The results of the City Nature Challenge CHWP BioBlitz are in!

On Saturday, April 30, the Friends of the Wilderness Park held a BioBlitz in the Claremont Hills Wilderness Park as part of the City Nature Challenge. (If you don’t know what a BioBlitz is, please check out our previous post.)

The City Nature Challenge official identification period is now over, and we are excited to report our results.  (Although if you have observations you haven’t posted yet from the BioBlitz, don’t worry, they will still be counted.)

Southern Bush Monkeyflower (Diplacus longiflorus). Observation by ©Vicki Salazar.

Overall results

Eight observers made 197 observations of 95 different species during the BioBlitz.  Eighty percent of the observations reached “Research Grade”, which means that the iNaturalist community agreed on species-level ID, with more than 2/3 of identifiers agreeing on the species ID. You can see all the observations from the BioBlitz by clicking here.

Most observed species

Not surprisingly – since it’s at its showy peak right now – the most observed species was Southern Bush Monkeyflower (Diplacus longiflorus).

New species observed

Most exciting to us was the addition of 14 new taxa to our Biota of the Claremont Hills Wilderness Park project.  They included:

San Luis Blazingstar (Mentzelia micrantha). Observation by ©Carol Blaney.
A Western Aphideater (Eupeodes fumipennis) – a syrphid fly. Observation by ©Carol Blaney.
  • Four plant species:
    • Southern California Clematis (Clematis pauciflora)
      This means we have two Clematis species in the Park
    • Pineapple-weed (Matricaria discoidea)
    • San Luis Blazingstar (Mentzelia micrantha)
    • Perennial Ryegrass (Lolium perenne)
      We’re not so excited about this non-native invasive grass, but it’s good to know it’s there
  • Nine insect taxa (1 bug, 4 beetles, a wasp, and 3 flies):
    • Aoplonema – a plant bug
    • Judolia sexspilota – a flower longhorn beetle
    • Ornate Checkered Beetle (Trichodes ornatus)
    • Apsena – a darkling beetle
    • Dichelonyx– a May beetle or Junebug
    • White-headed Bee Fly (Bombylius albicapillus)
    • Euodynerus – a potter wasp
    • Chrysopilus – a snipe fly
    • Western Aphideater (Eupeodes fumipennis)
  • One bird species:
    • Hutton’s Vireo (Vireo huttoni)
      You can listen to it here

Coolest observation

Vegetarian bugs go rogue and try to make a meal of blister beetles!

A mirid plant bug (Aoplonema sp.) attacking a Red-eared Blister Beetle (Lytta auriculata). Observation by ©Carol Blaney.

“Coolest” is, of course, subjective, but our pick is Carol Blaney’s observation of a pair of mirid plant bugs (Aoplonema sp.) attacking two mating Red-eared Blister Beetles (Lytta auriculata).  As she describes the encounter, “The Aoplonema pair advanced on the mating Lyttas. One mirid repeatedly probed the tarsal claws of the female, which she twisted away to avoid, as best she could while mating. The other probed the underside of the male Lytta (as shown in this photo).

What made this encounter strange is that the attacking bugs were mirids = plant bugs.  Aren’t they supposed to eat plants?  What were they doing going after blister beetles? A tip from identifier K. Schneider pointed us to the answer.

It turns out that some mirids are predatory and eat other insects, and that Aoplonema are particularly attracted to blister beetles.  These aptly named beetles secrete a compound, cantharidin, which causes severe blistering on the skin and is poisonous when ingested. Cantharidin is generally a defense against predators, and blister beetles coat their eggs with it to deter predators. Paradoxically, cantharidin is an attractant to Aoplonema. They use it to home in on blister beetles and then proceed to insect their mouth parts membranous regions between segments of the blister beetles’ hard exoskeletons to suck out their hemolymph.  Yikes!  It truly is a dog-eat-dog – or in this case a bug-eat-beetle – world out there!

The link to the observation with all the fascinating comments is:

Many thanks to:

  • All the folks who staffed our booth – Vicki Salazar, Meg Mathias, Scott Marnoy, Diego Tamayo, Glen Morrison, Drew Ready, and Nancy Hamlett.
  • All the observers who contributed their sightings – Carol Blaney, Dave Bedell, Donna Bedell, Vicki Salazar, Carson Barry, Mark Coast, Laura Roach, and Nancy Hamlett
  • All 43 identifiers!