Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6459974b844c2018455ef0366d8c3045788dfdfccfe70695135a4785b96de8a' 
  AND token = 'RMaISyX+UbqegAOkLNcfBE67rw9cmZz4kjqhnyWXlZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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