SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcfbdb04b008eaaed299d7ce21af7c8b93eb5b848a78eb855ac5af6cb91ff61f' 
  AND token = 'nLa5SeeXya8QpbKt9eEHKxuMi3Klxu0EEyzzd1CWxnY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}