SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffda071fbc3b5b30e0c300d8175b1798c3e7777d4604821507703fd80bc7364f' 
  AND token = '0gD4dpNh9txgvGXpibXjlcopMMCNwN9k146JaOgVP/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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