diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 4c860cc..c4989a9 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -55,22 +55,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        go: [1.13, 1.23]
+        go: [1.16, 1.23]
         os: [ubuntu-latest, macos-latest, windows-latest]
-        include:
-          # TODO(panjf2000): There is an uncanny issue arising when downloading
-          # go modules on macOS 13 for Go1.13. So we use macOS 12 for now,
-          # but try to figure it out and use macOS once it's resolved.
-          # https://github.com/panjf2000/ants/actions/runs/9546726268/job/26310385582
-          - go: 1.13
-            os: macos-12
-        exclude:
-          # Starting macOS 14 GitHub Actions runners are arm-based,
-          # but Go didn't support arm64 until 1.16. Thus, we must
-          # replace the macOS 14 runner with macOS 12 runner for Go 1.13.
-          # Ref: https://github.com/actions/runner-images/issues/9741
-          - go: 1.13
-            os: macos-latest
     name: Go ${{ matrix.go }} @ ${{ matrix.os }}
     runs-on: ${{ matrix.os}}
     steps:
diff --git a/ants.go b/ants.go
index 4b61ba2..dd170a6 100644
--- a/ants.go
+++ b/ants.go
@@ -88,9 +88,7 @@ var (
 		return 1
 	}()
 
-	// log.Lmsgprefix is not available in go1.13, just make an identical value for it.
-	logLmsgprefix = 64
-	defaultLogger = Logger(log.New(os.Stderr, "[ants]: ", log.LstdFlags|logLmsgprefix|log.Lmicroseconds))
+	defaultLogger = Logger(log.New(os.Stderr, "[ants]: ", log.LstdFlags|log.Lmsgprefix|log.Lmicroseconds))
 
 	// Init an instance pool when importing ants.
 	defaultAntsPool, _ = NewPool(DefaultAntsPoolSize)
diff --git a/go.mod b/go.mod
index af3906b..2e75d8f 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/panjf2000/ants/v2
 
-go 1.13
+go 1.16
 
 require (
 	github.com/stretchr/testify v1.8.2