SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '13fc8d20fff8be481630fcf9894ff75852a91d5cb0694323050cae37dfbb4005' 
  AND token = 'PRyMB+EzDP+/XzocL1frLfUIU/PZUAuXLS2guhKGCMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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