SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bd94a30cbda177457cf823203f759b34153bd184b484ae1602823b40ed0f217' 
  AND token = 'XuW4YHTRN6g/WEGH153H9zAb89vRNo+/qvPFjnlZBjU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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