Getting your steps in

 

A wonderful little millipede crossing the road.  If 10,000 steps/day are recommended for a person, how many steps/day are recommended for a millipede?  :) 

P.S.  This is probably Xystocheir dissecta.

Banded mystery

After finishing field work on 11 January 2020, we were walking up a trail when I saw this large invertebrate crossing the beam of my headlamp (it was ~8 p.m.):

 

It was ~6.5 cm (2.5 inches) long, which is sizable for a terrestrial invertebrate in this area.

I didn't know what it was, so I took a few pictures for the record.  At home, I did some searching on the Internet to try to figure out what it might be, but I didn't have any luck.  It was puzzling that such a striking invertebrate could be so hard to identify.

I thought it might be a beetle larva, but I couldn't find a good match online.  The days went by, but the memory of this mystery critter lingered in the back of my mind.  I tried online searches several more times, but with the same lack of results.  What was it?

Here are close-ups of the head and tail ends:

 

 

Last night I decided to submit a picture to BugGuide.Net to see if someone could help with the identification.  Not too long after, I received a response that it might be a beetle in the Phengodidae family.

I checked it out and it looks like a good match.  More specifically, this is probably a Western Banded Glowworm (Zarhipis integripennis).

I hadn't learned about this species before, but it's a fascinating beetle with a remarkable life history.  A few fun facts:

- Yes, they do glow!  But just not at the tail end (like a firefly), but at each of the segments, so there are luminous green bands along the back.  (Rather than being involved in courtship, the glowing might be defensive, signaling that the glowworms are unpalatable.)

- The adult males look like a fairly typical adult beetle (with very feathery antennae), but the adult females are completely different.  The adult females are "larviform," which means they look just like the larvae.

 - The larvae are voracious millipede predators.  The description of their feeding behavior was almost shocking to me.  It read like a lion attack on the Serengeti.  It's not for the faint of heart!  If you're curious: 

"When a Zarhipis larva discovers a milliped, it races alongside the milliped until it can mount its back...When mounted, the larva throws a coil around the milliped with its last abdominal segments and uses the tenth abdominal segment in an opposable manner to aid its grip.  It then stretches full length to reach for the most vulnerable part of the milliped's exoskeleton — the articulating membrane (where the main nerve is near the surface) between the head and the first body segment on the ventral side.  The larva severs the main nerve with its sickle-shaped mandibles, paralyzing the milliped."  (Tiemann 1967)

The glowworm larva then brings the paralyzed millipede underground, eats the head first and then proceeds to tunnel through the body of the millipede eating all of its soft parts and leaving only the hard exoskeleton behind.

We've seen lots of millipedes along the trail we were walking, but I had no idea they are sometimes being chased by glowworm larvae!

P.S.  If you're intrigued (and brave enough!), you can read more and see photos of these glowworms — glowing, attacking, feeding, mating, egg-laying, and more — in this paper:  Tiemann, D. L.  1967.  Observations on the natural history of the Western Banded Glowworm Zarhipis integripennis (Le Conte) (Coleoptera: Phengodidae).  Proceedings of the California Academy of Sciences XXXV: 235-264.

Pink and silver stripes

A close-up of another critter that I encountered in the rain last night:

 

The next view shows the head, with dark eyes and segmented antennae:

 

This is a very large millipede with wonderful pink and silver stripes.  I'd estimate it was ~2.5 inches long (7 cm) and ~1/4 inch (0.6 cm) in diameter.

 

While trying to identify this millipede, I found an Annotated Checklist of the Millipeds of California published by Rowland Shelley in 2002.  Do you want to guess how many species and subspecies of millipedes there are in California? (The answer is below the next image.)

 

There are 226 species and subspecies of millipedes in the Golden State.  Whew!  That's a lot of millipedes (and a lot of little legs running around California!).  

Unfortunately, the list didn't help me identify this particular millipede, so if you know which species it is, please don't hesitate to contact me.

Two by two

Early this morning we were searching for millipedes for Eric's class.  It rained all night, so it seemed like looking under the logs in the backyard might be productive (millipedes like humidity).

I turned a medium-sized log and was surprised to see clusters of small pink millipedes (ranging from 5-20 mm long) — I'd never seen a pink millipede before!  They were quite striking against the dark, damp beneath-a-log setting.  Beautiful, pale pink, and somehow soft looking when viewed from the kneeling height of a human.

 

After reviewing a few references, I think it might be Gosodesmus claremonti (although I'm open to insight from those more experienced with millipedes!).

Notice that this millipede has a flat back rather than the cylindrical shape of other millipedes.  It has a narrow body (a few millimeters wide).  Each tergum (segment) has two rows of prominent tubercles, or bumps (see below).

The segments have prominent paranotal flanges, sort of like flattened wingnuts.  They probably help to protect the legs (remember that millipedes have two legs/segment, hence their Class name = Diplopoda).

Note the small head, fuzzy face, and pair of simple antennae.

Sometimes I shake my head at how unaware I am about what's around us.  This is my eighth year in this house, and who knew there were amazing pink millipedes in the backyard?!