SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31f9609818d538417e1220e0cbf4f54cc8fcc5246f52418b2b65723053ff7782' 
  AND token = 'Hm69Kt8xuH4zVWyGxiaMZ+zwe/TL0I8WzriuWmiM4/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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