SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7dbc9fd579fb3c9bd6c805b47933ad9e4ce6d59f11359a0159cef5f976cf3ceb' 
  AND token = 'EYcgFtWhmSFllt26qoeF5KEx35UUkTr97ji0bHflDWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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