Bug of the Week

Ephemeral Pond Critters Revisited

The wonder of ephemeral pools is that they are populated by animals that take this annual disappearing act in stride—animals that are prepared to dry up with the pond or to get out of Dodge (timing is everything), and therein lie many tales. An astonishing array of animals use ephemeral ponds as a place to drink, hunt, and breed, but an ephemeral pond is a challenging place to call home. The still, shallow water warms quickly (which encourages speedy metamorphoses) but contains little oxygen.

Contemplating Insect Eggs

Most insects begin their lives inside an egg that’s been deposited near/onto/into the correct food source, in the correct habitat for the eventual young. The BugLady often photographs these eggs, but she didn’t know much about them.

Common Green Darner, the Rest of the Story (Family Aeshnidae)

Most of our Wisconsin darners are in the famously-confusing mosaic darner genus Aeshna. Common Green Darners are one of two species of Anax darners found in the state. Common green darners are, well, very common, not just here but across the country. And Central America. And Hawai’i. And Canada. And there are populations in Tahiti and the West Indies. And strong winds have blown individuals to Great Britain, China, and Russia. The other Anax, the stunning Comet darner (Anax longipes) is a rare visitor and even rarer breeder in Wisconsin.

More about Millipedes

Millipedes have two legs on each side of most segments; centipedes have one on each side. there are 12,000 described species of diplopods worldwide, divided into two sub-classes, 16 orders, and 145 families, but there may be 70,000 more species out there waiting to be described! North America has just under 1,000 species in 52 families.

Tree Aphids (Family Aphidae)

Tree aphids are so exquisite that it’s hard to remember that it’s an aphid. It’s the winged phase; non-winged individuals are, depending on the species, blob-shaped, sesame seed-shaped, or spidery-looking insects seen en masse, sucking juices from the tender parts of plants. Aphids are generally wingless until an overcrowded plant/deteriorating plant quality signals them to produce winged forms that can migrate to nearby vegetation.

Three Micromoths

Microlepidoptera are a big group of small moths. To some extent, it’s a grouping that’s determined by the size of the moth; there are some families that include both macro and micro species, and the families of the micros tend to be more primitive than those of the macros. The group is very diverse and includes a bunch of day-flying species, and the biographies of many have not been written. Remember—of the 18,000 or so species of Lepidopterans in North America, more than 11,000 are moths. Here are three (and a half) of them.

Asparagus Beetles (Family Chrysomelidae)

Two species grace our area, the Asparagus/Common Asparagus Beetle and the Spotted/12-spotted Asparagus Beetle. Both species overwinter as adults in hollow asparagus stems, or under leaf litter, garden debris, or loose bark, The Common Asparagus Beetle is the first to wake up, and it also feeds on the lacy leaves, which can defoliate and weaken the plant. It lays its eggs in rows of 3 to 8 on the new spears, leaves or flower buds. The 12-spotted emerges a little later in spring, and it also eats the spears and leaves, but its larvae concentrate on the fruits and don’t damage the plant. It lays one egg at a time on the leaves; the larvae hatch, head for the fruits, and burrow inside.

Leeches Revisited

Leeches are segmented worms. They have eyespots along the dorsal side of the first few segments (though their vision is poor) and a brain and a sucker at each end. They can’t hear, but they have a good sense of taste, and sensitive skin. Unlike their (mostly) terrestrial cousins, the earthworms, leeches are flattened in cross section; like earthworms, their bodies are soft but very muscular. All of the 700 or so known species of leech are carnivores.

Brown Stink Bug (Family Pentatomidae)

Brown Stink Bugs feed on leaves, stems, flowers, seeds, nuts, and fruits of a variety of plants, both wild and domestic. In fruit crops, their injected saliva may cause chemical damage, and their piercing may cause mechanical damage (holes) or cosmetic issues (scars on fruit). Brown stink bugs develop by simple/gradual metamorphosis, going from an egg, to a nymph that looks pretty much like an adult and that adds adult body parts as it grows, to an adult.

Water Lily Leaf Beetle II (Family Chrysomelidae)

The Water Lily Leaf Beetle is found throughout North America, wherever its host plants grow, and in northern Europe. They feed primarily on water lilies and smartweeds; each of the two distinct plant families presents unique feeding challenges, and it has been suggested that there are two, specialized races of WLLBs, with slightly different sizes, colors and jaw widths. A study in which larvae were mixed and matched with either food plant showed that not all host plants are created equal—beetles preferred, grew faster on, and had higher survival rates on their natal plants.