General description: Astragalus piscator is a short-lived perennial, with 4-10 lavender or pale lilac flowers on leafless, or mostly leafless stems. Stems are erect when in flower, and often spread out at the base of the leaves when in fruit. The foliage is covered with appressed, dolabriform hairs and is yellowish-green on top and gray-green below. Leaves are pinnately compound with 5-11 leaflets. Pods are somewhat laterally compressed and densely strigose (Spackman et al. 1997, Ackerfield 2015).

Look Alikes: Astragalus musiniensis is similar in appearance but has dorsiventrally compressed pods. Astragalus chamaeleuce also has similar pods but they lack the prominent dorsal structure and elliptic cross section of A. piscator (Spackman et al. 1997). Astragalus piscator is related to A. chamaeleuce, A. musiniensis, and A. amphioxis. It differs from the first two in having chartaceous, not alveolate-pithy pod walls, and differs from the third in flower color which is pale lilac as opposed to vivid pink. The habit and shape of its leaflets suggests A. musiniensis (Cronquist 1989). 

Phenology: Flowers late April to early June (Colorado Natural Heritage Program 2012, Ackerfield 2015).

In Colorado, Astragalus piscator appears to be associated with the Cutler Formation (Colorado Natural Heritage Program 2015), in sandy, sometimes gypsiferous soils of valley benches and gullied foothills (Spackman et al. 1997).  Associated plant community: Juniperus osteosperma. Additional associated plant species: Artemisia tridentata,Coleogyne ramosissima, Atriplex canescens, A. confertifolia, A. gardneri, Sarcobatus vermiculatus, Penstemon utahensis, Castilleja chromosa, C. scabrida, Physaria acutifolia, Cymopteris fendleri, Lepidium lasiocarpum,  Arabis pulchra, Cryptantha gracilis,  Bouteloua gracilis, Allium macropetalum, Erioneuron pulchellum, Townsendia incana, Oryzopsis hymenoides, Chrysothamnus viscidiflorus, Eriogonum inflatum, Astragalus lentiginosus, Oxytropis sericea, Astragalus flexuosus, Stephanomeria tenuifolia, Eriogonum corymbosum, Haplopappus nuttallii, Cryptantha fulvocanescens, Lepidium lasiocarpum, Cymopterus acaulis, Androstephium breviflorum, Townsendia incana, and Astragalus lonchocarpus. 

Elevation Range: 4,511 - 5,581 feet (1,375 - 1,701 meters)

Colorado endemic: No
Global range: Occurs in Arizona, Utah (San Juan, Grand, and Wayne counties), and Colorado (Mesa County).
State range: Known from four occurrences in Mesa County in Colorado. Also known from Utah.

The primary threat at this time is considered to be roads (Rondeau et al. 2011). The Colorado occurrences are partially within the BLM Palisade Wilderness Study Area, and the Palisade Area of Critical Environmental Concern (ACEC). However, the area is heavily grazed and includes many exotic species (e.g., cheatgrass and Russian knapweed). A portion of this occurrence is also near the Gateway Community Center. Motorized recreation poses a threat at this location.