Summertime Skimmers

The female Comanche Skimmer looks very different from the male (pictured below).

The heat of the summer is often a good time to search for dragonflies, specifically the skimmers, which comprise the largest family of dragonflies.  They are generally the most obvious, too, as they are frequently seen around ponds lakes, and streams, and perch conspicuously on twigs, bushes, and branches. 

Skimmers are often large and colorful with distinctive wing patterns, and many species of skimmers are sexually dimorphic, meaning the males and females of the same species are different in appearance.  Males frequently develop pruinescence or exhibit a frosty or dusty-looking coating when mature, while most females have little to no pruinescence at maturity.  In our area, some of the less common species include the Gray-waisted Skimmer (Cannaphila insularis), Checkered Setwing (Dythemis fugax), Needham’s Skimmer (Libellula needhami), and Comanche Skimmer (Libellula comanche).

The male Gray-waisted Skimmer has greenish-blue eyes, a face that is white in front and metallic blue on top, and a dark thorax divided by several pale stripes.  The wings are clear except for dark extreme tips, and the abdomen is black on the back half and pruinose gray or white on the front half, which gives rise to its common name.  Females and juveniles have reddish-brown over blue-gray eyes, and the abdomen is yellow or orange with brown or black in between segments.  These skimmers prefer shady, marshy ponds, lakes, and streams, particularly those with cattails or tall reeds, and are on the wing from June to September.

Gray-waisted Skimmer, male

From mid-April to mid-December, you can find Checkered Setwings, as they are widely distributed and sometimes locally abundant.  The male has bright red eyes and face, a reddish-brown thorax with obscured dark stripes, and clear wings except for a large patch of brown coloring near the base.  The abdomen is black with two pairs of pale streaks at the base of each segment, giving it a checkered black-and-white appearance. Females and juveniles are similar, but often have a paler face and a pale thorax with narrow dark stripes.  These setwings favor slow-flowing streams and rivers, ponds, and generally open areas with tall vegetation but little canopy.

Checkered Setwing, female

Male Needham’s Skimmers have reddish-orange eyes and face, thorax orange in front and paler on sides, and wings that have orange veins along the leading edge and clear along the trailing edge, giving them a somewhat bicolored appearance.  The abdomen is reddish-orange with a dark dorsal stripe down its length.  Females and juveniles have brown eyes and a pale face, yellowish thorax, and abdomen yellow throughout with the same dark dorsal stripe as the male.  On the wing from late April to early October, this skimmer prefers marshy ponds and lakes, and is often found perching low on vegetation surrounding or overhanging the water.

Needham's Skimmer, male

Comanche Skimmers can be found on the wing from May to mid-October, around springs, seeps, and sluggish areas of clear-running streams.  The male has aqua-blue eyes, a white face, and both thorax and abdomen with a uniformly blue pruinescence.  The wings are clear but for a bi-colored black and white pterostigma, a group of specialized cells in the leading edge of the wing towards the wing tip.  Females and juveniles have reddish-brown to pale blue eyes and a pale face, a cream-colored thorax with broad dark shoulder stripes, and a mostly yellow abdomen with a broad dark dorsal stripe running down the length.

Comanche Skimmer, male

Brave the heat during these hot months of the year and take a walk around a pond, stroll along a stream, or be on the lookout when on the lake, because you just might see one of these interesting summertime skimmers!

Undervalued Vines

  The uncommon Plateau Milkvine is often mistaken
for the more common Pearl Milkvine (above).

Every species of native plant has its purpose, and while many are valued by humans for their fragrant flowers and foliage, those that are valued for their role in keeping the earth’s nutrient cycles intact should be regarded as having the highest value.  Those nutrient cycles need to be protected through plant preservation or restoration, as they are what provides nourishment for the lifecycles of our native wildlife and protects the health of our ecosystems.

Even among those folks who are familiar with many native plants that perform this role, there are some little-known species that are often overlooked and under appreciated.  In Central Texas, there are a few species of vines in the Milkweed family that many fail to notice, including Star Milkvine (Matelea biflora), Plateau Milkvine (Matelea edwardsensis), and Bearded Swallow-wort (Cynanchum barbigerum).  

Star Milkvine, also called Purple Milkweed Vine, is a relatively common vine that grows in pastures, prairies, and other open ground, usually in chalky soil throughout Central and North Texas.  This small, trailing vine to 2 feet has five-petaled, star-shaped, deep purplish-brown flowers that are 0.5 inches wide.  Blooming from March to June, the flowers occur in pairs along the trailing stems that radiate from a central rootstock, and arise from the axils of the opposite, triangular leaves.  The flowers, leaves, and stems are all quite hairy, as is true of many members of the Milkweed family.  Its habit is to grow low among grasses, often in areas that are mowed, so it is frequently passed over by humans, but is a useful host plant for Queen and Soldier butterflies and a nectar plant for several species of bees.

Star Milkvine has low-growing stems that radiate out
from a central rootstock.

The unusual flowers of Star Milkvine occur in pairs.

Soldier

Sometimes mistaken for the more common Pearl Milkvine, Plateau Milkvine is a vine to 3 feet that is endemic only to the Edwards Plateau of Central Texas.  This uncommon vine shares the same twining habit of Pearl Milkvine, but its leaves, while similar, generally have a somewhat wavy edge, and its flowers are bell-shaped instead of flat. Additionally, its 0.7 inch wide greenish-white flowers do not have a pearl center, and its petals are not solely reticulate-patterned, having parallel veins in their lower halves and centers, and reticulate or networked veins only on the edges or margins.  Blooming in April and May, this vine can be found on gravelly soils in open woodlands, often climbing on other plants, and is a native host plant for Queen butterflies.  Due to indiscriminate land clearing, this plant is listed as ‘vulnerable’ in terms of its conservation status in Texas.

Plateau Milkvine is a rare cousin to Pearl Milkvine.

The flowers of Plateau Milkvine distinguish it
from Pearl Milkvine.

Queen

Growing up to 8 feet long, Bearded Swallow-wort, also called Thicket Threadvine and Aphid Vine, is a delicate vine that climbs on shrubs and small trees in open woodlands, in thickets, and along roadsides and fencerows in the Edwards Plateau and South Texas. It has small glossy lance-shaped, opposite leaves to 2 inches long, and from March to August, tiny creamy-white flowers appear in loose clusters from the leaf axils.  These flowers are 0.25 inches wide, bell-shaped, and have five distinctively hairy or ‘bearded’ recurved petals.  Five similar species in this genus are present in Texas, but this is the only one with ‘bearded’ flower petals.  Aphids are often found on this plant, giving rise to one of its other common names, and it is the host plant for the Obscure Sphinx Moth (Erinnyis obscura).

Bearded Swallow-wort is a rather delicate climbing vine.

The fringed or 'bearded' flowers
of Bearded Swallow-wort.

Obscure Sphinx

Whether it is due to their scarcity or diminutive stature, it is easy to miss these vines.  While they might be undervalued by humans, they are quite valuable to our native wildlife!