SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f00814e6234faf91246daaa05f60758e32c81826bd1ab2acad566f67f777799' 
  AND token = 'YsGVh68ggx/hJpK9EA4CS2spveNRqqnJMiwV9arzon0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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