SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1457505eb9d74da0c0df03782f5aaf6c204c324dfa0e8eba2ed08c80fa36c595' 
  AND token = 'ydlxJk1DMqfYMdCnFer+XfEOmqNOAxLR8yDvdOHLb40=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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