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Archival [3.6] and [4.5] images are used to identify and characterizevariable stars in the Magellanic-type galaxies Holmberg II, NGC 2366, and IC2574. Using parametric and non-parametric detection methods, 74 confirmed orsuspected long period variables (LPVs) are found. The period distributions ofthe LPVs in NGC 2366 and IC 2574 are similar. While the period distribution ofLPVs in Ho II is uncertain due to small number statistics there appears to be adeficiency of LPVs with periods between 550 and 650 days when compared with NGC2366 and IC 2574. The LPVs are diffusely distributed on the sky, and do notfollow the underlying light from unresolved stars, as expected if episodes ofstar formation within the past few hundred Myr have occurred throughout thegalaxies, including their outer regions. Distances computed for Ho II and NGC2366 from the period-luminosity relations (PLRs) agree to within ~0.1magnitudes with those based on the tip of the red giant branch (RGB). Effortsto estimate an LPV-based distance modulus for IC 2574 are complicated by thepresence of first overtone pulsators among LPVs with periods ~ 600 days,although the PLR at the long period end is consistent with the distanceestimated from the RGB-tip. In addition to the LPVs, 10 candidate sgB[e] orluminous blue variables and 2 candidate red supergiant variables are alsoidentified. Nine candidate sgB[e] stars that do not show evidence ofvariability are also identified based on their locations in the color-magnitudediagram.

Red Variable Stars in Three M81 Group Dwarf Galaxies