Compared to the twin-spotted spiketail, the arrowhead spiketail's yellow markings are larger and paler. The dorsal arrowhead markings on the slender abdomen are easy to notice. The male's abdomen is slightly clubbed while the female ovipositor (appendages at end of the abdomen) extends the length of a segment beyond the abdomen. The length of the body varies from 2.8 to 3.2 inches. The eyes are green. The female is similar in appearance to the male.
This species is commonly found throughout eastern United States and some parts of Canada. It is usually found at forest rivulets that are spring-fed and have a muck bottom, sometimes with rocks or in small rapid streams. It is infrequently found at scattered locations throughout Wisconsin.
Mid-June to late July in Wisconsin.