SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daf5b2f47eb34e4e296496cb416d7471709a66973c9551339f6c04fcde986c84' 
  AND token = 'ehZ424EwGHrTor79XyCWjLiLkUmWWOG+LOaEEkFO+88=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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