SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8c02473b56298d3db863055a3c23c5d0a9e17d776bfc341617700988dbba181f' 
  AND token = 'EqhSiA3XOWfhxKQyZxly7TGRAtewJjjBMXiBEvF1AnM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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