SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae06985b7253cd24db1d8ba3fccc451bd2639b9acb3a9ddd4c7fc5efa4b01cb3' 
  AND token = 'MpIXzItBI7LPftRiDqbcP4rY8kTZVbS7b/rvQS4fhZ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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