SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3faa346e513cc5adfaf7bd6ebbc2440a6e8329ac206d5f31fa39148bc2fbf897' 
  AND token = 'QNhKBs6tx9wk6qqXsR7eYTHZACY+zwn1Hghigwjje28=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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