Journal archives for March 2018

March 04, 2018

Observation of the Week, 3/3/18

Our Observation of the Week is this Giant Pill Millipede (not a pillbug), seen in Madagascar by @damontighe!

This observation is one of over 1,800 that Damon Tighe made on a recent trip to Madagascar, currently more than any other iNat user. Armed mainly with his iPhone, a cheap clip-on macro lens and a small DIY moth light, he documented quite an array of wildlife and even spread some iNaturalist love to the guides there.

“Madagascar is vast country with varied topography and is a little larger than [my home state of] California,” says Damon. “Its early break-off from Africa 160 million years ago and subsequent isolation after breaking off from the Seychelles and India 66–90 million years ago has allowed for a diversity of organisms that is incredible. Famous for lemurs and chameleons, the country offers so much more than these iconic charismatic critters.”

And one of those charismatic critters, of course, is the bizarre Giant Pill Millipede. Damon recalls,  

I saw my first Sphaerotheriida my second night in Madagascar at Andasibe and I spotted it while cleaning up from an all-nighter with a moth light that just before dawn brought in one of the largest moths in the world, Argema mittrei...The last thing I expect a millipede to do is roll up into a tight unopenable ball, but in Madagascar millipedes in the Order Sphaerotheriida do just that!

Giant Pill Millipedes range from Southern Africa into Asia and to Australia and New Zealand, but the largest ones reside on the island of Madagascar, where island gigantism has caused some species to achieve the size of an orange when rolled-up! Like other millipedes, they are detritivores who feast on rotting plant matter, but because of their unique defensive posture these many-legged creatures don’t excrete toxic substances to ward off predators, as most other millipedes do. When rolled-up, the dorsal plates on their second and last segments interlock, allowing the millipede to relax its muscles and still maintain its posture.

Guides are compulsory in Madagascar’s national parks and reserves (“They have a wealth of knowledge, especially around charismatic fauna.”), and Damon (above, sporting an Argema mittrei moth) introduced a few of them to iNaturalist:

I met a few guides who had smartphones and I brought along a handful of clip-on macro lenses to give them. I showed them the basics of iNaturalist and with these two tools in hand some of them turned into passionate explorers, reveling in all that they could document, and all that they still had to learn about organisms right around them. I'm working with one guide in Isalo National Park to be the point person for the distribution of a bunch of macro lenses and little cards that explain how to use iNaturalist since the park receives the most visitors of any in Madagascar and wifi access is readily available at a number of places in the adjoining town.

- by Tony Iwane

- A different order of millipedes, Glomerida, also roll-up into balls, but these live primarily in the Northern Hemisphere and are much smaller, reaching lengths of about 20 mm (0.79 in).

- Here are a few Giant Pill Millipedes in various states of defense.

- Slugs of the family Chlamydephoridae are known predators of Giant Pill Millipedes.

Posted on March 04, 2018 01:15 AM by tiwane tiwane | 0 comments | Leave a comment

March 12, 2018

Observation of the Week, 3/12/18

Our Observation of the Week is this amazing look at a Sahara Sand Viper, taken by @abdellahbouazza in Morocco!

Sand dunes present both an interesting challenge and an opportunity for legless predators like snakes. In order to move swiftly across the loose and often hot surface, vipers from both the old world and new world evolved the sidewinding form of locomotion. And for ambush predators like the above Sahara Sand Viper photographed by Abdellah Bouazza, the sand provides excellent opportunities for hiding.

A PhD a Marrakech University, Abdellah is a herpetologist who’s currently focusing “on some ecophysiological (thermoregulation, reproduction) and biogeographical aspects (distribution and conservation) of amphibians and reptiles in Morocco and others Mediterranean areas.”

In the spring of 2017 he and some friends traveled to southern Morocco in search of snakes. They visited the sandy areas of Khenifiss National Park and, after finding some other reptiles, also chanced upon the “beautiful small sand viper, Cerastes vipera (30 cm) during the first hours of the night” Abdellah explains that the coastal population of this snake differs morphologically from others, “with contrasted or dark brown colour patterns and bright orange eyes. It lives in coastal dunes from southwestern Morocco in sandy plateaus on the edge of the Atlantic Ocean.”

With most of its body buried, the Sahara Sand Viper can both protect itself from the heat of the day and lie in wait for prey. However, it isn’t just a passive hunter: it lures prey by twitching the tip of its tail above the sand, then strikes when the rodent or lizard (or bird) is close enough. Like all vipers it is venomous and has retractable fangs. You wouldn’t want to get bitten by one, but its venom is not typically considered fatal to humans.

Abdellah (above, holding a snake) explains that “[when teaching] I enjoy showing students nature, her importance, and I hope to pass on my knowledge and passion to the next generation. I try to combine scientific research with creating awareness about the biodiversity around us.”

He only recently joined iNaturalist, but says that it “contributed my interest in sharing records of my observations and paying attention to my research subjects and biodiversity around me. Also, I can share my observation with several experts who are happy to help in determining some unknown species for me.”

- by Tony Iwane

- Abdellah has his own website and Flickr page. Check them out!

- On this trip Abdellah went with some friends from Atheris. They captured incredible video of a Sahara Sand Viper from Morocco here.

- On a personal note, I was lucky enough to see some perfect Sidewinder rattlesnake tracks in the Mojave Desert a few years ago. When sidewinding, the part of the snake touching the sand does not actually move, leaving impressions like these.

Posted on March 12, 2018 09:38 PM by tiwane tiwane | 0 comments | Leave a comment

March 18, 2018

Observation of the Week, 3/18/18

Biting midges feast on the hemolymph of a Giant Golden Orb-weaving Spider while it in turn sucks the juices from a wasp - this is our Observation of the Week! Seen in Singapore by @budak.

Parasites are, as we all know, a fact of life. And while we don’t often think of spiders as having them, budak’s photo shows that our eight-legged friends do have to deal with blood-sucking hitchhikers - just like the rest of us.

budak is a self-taught naturalist, who “grew up near forests, rivers, [and] mangroves in Malaysia” and has volunteered at the Lee Kong Chian Natural History Museum in Singapore as well as participated in citizen science activities like Seagrass-Watch and the Comprehensive Marine Biodiversity Survey. He’s also the top iNaturalist observer in Singapore, having logged over 4,700 observations of 670 species! He uses iNat “as a 'repository' and an aid for identification/education thanks to the many experts for different taxonomic groups.”

Of course, one way to up your observation and species count is to find situations like flies feeding on a spider feeding on a wasp. budak recalls coming across this scene while on a photo walk in the Labrador Nature Reserve. “These large but harmless spiders are fairly common by trails/forest fringes in the region,” he says. “I saw this individual feeding on a scoliid wasp and wanted to take a closer look/shot, which revealed many biting midges on the cephalothorax.” His observation was originally published here, “although Art Borkent later shared that he believes the midges are Atrichopogon not Forcipomyia” explains budak.

One of the largest orb-weaving spiders in the world, female Giant Golden Orb-weavers can grow to body sizes of about 5 cm in body length and 20 cm if you include the legs. Males, however, are tiny - maxing out at 5-6 mm body length! Immensely strong, the silk of this spider is golden in color and females use it to build webs over a meter in diameter. Not only can they be parasitized by flies, but small kleptoparasitic Argyrodes spiders steal small prey from the large golden webs.

Whether the flies on this spider are Atrichopogon or Forcipomyia, they would be classified as biting midges of the family Ceratopogonidae. Called “no-see-ums” in North America and “midgies” in Scotland, biting midges are often considered pests to humans, as their bites can cause itchy welts. It is unknown if the spiders get itchy when bitten...

- by Tony Iwane

- Golden orb-weavers are just so cool. Some males deposit silk on the female when courting, and some females have been known to kill and eat birds.

- Golden orb silk has been woven to make an incredible textile that was on display at the Art Institute of Chicago. It was quite a process.

Posted on March 18, 2018 11:51 PM by tiwane tiwane | 3 comments | Leave a comment