SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '606ab83a2ad4893abe899b810f464f3d5907fa70af3685dcf1724ec6f8851be6' 
  AND token = 'ICrYugYw4MXHJlm0rQF5H0kKmLhlu7e9hiGZYYsu2NA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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