Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df56ad9d412f7b9be1ba4bc2d35cfccf3e89750402a43b997f6dd9abff2b1b10' 
  AND token = 'CDi0CrGiTza52lxpIpLBn/wo1CywBQibCRT2PfTwyLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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