SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1352cfcb372cd54947c296aefaa60d83d999aa791c46a0f8de7eeef482f39c2' 
  AND token = 'p8hxPU9UXmKl/km+spaNJ05ijMvK7kUyjMUqoQrfnAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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