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Rain Beetle Season 2015-2016

We’re enjoying our second rain storm of the season here in Northern California. I hadn’t really thought much about rain beetles this year, but in the past day I’ve had several emails and a couple of phone calls from folks asking about them. So I guess it’s time to start up the thread for another season. Here is the thread from last year.

The topic of this thread is Rain beetles. Think of this thread as a place to discuss your rain beetle forays, encounters, or whatever. This year, let’s try to keep the photos out of the thread proper. Use clickable thumbnails to include rain beetle photos which you’ve already posted to the guide. Any other useful photos, particularly those of habitats, let’s post somewhere else and then include the links in this thread. The Complete Markup Article has all the information you’ll need for creating clickable thumbnails or links to off-site photos, but feel free to contact me if you’re having difficulty.

BugGuide has photos now for all the described species of Pleocoma, but is still missing photos of females for many of those species.

Rain beetles can be caught at lights (black lights, mercury vapor, you name it). They can be found floating in puddles or ponds. You can even determine whether you have rain beetles in your area by examining coyote scat. If you live where the rain beetles live, as I do, all you have to do is turn the lights on in your home and open the door before dawn on a rainy morning. The beetles will fly right into your house!

Happy beetling!

Pleocoma octopagina Robertson 1970
I had a couple colleagues report that in Late Jan. and Feb. 2016 they had success in getting some Pleocoma octopagina males around Wrightwood and Cajon Pass . GST

Robert Walker Spammer

Already reported
It will be gone soon.

He won't be able to keep his junk up...
Taken care of :)

Pleocoma rubiginosa rubiginosa Hovore 1972
On Feb.12th and 13th 2016 , I went down to the Southern Sierra's at Kennedy Meadows in Tulare County and set out my home made vein traps for a couple days .I then collected a nice series of Male Pleocoma rubiginosa rubiginosa in the air with net and the black lite traps. Snow melt was the trigger and lows of 34 with a high of 58 degrees. GST

Pleocoma rubiginosa rubiginosa and transierra still flying !
Just got back from several days in the back county between Kennedy meadows and Mt Whitney area . Saw several male Pleocoma rubiginosa rubiginosa and Pleocoma rubiginosa transierra still flying at the higher elevations with the Snow line melting around 7,000 to 10,000 feet . The main runoff and flight is past, however they will continue to " Perculate " out of the ground- as it thaws and the melt water gets to specimen under ground chamber. I saw a couple dozen fresh coyote scats full of elytra and coyote dug holes for males and females . Due to low numbers, Have black lites to get them, the net is fine... however you see them very fast and far from you. Cheers ! Gene St. Denis

Pleocoma rubiginosa transierra Hovore 1977
I headed down to Bishop Creek area at about 6,000feet on Feb.11,2016 and set out my black lite vein traps.I got one male transierra that flew right by me and starting digging in the ground for a female. I dug up the area and received no female and keep the male. I then got a second male. Warmer Temps and Snow Melt were the Trigger. GST

Pleocoma hoppingi Fall 1906
Two days ago solo , I drove down from Tahoe very carefully on 88 and then 49 thru the storms to Hwy 108 out of Sonora in the western Sierra's . Then turning east I headed up 108 Past Twain Hart to around 4,900 feet on turn outs and Put up my home made Black light vein traps and waited . 6:00am to 6:45 am were the ticket for flight times. I kept a very nice series of active males and dumped out a couple hundred or more to repopulate the species. A giant puddle collected almost twenty for me ! 48 degrees and raining . Snow and dirt were 50/50 .49 had an Big rig tipped over with twenty Firefighters, and CHP s trying to the folks out of the destroyed cab in the dark rain. The Semi Blocked All traffic north and south for over 4 hours and I had to go back , up, and around 50 miles to get around the major Clog . And that is my Rain Beetle trip report .Gene St.Denis

Rumor has it, there were coyotes out and about....

Coyotes feed at Blacklite traps .
Yes,this true... I had a couple of Wet , Hungry, and Growling Coyotes raid 2 traps and I had to pick up an Oak branch to ward them off. As if you needed anything else... to happen on a soaking wet dark night in different territory. An I thought 49 was tough. GST

Pleocoma linsleyi
I made a long and tiring field trip thru the storms , down to L.A. Co. in search of Pleocoma linsleyi Hovore 1971 with Joe Eguivabal from Reno Jan. 14 and 15, 2016 . We hit the Mt. Pinos and Sanberg areas with Excellent results ! With Black lite s out at 5 to 6:45 am and some very resent wet rain soaked ground we encountered very good numbers of flying males of linsleyi and a couple Pleocoma badia males as well. Gene St. Denis

Yogi was right
The season isn't over 'til it's over!

2015 Season
Hey there Brady and Gene.. I sure wish I'd been out and about with you on 2015 ventures. It's been a while. I appreciated the bugs you've shared with me... big time.

Glad we could help !
Good to see you back in the action ! gst

Still not
too late....

Any of these in the Santa Monica Mountains, Los Angeles?
But we haven't had any moisture for many, many months, so I don't know how that affects them.

Pleocoma puncticollis Rivers 1889
I collected Pleocoma puncticollis males in 1969 at the Mullholland Drive drive bridge with 2 black lite s and the bridge lite s in thick rain . They were my first Pleocoma with area local recommended by Frank Hovore, himself ...... Personally .To get there, I rode my bike from Hawthorne, calif. north to 405 and mullholland drive bridge .....and back , in the rain . I got back Home to the warm and dry bed time to catch the bus for school ! Frank, He got me started in an Amazing a city full of Chaos and lost souls .... at any rate ...... Happy New Year to All ! May you All hold onto a True and Steady Course in Life ! Hope that helps ....Cheers, GST

Rain Beetles in Santa Monica Mts.
I think there are. They've been collected from vicinity of San Diego Fwy (405) near Mullholland Dr. I recall seeing a photo a few years ago of a bucket trap with beetles from Santa Monica Mtns. As Brady mentions Ian Swift has the data..

Not sure
I don't have any records at hand of Pleocoma from the Santa Monica Mts, but there are localities just to the east in and around LA and also to the north and west (Ventura and Santa Barbara). It wouldn't surprise me to see them show up in the Santa Monica Mts. I know very little about the SoCal rain beetles. Ian Swift would likely have a more definitive answer to your question.

I was in the LA area in September just before the torrential rains and flooding. I wonder if a lot of the species emerged then? I haven't heard any reports, though. I'd say any rains might bring them out, if they haven't emerged already.

I guess they can't afford to be too picky
in a climate like this. Maybe the September rains did encourage them.

Must say I wasn't aware of any floods in September. I remember that week though, we had some rain for about 7 hours, and another hour the next day, but that's all. We miss a lot of the "drama" in downtown LA and Orange County up here, though we are still part of LA.

I guess the question is if they didn't emerge in September, will they just keep waiting for rain to come, or will they just emerge anyway when it gets to a certain point in the year, even if there is no rain?

Again, not sure
The rain beetles in my neck of the woods will start emerging during the first good soaking rains. That's usually in October. We sometimes have a dry spell for up to a month and I've seen rain beetles emerge again after these dry spells. One year, the first emergers came out around October 5th, then little rain until December and the last ones were in late December.

On further thought, I think the September (early October?) flooding I'm remember was farther to the east and north of you -- maybe Kern County or even northern LA County?

Just thought I'd mention....
I watched a re-run of 'Quincy' today. They used a Pleocoma species to pinpoint the location of a crime! They said something like, 'this is pleocoma xxxxxx, it rained in the San Bernardino mountains over the weekend, and these beetles appear after a rain' (sorry that I didn't catch the species mentioned).

Rain Beetles on TV
Ha!! Interesting...

Very Cool!
I watched Quincy during it's initial airing, but that was well before I went into Entomology. I'll have to track that one down and see if they got it right. Thanks!

Do you remember the title of the episode or maybe the name of a guest star?

Found it.....isn't the internet amazing

My searches didn't yield any luck. Now I need to watch the episode!

Pleocoma hovorei
I found a couple Pleocoma hovorei-males under lites at Paynes Creek ( lite rain ) 11/15/2015 . gst

Pleocoma hovorei
This morning, I hit a small flight of this species in the same general area as Gene's location above.

Pleocoma hovorei La Rue
December 4th and 5th I collected some more Pleocoma hovorei males under lites- both mornings in the Paynes Creek area . First thing in the morning 6:00am to 6:45 am in light rain . 21 mm to 29 mm lengths . gst

Pleocoma hovorei La Rue 2007
Pleocoma hovorei still flying .I recieved a nice series of males from Paynes Creek area once again with my Home Made Blacklite Plexiglas Vein Traps . Heavy rain 48 degrees, with lite winds ( 12/8/2015) . gst

Pleocoma hovorei
This species was still flying in the Paynes Creek area on Sunday, 12/19. As an added bonus, I ran into a fellow rain beetler that morning!

Pleocoma simi
Went up to hwy 44 just south-east of shingle town ,( west off hwy 89 ) and pulled out off a dirt road in heavy rain . Setting up my home made Blacklites I waited and started to get a nice series of Flying Pleocoma simi - males between 5:25 am to 6:35 am on 11/15/2015 . Awesome golden brown Fuzzy Butt Nuggets !! 49 degrees . gst

Pleocoma "near simi"
This species was still emerging as of yesterday morning in the Shingletown area. I found 2 beetles floating in puddles, most likely from the pre-dawn flight.

Pleocoma simi ( near) Davis 1934
Pleocoma simi (near) still flying , as I received a another Very Nice series of Males with my homemade Plexiglas Veined Lite Traps near shingletown ! 44 degrees and Heavy rain at 4 oclock , started getting males at 5:00am until 6:45 am slow but steady (12/8/2015). Lite wind . males were 25 mm to 34 mm. gst

Pleocoma fimbriata Le Conte 1856
On Nov.2,2015 I stopped by Pine grove , hwy 88 store,market lites and Hwy lites and found a hand full of dead Pleocoma fimbriata males . lite rain . gst

Pleocoma blaisdelli
I headed down to 49 and Don Pedro Reservoir 11/3/2015 ( during our first heavy soaker rains ) and set out a couple of my home made Plexiglas vein Black lite bucket traps and waited . 56 degrees Rain. Finally the lord sent down more rain and at 5:00 am to 6:10 am a very nice series of males newly hatched , very sharp horned , and scratch free ! Very Shiny black elytra covers and golden brown Fur ! I'll post visual jpg. pics on Pleocoma blaisdelli spot later . The males lengths were exactly ( on metal calipers ) 20 mm to 28 mm long. I Looked long and hard.... but... no Females .....isn't that always the case ! ...... Anyway , too you Pleocoma Addicts ..... " Cheers to all" and " Good Hunting "! gst

Don Pedro Beasts
Hey there Gene, Brady shared a few of your beasts with me. THANKS! Nov. 3, my birthday... a nice gift..

P. blaisdelli Linsley 1938
You deserved it John ! I look forward to seeing you in the field ! Have a Nice New Years as well for you and Yours ! Hope you got some of the "Puddle Newbies" as well. Cheers, GST

Pleocoma fimbriata
I hit a large flight in Oregon House, CA tonight. They flew between 5:30 and 6:00 pm.

Pleocoma staff
Today saw the first flight of Pleocoma staff here on the Ridge above Chico, CA. I only had 4 males fly in to both front and back porch lights, all between 6:02 and 6:04 am. We've had just under an inch of rain in the last 24 hours. I suspect there will be flights for the rest of the week, even if it doesn't rain.

2nd Day
Another flight of P. staff this morning. It lasted a bit longer than yesterday's flight: 5:45-6am. Clear skies, but there are piles of hail left from last night's thunderstorm. The air temp this morning was hovering around 33F. Several beetles flew past the light without stopping, so I suspect there were females out and about today.

9th Day
I forgot to post yesterday that Pleocoma staff continues to emerge here in the foothills above Chico.

14th Day
We had a nice storm move through northern California this morning/afternoon and the Pleocoma staff emerged here at home yet again. I was off elsewhere standing in the pre-dawn rain getting skunked.

Done for the year?
Despite several good days of rain in the mornings the past few days, I've seen no more P. staff here at home. I suspect the beetles I saw on 11/15 were the last emergers of the season in my area. We had low temperatures for nearly two weeks with no rain. Several other species in Northern California continue to emerge, though.

Pleoocoma fimbriata males-Oct. 17+18, 2015
I headed out in the First Fall Heavy ground/ soil Water saturation rain storms the last few days in the High Sierra's looking for Pleocoma flights. I finally found a very flight of Pleocoma fimbriata males on Highway 88 at 3000 feet (or so ) in two small cute little community's of Pine Grove and Pioneer . At night the local stores and Business's Lites and 5 of my Home made 12 volt black Lite Plexiglas vein traps provided the collection of a very nice number of small males and some Beautiful Shiny Black and Large Lumbering Males with long blonde fur ! The Ground soil was soaked down over a foot . During the day I would look for dead/ downed males around lites ( found several) and female burrows ( found None ) . Located over 50 very, very Flat road kills . The Dogs, Cats, Coyotes, and Raccoons were very happy with the new Tasty and Interesting Buzzing and dawdling Snacks ! Good start for 2015 . God Bless all ! gst

First hemolymph
Exciting news! Our rains here in the foothills east of Chico have been few and far between. We haven't had a good soaker yet so I don't think P. staff emergence has started.

Pleocoma fimbriata male lengths
Brady, the main bulk of the Pleocoma fimbriata male body lengths ranged from 22 mm to 35 mm exactly on calipers . gst

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