SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54b8dca13133875d19ab0aa87c764f0287e17d949fff7030c9ced483bf311d7b' 
  AND token = 'qAGwg3YRQTc0r5jGcJPgxggGREf+9qzKGJZCdFZEXRA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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