SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '33a84dbac3e84770f8948be8956b8b0273f6cc683c4cc1db2d1d9b924d3743ad' 
  AND token = '0whPcz3ZttmISkwl+W0vVJ880WBdTx/EvXipzYNl2AQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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