Golden Backed Ant Trapped by Cellar Spider

When my wife called me to our dining room to photograph a spider which has trapped an ant 10 times its size, I rushed to photograph this spectacle. It was true fight of David vs Goliath. The Golden Backed Ant (Camponotus sericeus) which was trapped in the Cellar spider’s web and was hanging upside down was unable to escape as it got tangled up more and more during struggle. The smaller sized spider was running all over the ant trying bite the ant. Position where this ant was struggling was an awkward one, it was flanked on onside by a window frame and on the other by the glass pane. So I could get only a few limited range of images of this struggle. I used Canon EOS 7D with Canon EF 100mm f/2.8L Macro IS USM with Canon MT-24EX macro twin light flash. All these photo are at minimum focal length and are uncropped.

The cellar spider or daddy longlegs (Pholcus species), are spiders of the family Pholcidae. Females have a body length of about 9 mm; males are slightly smaller. Its legs are about 5 or 6 times the length of its body (reaching up to 7 cm of leg span in females). Its habit of living on the ceilings of rooms, caves, garages or cellars gives rise to one of its common names. They are considered beneficial in some parts of the world because they kill and eat other spiders. Cellar spiders build loose, irregular, tangled webs in corners. They hang upside down on the underside of the web. The webs are not cleaned but instead a new web is continually added. This habit can result in extensive webbing in a relatively short time. The spiders and their webs are usually found in dark and damp places, such as cellars, basements, and crawl spaces. They can also be found in the corners of garages, sheds, barns, and warehouses, on eaves, windows, and ceilings, and in closets, sink cabinets, and bath-traps. Cellar spiders seem to fare better in areas with higher relative humidity.

Confusion often arises over its common name, because “daddy longlegs” which is also applied to two other unrelated arthropods: the harvestman and the crane fly. Pholcus have the habit of shaking its web violently when disturbed as a defence mechanism against predators. They can easily catch and eat other spiders (even those much larger than itself), mosquitoes and other insects, and woodlice. When food is scarce, they will prey on their own kind.

These spiders do not appear to be influenced by seasonal changes and breed at any time of the year. The female holds the 20 to 30 eggs in her pedipalps. Spiderlings are transparent with short legs and change their skin about 5 or 6 times as they mature. An urban legend states that Pholcidae are the most venomous spiders in the world, but this claim has been proven untrue. Recent research has shown that pholcid venom has a relatively weak effect on insects.

The Golden Backed Ant (Camponotus sericeus) is the commonest ant in India. There is a distinct pleomorphism in these ants with the major worker like the one in the picture here measures 8-10mm in length while the median workers are 5-7mm. Minor workers are tiny at 3-4mm spend most of the time inside the nest. Major workers are black and opaque with granular appearance their broad head and mesosoma. The antennae, tibiae and legs are dark castaneous red. Gaster has dense silky golden pubescence and in some individuals silvery pubescence is seen. The node of the petiole is rounded and knob like. Median workers are similar to Major worker with lighter colored legs and antennae. The forage individually and recruit nest mates by tandem running.

Nest entrance differ to suit the vertical gradient. In mountainous region, distinct from scrub savannah habitat, these ants construct chimney like nests, tangential to the slope above the soil, to prevent water rushing into their nests. On flat grounds as well as closed canopy deciduous habitats their nest openings are on level with ground layer. In evergreen forests where they are less abundant they nest in soil under leaf litter. They tend aphids and feed on the extra-floral nectar.

My heartfelt thanks goes to Spider India forum especially Javed Ahmed and Siddharth Kulkarni for helping me ID the spider and for the great book on ants “On a trail with Ants by Ajay Narendra & Sunil Kumar M”. If you are wondering what happened in the end, no, ant did not escape death.