SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d2cfe1e89597a3820cd7cfb09360cdaac786948604715d75d3161884752988d' 
  AND token = '4quuO/gITX/BYduM7h4C3mxe+26wJgq8yHKrpxVCu7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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