SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '984df2ff16c427d2984b05f702db9aaa324352ba41901d4cdf27fbc67a741048' 
  AND token = 'asgkOq1I15zCWUKGARFSQtX61C9jgnYJGVxD1XZd5Zc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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