Beetles: it's what's for breakfast—at least for the red widow spider of Florida's "scrub" habitat, according to a study by University of Missouri biologist James Carrel.
The study provides a first glimpse at the diet of this mysterious spider, revealing that it primarily preys upon species of scarab beetles common to the scrub habitat. Carrel's findings shed light on red widow spiders' restriction to the Florida scrub habitat and the need for habitat conservation efforts.
Latrodectus bishopi gets its name for the reddish-orange coloring of its head, carapace, and legs. Although venomous, no bites from this spider have been recorded.
Credit: James Carrel
"The pine scrub habitat, found on sandy ridges in Central and Southeastern Florida, is one of the oldest in North America," said Carrel, Curators Professor Emeritus in the MU Division of Biological Sciences. "Many of the plants and animals found on these ridges, including the red widow spider, are restricted to these high, dry areas. Our research suggests that red widows have evolved to specialize on scarab beetles because they are reliable food sources."
Carrel said that red widow spiders are difficult to study due to habitat confinement and the hidden nature of their webs, which are built in palmetto shrubs. Red widows conceal their funnel-shaped retreats in unopened palmetto leaves, making them difficult to spot. The only clues to the spiders' presence, visible solely on foggy mornings during four months of the year, are the threads spun loosely between tips of palmetto frond.
Since 1987, Carrel has been monitoring populations of this spider at the Archbold Biological Station, which protects a 5,193-acre Florida scrub preserve near Lake Placid. Only twice in those 23 years – in March 1989 and in May 2003 – have enough webs been located to study the dietary habits of these elusive spiders. The scientists identified 43 species of insects among the 98 specimens collected. The study revealed that the primary prey of the spider, especially in early spring, are five species of scarab beetles endemic to the Florida scrub habitat.
"The scarab beetles, which often are larger and stronger than the spiders themselves, fly just above the tops of scrub vegetation," said Mark Deyrup, senior research biologist for the Archbold Biological Station, who co-authored the study. "Sometimes beetles hit the web strands between tips of palmetto fronds and tumble into the denser tangle of threads below, catching them in the red widows' webs."
Carrel has monitored red widow spider populations at the Station since 1987, but has found enough webs to study red widows' dietary habits only twice. During both time periods, Carrel worked alongside Deyrup to collect and identify prey from spiders' webs.
Carrel's study, entitled "Red widow spiders prey extensively on scarab beetles endemic in Florida scrub," appeared in the March issue of the Florida Entomologist. Funding for the study came in part from a grant from the University of Missouri in Columbia, MO.
Jeff Sossamon | EurekAlert!
Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory
How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy