Tuesday, 30 September 2008

A Darkling Beetle

.....Saragus costatus

Whilst in hot pursuit of a small but agile skink, I was removing a few rocks among which it had crawled. My attention was then shifted to the interesting looking beetle you see photographed below. It is 15mm in length and I believe it to be Saragus costatus, one of the Darkling beetles of the Tenebrionidae family. As was the case with this one, these beetles are often found under rocks or among leaf litter. Most likely, it was laying low, waiting to come out at night to feed. Most of the Tenebrionids feed on rotting plant and fungal material although the larvae of this particular genus are root feeders. Along with several other genera they are listed among the False Wireworms which, coincidentally, I mentioned here just a couple of days ago. Another coincidence is that I last saw this species almost a year ago to the day and only a few feet from where this one was located.

Tenebrionidae is a very large family with over 1500 species in Australia. "The Catalogue of the Insects of Tasmania" lists 82 species here in Tasmania including the well known pest of stored grain, the Mealworm. My first post on this blog showed the full life cycle of the Mealworm Tenebrio molitor. It can be viewed here.

(Click Photos to Enlarge)
Saragus costatus - Dorsal View

Saragus costatus - Frontal view

Saragus costatus - Ventral view


  1. Hi Mosura.
    Just on the timing issue you mentioned (same time, same place, last year). I had a similar experience today - answering a query today about a plant which I had posted a photo of on October 1 last year.
    And my Tree Peonies are flowering within days of when they flowered last 2 years. So are the village;s Cherry Trees.
    Certain timings are dependent upon weather patterns. Others, the more stable ones, probably work on daylight length. And, you can set your calendar by them, year after year.
    Interesting beetles, by the way. I have not seen such rounded ones as those.

  2. The underside of the feet look like they've been dipped in gold paint I think!

  3. Thats a mean looking beetle Mosura. Good sharp pics too.

  4. That's a familiar beetle Mosura, now I'll be able to call it by name!

  5. Thanks Denis, Jenny, Warren, & Duncan - Thanks for your comments ...and yes, phenology is always fascinating.