Thursday, July 31, 2014

Rio Grande Chirping Frog

Rio Grande chirping frog, Eleutherodactylus cystignathoides
The Rio Grande chirping frog is a terrestrial frog that lays its eggs in moist soil and leaf litter. As complete metamorphosis occurs within the egg, they are extremely well adapted to the urban environment. The native range of these frogs is extreme south Texas along the lower Rio Grande Valley; however, populations have been unintentionally introduced in other parts of Texas as well as Louisiana and Mississippi through potted plant trade. Outside their natural environment, they are often found in crevices near buildings. During rainy weather, their loud call can often be heard in clusters.

Although mentioned twice in the past, the Rio Grande chirping frog remains one of my favorites.

Tuesday, July 29, 2014

Black Widow Eggs

Southern Black Widow Spider, Latrodectus mactans, constructing egg sac.
The Southern black widow spider, as mentioned before, is the most common of the native widow spiders and considered the original black widow. Mating often occurs in spring or summer, as contrary to common misconception, sexual cannibalism is rare in nature with reports from cramped laboratory settings. The female constructs an egg sac which contains 25 to 250 eggs, and can produce more than one sac over the course of summer. The females guard the egg sac until hatching about 4 weeks later. Once hatched, the spiderlings disperse by ballooning silk threads and allowing air currents to transport them away.

Thursday, July 24, 2014

Green Lynx Spider

Green lynx spider, Peucetia viridans
A bright green spider often found on shrubs and flowers, the green lynx spider is the largest lynx spider in North America. They can be found throughout the southern United States and as far south as Venezuela and can also be found in the West Indies. While the females may reach up to 16 mm (5/8 in) in length, males are smaller at 13 mm (1/2 in), but both have the bright transparent green body with prominent pale legs.

While green lynx spiders feed on beneficial insects, they also feed on pests.
Although docile towards humans, green lynx spiders are known for aggressive predation. They are active, arboreal hunters, but will sit quietly for prey when the optimal spot is found. As the common name lynx implies, they hunt like a cat and pounce suddenly on their prey. Their prey include butterflies, bees, wasps, and caterpillars, as efficient at removing other beneficial insects as it is removing pests from the garden. Aside from spitting spiders, the green lynx spider is the only spider that can squirt or spit venom.

Tuesday, July 22, 2014

Milkweed Butterflies

Queen Butterfly, Danaus gilippus
While Monarch butterflies are the most well-known and recognized of the milkweed butterflies, there are many others including queen butterflies. As with others found within the tribe Danaini, the larvae feed on a number of milkweed species, obtaining the toxic cardiac glycosides that are retained into adulthood. The colorful caterpillars and distinctive pattern on the wings of adults are warnings to predators of their poison. A mass migration of Monarchs occurs from August until October with a distinctive eastern and western population. The eastern population overwinters in central Mexico whereas the western population spends their winters along the California coast. Queen butterflies migrate as well, but to a lesser extent as they mainly stay in warm climates year round.

Want to help monarch populations and preserve the migration? Be sure to plant milkweed, but be positive it is the milkweed they need. While adults will often feed on the nectar of any milkweed, the larvae feed exclusively on milkweed that contains the glycosides and not all milkweed is suitable for larvae. In short, avoid "butterfly weed" and other non-milky milkweeds if you want caterpillars.

Thursday, July 17, 2014

Black and Yellow Garden Spider

Black and Yellow Garden Spider, Argiope autantia
Not to be confused with the banana spider, the black and yellow garden spider is a type of orbweaver found as far north as southern Canada and as far south as Costa Rica. The females of this species range between 19 to 28 mm (3/4 to 1 1/8 in) while males are smaller at 5 to 9 mm (1/4 to 3/8 in). Although spiderlings hatch in early spring, this species is more readily noticed in late summer and autumn when mature.

Typical web and zigzag pattern of a black and yellow garden spider.
Black and yellow garden spiders prefer sunny areas among flower, shrubs, and other tall plants with little to no wind to build their webs. The web is circular as is typical of other orbweavers. While the juveniles create a circular stabilimentum, heavy webbing, in the center of the web, adults create a vertical zigzag band above and below the middle of the web. They wait for prey such as mosquitoes, yellow jackets, and grasshoppers to become trapped in the web before paralyzing it with venom before digesting it. They are most active during the day with females able to consume prey twice her size. While they can bite, they are non-aggressive, and their venom is not dangerous to humans.

Tuesday, July 15, 2014

Black Widow

Southern Black Widow Spider, Latrodectus mactans
The Southern black widow spider, sometimes considered the original black widow, is the most common of the native widow spiders and can be found throughout parts of Canada, the east coast, the Great Plains, and within all four deserts of the American southwest. Its scientific name, Latrodectus mactans, is a mixture of Greek and Latin meaning "murderous biting robber." Common belief of is that widow spiders kill and consume their mate following copulation; however, the practice was mainly observed in a crowded laboratory setting. The current thought is sexual cannibalism is the male's inability to escape, not the female's interest in cannibalism. As cobweb spiders, they construct irregular structures in dark, undisturbed areas near the ground. For that reason, care must be taken when working in dark areas that have been undisturbed for some time. While all spiders produce venom, few have the dose or means to be considered dangerous like the female black widow. Worldwide, only three moralities have been attributed to widow spider bites, and no known cases of death by envenomation by a widow species within the US has been reported. Envenomation often causes sharp muscular pain anywhere from 15 minutes to hours after the bite depending on bite sight. Severity and radiation of significant pain increases for several hours before gradually passing off in two to three days. Although antivenin is available as treatment, acute hypersensitivity reactions are a concern for many victims. If antivenin is not given or unavailable, relief for pain and muscle cramping is given until symptoms pass.

Edit: For more information on the venom, antivenin, and how to obtain venom to make antivenin, please check out my Google+ post which goes into further details.

Tuesday, July 8, 2014


Another week of hiatus. Until then, enjoy this photo (shot with my phone) of a wasp killing a cicada. While I need to look into it, it is actually a paper wasp and not a cicada killer. When checking hours later, the cicada was found hollowed out with a paper wasp crawling around inside. Paper wasps are known to feed soft-bodied invertebrates to their young, such as caterpillars, but the cicada incident is new to me.

Thursday, July 3, 2014

Assassin Bugs

Wheel Bug (Instar), Arilus cristatus
Assassin bugs, mentioned many times before, are the largest of the true bugs, the Hemiptera order of insects. The key difference of distinguishing true bugs are their specialized mouth parts, proboscis, that are used to suck fluids. For an assassin bug, this beak is used to inject toxic enzymes into their prey to paralyze, kill, and dissolve the insides for consumption. While this also means they will deliver a painful bite if poorly handled, they are considered beneficial to gardens as they kill a number of pests.

Another busy day and so another short, summarized visit to one of my favorite insects.

Tuesday, July 1, 2014

Standing Cypress

Standing Cypress, Ipomopsis rubra
Standing Cypress, also known as Texas plume, red Texas star, flame flower, Indian plume, Spanish larkspur, and red gilia, is a stiff, unbranched biennial that can reach up to 1.3 m (4 ft) in height. Although native to the southeastern portions of the United States, it has been reported as far north as Canada. It blooms from June to August in dry, sandy, or rocky soils. The showy red flowers are attractive to hummingbirds.