SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '805ebcfad3cfc08c29edc551e91da35e41514c6b08c0bab54f1f325364e6e8d3' 
  AND token = 'oMg6tveEowRF0AC7Dy83M8BmPz3CTieJ4nzzKmz5Jpc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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