SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d6395af8c98bd35e345603a8075504b5bdf3b9b1a680658ad393d261f57260c' 
  AND token = '1DFRIZqXOySIsPpZR2XIgjgT68Q/J/lF+lLaAVCMegs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}