eTawau > Insects of Borneo > Beetles > A straight-snouted weevil at Bandar Sri Indah

A weevil with a straight nose

A straight-snouted weevil beside the Babanga Stream, on the River Esplanade of Bandar Sri Indah, in June 2014, when the stream still ran

It was a thin black line on a leaf, crawling slowly towards the tip and on over the end of it, as if it had no particular place to go. Up close it turned out to be one of the oddest-shaped beetles you can meet on a Tawau walk: a weevil, but long and straight as a matchstick, with its nose drawn out in front and its antennae held straight ahead of that.

A long, narrow black beetle crawling along the upper side of a narrow green leaf held between the photographer's fingers, towards the curled tip. Its head is drawn out into a long snout with straight antennae in front, and its body is many times longer than it is wide. The forest floor and trees behind are out of focus.
This is what you would see. The River Esplanade, Bandar Sri Indah, 7 June 2014, 2.49 in the afternoon. My fingers are holding the leaf steady; the beetle was not touched.

A weevil, but not the usual kind

The same beetle a minute later, head-down at the tip of a leaf, with six labels: the tips of the wing cases split into two points; the wing cases finely grooved lengthways; the long, narrow, neck-like segment behind the wing cases; the eye; the long snout; and the straight, bead-like antennae hanging below, which are not elbowed.
The same beetle a minute later, head-down at the tip of the leaf. 2.50 pm. Cropped and labelled; nothing else altered.

Most weevils are easy to recognise: a snout, and on the snout a pair of antennae that bend in the middle like an elbow. This beetle has the snout but not the elbow. Its antennae run straight out in a line of short, bead-like segments. Put that together with the rest of it:

That combination belongs to the straight-snouted weevils, family Brentidae. They are a mainly tropical family, and many of them live on or under the bark of dead and dying trees, where the long thin body slips easily into cracks and tunnels.

How far the name goes. The family is safe on the characters above. Genus and species are not determined: the family is large in the tropics, and the genera are separated on details of the snout, the antennae and the males' bodies that these two photographs do not show well. The record has been posted to iNaturalist at family level, where specialists can take it further.

Why the snout matters

In brentids the snout is a tool. Females use theirs to bore small holes in wood, and lay their eggs in them; the larvae then feed in the wood. In many species the males' snouts are built differently from the females', and males of some species use theirs in contests over mates. Without seeing the underside, this page does not say which sex this one is.

How big — not measured

There is nothing in the frame to give a scale, and this camera, a Panasonic DMC-LX5, does not record a focus distance, so this record has no size. The fingertip in the first photograph is not at the same distance from the lens as the beetle, so it cannot be used as a ruler either.

Photograph and leave. Brentids are harmless. This one was photographed where it was crawling, with the leaf held steady, and left on its plant.

The record

7 June 2014 · 2.49 to 2.50 pm · beside the Babanga Stream

Crawling on the leaf of a plant beside the River Esplanade

River Esplanade, Bandar Sri Indah, Tawau, Sabah. Bandar Sri Indah is 17.2 km from Tawau, measured from the 0 km Tawau landmark, and the esplanade is about another 1 km from its shopping centre. It runs beside the Babanga Stream, which comes down from the Babanga Forest Reserve. One beetle, black, not measured, crawling slowly and apparently aimlessly on the leaf of an unidentified plant. Long snout; straight, bead-like antennae; long narrow neck-like segment behind the head; wing cases finely grooved, their tips split into two points; legs slender and dark. Coleoptera: Brentidae — a straight-snouted weevil. Genus and species not determined. One only. Two frames, 14:49:14 and 14:50:26. The leaf was held steady for the first; the beetle was not touched and was left where it was.
— iNaturalist observation 403223112

The stream that has gone

In 2014 the Babanga Stream was still flowing with clear water from the hills, and the strip of forest along the esplanade was full of insects, dragonflies and spiders. By 2026 the stream had dried up, and much of the life along the esplanade has gone with it.

So this beetle is a record of a place as it was. Nobody can go back to that stream bank in 2014 and photograph what lived there, and a dated photograph of an ordinary insect turns out to be one of the few kinds of evidence that survive. The story of the esplanade itself, from its opening in 2007 to its dry stream bed today, is on the River Esplanade page.

Words you may meet

Brentidae
The straight-snouted weevils. Weevils with straight, not elbowed, antennae, usually very long and slender, mostly tropical.
Weevil
A beetle whose head is drawn out into a snout, with the mouthparts at its tip.
Rostrum
The scientific word for the snout.
Elbowed antenna
An antenna with a long first segment and a sharp bend after it, like an arm bent at the elbow. Most weevils have them; brentids do not.
Elytra
The hard front wings of a beetle, which close over the back as wing cases.

Related pages

About the photographs. Two frames by Wong Fook Yee with a Panasonic DMC-LX5 in square 1:1 mode, no flash, f/2.0, ISO 100, 5.1 mm, taken at 14:49:14 and 14:50:26 on 7 June 2014 on the River Esplanade of Bandar Sri Indah, Tawau, Sabah. Both are camera originals that have never been opened in an editor. For this page they have been reduced, cropped and labelled; nothing has been sharpened, recoloured, added or removed. The unmarked full frames are on the iNaturalist record above.

The family characters and the account of how brentids use the snout are from the general entomological literature. The locality, date, times, behaviour and the drying of the stream are the photographer's own observations. The plant is not identified. Distances from Tawau on this site are measured from the 0 km Tawau landmark using Google Maps. All photographs © Wong Fook Yee. Page written 25 September 2026.