SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba02dad61129c36e1239dd1b16feb607fb4e2f2c2bfbd7043b000ad0a8063ae9' 
  AND token = 'bb/lu06Ui7QguWc8YhjBKNQ0Mc2rCqOdOEwURVc0AJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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