, 1980 (synonym)