diff --git a/Project.toml b/Project.toml
index 49d8e90..fc3dfd5 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "DiffRules"
 uuid = "b552c78f-8df3-52c6-915a-8e097449b14b"
-version = "1.7.0"
+version = "1.8.0"
 
 [deps]
 LogExpFunctions = "2ab3a3ac-af41-5b50-aa03-7779005ae688"
@@ -11,7 +11,7 @@ SpecialFunctions = "276daf66-3868-5448-9aa4-cd146d93841b"
 [compat]
 LogExpFunctions = "0.3.2"
 NaNMath = "0.3"
-SpecialFunctions = "0.8, 0.9, 0.10, 1.0, 2"
+SpecialFunctions = "0.10, 1.0, 2"
 julia = "1.3"
 
 [extras]
diff --git a/src/rules.jl b/src/rules.jl
index c6f8e48..9ed53ec 100644
--- a/src/rules.jl
+++ b/src/rules.jl
@@ -121,6 +121,8 @@ _abs_deriv(x) = signbit(x) ? -one(x) : one(x)
 @define_diffrule SpecialFunctions.erfi(x)        = :(  (2 / sqrt(π)) * exp($x * $x)        )
 @define_diffrule SpecialFunctions.erfcx(x)       =
     :(  (2 * $x * SpecialFunctions.erfcx($x)) - (2 / sqrt(π))  )
+@define_diffrule SpecialFunctions.logerfcx(x) =
+    :(  2 * ($x - inv(SpecialFunctions.erfcx($x) * sqrt(π)))  )
 @define_diffrule SpecialFunctions.dawson(x)      =
     :(  1 - (2 * $x * SpecialFunctions.dawson($x))  )
 @define_diffrule SpecialFunctions.digamma(x) =