SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1392be8d438240ffb6ef0ba1a92a9c2331424668fe4764edbc4be76b859a7a35' 
  AND token = 'G/ZQRXtiSqWcnWrJ3aPGeFNZ0kJJ57s6YZxDlbfrsUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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