Sunday, January 31, 2016

An Illustrated Life List: Dollarbird

International Edition!
From a visit to Khao Yai National Park, Thailand during our honeymoon visit eleven or so years ago. Our awesome tour guide Mr. Nine called it a Baht-bird, the best cross-cultural birding joke I've ever heard. Ok, maybe the only one I've ever heard, but still pretty amusing.
The Dollarbird, Eurystomas orientalis is a member of the roller family, the Coraciidae. Not a familiar family to me, there aren't any rollers in North America, where the bulk of my birding has occurred. The closest relatives we find here are in the kingfisher family, the Alcedinidae, with only the Belted Kingfisher, Megaceryle alcyon being widespread. Rollers and kingfishers are members of the order Coraciiformes, which contains two hundred plus species, the majority of which are found outside of the Americas.
 
 
 
 

Saturday, January 23, 2016

Dark Fishing Spider Pitcher

Dark Fishing Spider, Dolomedes tenebrosus (Nursery Web Spider family, Pisauridae) eating a fly at the bottom of a plastic pitcher. I discovered this scene as I was placing the pitcher under an apple cider press to catch the soon to be pressed cider. I'm glad I did. Not only did I save this arachnid from a fruity deluge, but I also got to share it and my excitement with the group of kindergarten students who were with me at the time.
It is not uncommon to find Dark Fishing Spiders away from water and indoors. Fishing Spiders might be mistaken for Wolf Spiders (numerous genera in the family Lycosidae). In general you can tell it's a Fishing Spider and not a Wolf Spider by the following features:
  • they rest with their legs flat
  • all eight eyes are the same size - not easy to see without magnification in my opinion
  • egg sacs are carried at the front - not always present
Dark Fishing spiders are fairly easy to keep in a small terrarium. To set the terrarium up, I use a moss or soil substrate, with a piece of bark or some other natural object as a hiding place. I mist the terrarium every day or two, making sure there are some droplets low on the sides for drinking (a shallow dish or lid could work too). I feed small to medium-sized crickets to the spider once or twice a week. After a month or two of observation, you can always let it go back under whatever sink or damp corner you found it in, if it doesn't get away first.
 

Sunday, January 3, 2016

Clavate Tortoise Beetle

I've had these photos of a Clavate Tortoise Beetle, Plagiometriona clavata around since this summer and I've been meaning to post them. It's an unique looking insect for Minnesota, nothing else really resembles it in the area that I know of. I've always found them on Bittersweet Nightshade, Solanum dulcamara, but they are known to feed on other plants in the nightshade family.
The Clavate Tortoise Beetles' odd appearance comes from its enlarged and flattened out elytra and pronotum. Elytra are the hardened fore wings found in all beetles (order Coleoptera) that extend back over the hind wings, which are used for flight, and the abdomen. In beetles, the pronotum covers the thorax, and in the Clavate Tortoise Beetles, it covers the head too. I think this feature is shared by all Tortoise Beetles (not to get all taxonomical on you, but Tortoise Beetles are classified in the Tribe Cassidini which is in the Leaf Beetle Family, Chyrsomelidae. Tribes are tough for me to keep track of, as they don't fit into the classic mnemonic King Phillip's Court Orders Fabulously Good Sandwiches - Kingdom, Phylum, Class, Order, Family, Genus, and Species).
Many species of Tortoise Beetles feature iridescent and metallic colors. Clavate Tortoise Beetles missed out on this fun though. To me, their coloration and texture resemble bird droppings. The dark pattern against the translucent background also has a a teddy bear appearance. So snugly bird droppings I guess.
Pictured above is a larva of the Clavate Tortoise Beetle. The larva is the slightly bristly green lump. The brown on top is a shield made from its own droppings and shed exoskeletons which is used to protect itself from potential predators. The fecal shield is held by an appendage at the end of its abdomen. Rather than acting as a camouflage, the shield contains toxins from the nightshade and deters potential. But I wonder about the adults; does their appearance provide camouflage by mimicking bird droppings? I didn't find any information about the appearances of adult Clavate Tortoise Beetles and its functions. No one else speculated that they might be a mimic of bird droppings. Other species of Tortoise Beetles can press themselves down tight to whatever surface they may be on when threatened by a predator, and some can change their color to some degree. There appears to be a study or two about the Clavate Tortoise Beetle larva, but not the adult stage.
I've seen these beetles now and then for years, but I just learned what they are this past summer. I was pretty excited, I shared the information with anyone I could when there happened to be Bittersweet Nightshade around.