SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbae876c287b2c80d2351523ab4daedeb83bf79efb8b307e8456e4178d2ae4fe' 
  AND token = 'GvUm4I+SkvFgLjBuav+ffdaqVvdCSIumYHmNK8eVQjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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