SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c9c9b698968b30497aea94aa6868b0192d47ed9ab3ffa08069ea148e6a13895' 
  AND token = 'Bce/SAIZ/hJw7UUUFbaqbO0KCly7YgKkyhQhnTAihJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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