SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92a6ea912ad0ae32b5e4bc11f81f93839cb2d78185bc12e304c5de037f4365ec' 
  AND token = 'VuMZtxccyuB0QS+qhT4LT4jo5KFCsEwuu13dLfvdACI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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