SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0dc8ec899bdef565d0b2eb3277a978076bdcb8a994c7a6c533491b5abf0d775' 
  AND token = 'Um+jO2p+YvtmjviPspWXhSLg/jcjWUOSVRs0dCKnz2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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