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Drosera ×bockowskii Scholl, a new nothospecies, is the first successful hybridization between Drosera capillaris and Drosera filiformis.

Normal Drosera tracyi plants occasionally produce individual leaves with slightly forked ends, (usually < 25 mm deep). Very rarely, groups of individuals may be found within otherwise normal populations that appear genetically inclined to exhibit regular and extreme forking of their leaves. Plants from seed or leaf cuttings of these carry on the trait and it appears that the trait may eventually be developed even further by selective breeding.

Measurements in the field on dry days indicate that when the traps of Dionaea muscipula (Venus’ flytraps) close, they capture prey about 40% of the time at one site and 44% at another. The 60% and 56% of traps that close but do not catch prey reach their maximum closure on average in about 10 minutes, begin reopening in about 7 hours and completely reopen in 22 hours. Traps that have captured prey tighten along their rims, sealing the lobes and forcing the margins outward into a “narrowed” condition that takes 4 to 6 hours to achieve. Reopening of narrowed traps begins, on average, after 9.2 days and they are fully open in 12.8 days. A few traps that capture large prey never reopen. In dry weather closure frequency of traps capable of closure was low, averaging 3.5%/day at one site and 3.1%/day at another. At both sites the capture frequency of traps capable of closing was only 1.4%/day. The low frequency of capture, and high percentage of closures that result in capture, indicate that the low capture frequency is due to a low number potential prey entering and triggering the trap rather than a low efficiency of capturing the prey that enters. Traps that close, but fail to capture prey, have been observed to be triggered by insects, spiders, snails, and even toads that were far too large to be captured. A few captured beetles have been observed to force their way out of trap lobes. Dionaea traps capture prey at all hours of the day. The capture frequencies are variable and are not significantly higher in any specific time period. Both nocturnal and diurnal animals were captured.

Dionaea muscipula traps, in a natural setting, are sometimes triggered to close without capturing prey. In the Florida panhandle, in dry weather, time-lapse photographs show the frequency of closure without capture to be 2.1 closures/% of active-traps/day. A sudden burst of intense rain can increase this by two to three orders of magnitude for a brief time. Frequencies of 15.5 closures/% of active-traps/hour and 148 closures/% of active-traps/hour have been measured. The large increase in closures occurs when rain first starts, because the most exposed and most sensitive traps are triggered early, leaving traps in a more sheltered position and those with a less sensitive response open. Only 6 to 12% of the traps in the field of view were closed by intense rain. Even rain so heavy that the traps were submerged in water left most of the traps open. Gentle rain can close traps, but this is not a common event. The necessity of two or more stimuli to close a trap accounts for traps general lack of responsiveness to raindrops in light rainfall. Traps observed to be closed by raindrops began reopening in an average of 4.5 hours and full reopening averaged 15.8 hours. Since partially open traps are capable of capturing prey, the average trap closed by rain is effective at trapping in about 12 hours. Rainfall is only a minor factor interfering with traps’ ability to catch prey.

Trail cameras can be used for the study of the interaction between plants and insects if they have a close-up lens and the capability of doing time-lapse photographs or videos. Typical trail cameras are mounted vertically, often on unstable camera stands. We have used the Bushnell NatureView HD Cam Model# 119740 and RC Williams Co. TopView Quick-Mount camera-stand to study the behavior of insects interacting with Venus flytraps (Dionaea muscipula). The combination allows photographs and videos to be made of insects and plants from above, with the camera held in a position that allows the plants to be observed from the exact same position for months at a time. Every five minutes a photograph and a one-minute video are recorded. We have developed methods of searching through this data for important events that involve producing “slide shows” of the photographs overlain by a grid, that can be quickly scanned for events of interest. Video of these events near the time of the sequentially numbered photograph can then be viewed. The slides and videos can also be sampled at intervals for more gradual changes.

Dionaea flowers are pollinated by insects, primarily bees, in both their native habitat in the Carolinas and in the population growing from seed scattered many years ago in the Florida panhandle, the location of this study. The green sweat bee (Augochlorella sp. is a major pollinator in both habitats, while various flower visiting beetles play a prominent role in the Carolinas and bumblebees (Bombus sp.) play a major role in the Florida population. Flowers open in late morning and pollen is on anthers arrayed directly above the center of the flower by 11:30 EST. Twenty-four hours later the stamens have bent so that the anthers are at the periphery of the flower and the stigma has expanded, presenting a papillate surface receptive to pollen. Insects visit the flower between 11:30 EST and 18:00 EST. Rewards for pollinators are pollen and nectar from glands at the base of the petals. Possible attractants include the bright white radially symmetrical corolla with radiating grey veins, and on the second day, the radially displayed stamens that may act as a 'nectar guide'. No markings on the petals are visible in the ultraviolet light but the pollen-laden anthers are UV-fluorescent and would stand out as a ring of dots to any UV-perceptive insect.