SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '64873d3a2117cf09b319999e3d39ed77161636a29373022b1b230ba25b782ba1' 
  AND token = 'CAXGj755Zw+CBGbgtJx8G3KKQLuOaAsgT/EjzhR3JPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}