SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '191e657bbc4c06ddb99ba7200a283c6a93f58803eef46c6248a5faa4e81007ad' 
  AND token = 'A019S++/LWRpirS/PgLzLhUm7eh0loNyXoOYND47cVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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