DOI: 10.5281/zenodo.17236243
title: Table 1 in Evaluation of speculated reproductive habitat for Somatochlora calverti (Corduliidae), a rare and range-restricted dragonfly

description: Table 1. Descriptions for the environmental characteristics cited in over 10% of all 25 sources used in the review.
Environmental characteristicDefinitionSandhillA xeric forest community that is maintained by frequent wildfire regimes and is comprised mainly of longleaf pine (Pinus palustris), American Turkey Oak (Quercus cerris) and Wiregrass (Aristida stricta). This ecological community is largely concentrated within the southeastern region of the United States.ForestedCommunities other than sandhill such as mixed pines, second growth deciduous, or hardwood forests that ofen for the riparian areas of seepage streams in the southeast.Small streamStreams that are characterized by being both shallow (≤ 20-30 cm deep, on average) and narrow (≤ 3 m wide, on average).SeepageSeepage streams are formed by the slow percolation of groundwater into the stream channel which, in this region dominated by sandy soils, causes the water to be quite cool (~17–20°C) and clear and ofen means that even during times of heavy rain, the volume and velocity of flow remains low in these channels. In addition to the seeping of groundwater into the channel, most of these seepage streams also receive inputs from surface water erosion down the landscape, which scours a “V-shaped” ravine down into the stream.Sphagnum mossA genus of moss (phylum Bryophyta), whose distribution is largely concentrated in the northern hemisphere. This genus of moss tends to grow in large patches called “hummocks” that many species of Somatochlora nymphs (particularly in northern latitudes) are known to use as a source of refugia.SteepheadA unique type of seepage stream that is mostly restricted to the north Florida /panhandle type region of the southeastern United States. What makes steepheads unique among seepage streams is that when ground water percolates through these sandy soils, it becomes blocked at an impervious layer, typically clays, and the water begins to move laterally in a process known as groundwater sapping. This lateral movement erodes the sediment at the head of the stream and sediment from above falls to fill it. This continuous process creates a steep, U-shaped or amphitheater-like shape to the ravine and the head of the stream will migrate with this continual process. The result of these differences is that while seepage streams can be either perennial or intermittent in flow, steepheads are most ofen a perpetual water source and their steep-sloped ravines are like canyons on Florida’s otherwise flat landscape which provide a microclimate of cooler, more humid conditions with a denser/thicker canopy of more unique, typically northern-distributed flora (such as large Sphagnum hummocks) and fauna.Sand bottomStream beds that are predominantly composed of sand as opposed to other common substrates.Undercut banksA stream bank that vertically rises and overhangs the stream channel, which creates cover for odonates, particularly clingers like Somatochlora nymphs, to hide in. These can also be formed by the root balls of trees that are growing directly on the stream margin.
description: Published as part of Girgente, Hannah E. & McIntyre, Nancy E., 2024, Evaluation of speculated reproductive habitat for Somatochlora calverti (Corduliidae), a rare and range-restricted dragonfly, pp. 88 in International Journal of Odonatology 27 on page 88, DOI: 10.48156/1388.2024.1917274, http://zenodo.org/record/15555122