SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '605000061ed3077ae8ff5bb872832e108b649b8a3c827e71022abc9e2bec7fdf' 
  AND token = '7upsrt62AG1eEDECDPEKKDUelmR5o+HC1bvTiGt5iXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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