Emerging from the underworld

They’re back. Cicadas are crawling out of the hypogeal darkness. Summer must be coming, hidden somewhere behind the cold, rainy clouds.

Cicada emerging 009 This pallid nymph was hauling itself out of a hole in the trail. The front legs are mole-like: sharp-edged shovels. After the insect’s molt, which usually happens shortly after emergence, the shovels will turn to grappling hooks, a more elongate form suited to clambering in trees. The molt will also equip the adult cicada with wings (wing buds are visible on the nymph’s back in the photo above).

Cicada emerging 013This is a so-called “annual” cicada, a name that belies the two or more years that the nymph has spent below ground. Although individual cicadas take more than one year to develop, there are multiple cohorts present in every location, so at least some of them emerge every year. This contrasts with the “peridocial” cicada species whose cohorts are synchronized, emerging every thirteen or seventeen years. Sewanee had one such emergence back in 2011. The New York region is due for an emergence this year, so we can expect some cicada media coverage in the coming weeks. (To find out whether or not you’re in the emergence area, see here for maps of the various “broods” of periodical cicada — the NY brood for 2013 is Brood II.)

13 thoughts on “Emerging from the underworld

  1. Anonymous

    David, re the periodical cicadas: 13 and 17 are prime numbers; wonder if cicadas think in primes? Or those may be periods that are difficult for predators to synchronize to. Jill

    Reply
    1. Anonymous

      That’s every 221 years they emerge together. That happened here in Black Jack MO in the nineties. It was cool. Last time it happened here was in the 1770’s!

      Reply
  2. Jackie Donnelly

    I live in northern NY, so I will be listening. What great bugs! I love cicadas, whose buzzing call spells summer to me. I had never seen the nymph stage before. Thanks for posting the photo.

    Reply

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