SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ed7a007c5084044e74fbaa3553b52f0312a622f72a74fae0f45bafb33206d05' 
  AND token = 'AP6+PQcUEpqsnNlk90BmRGvZ8IIIwp/YmRvZkxTFHag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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