SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a63411669f2a3ccad9bf1383c7d4ec570f93280fb53faa4e4704b2ea9bdd9dde' 
  AND token = 'FaQyvZ/53sSos4PoYi+uXuxVOIlfBUNqg1WeDWKxTCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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