SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3987075056fd3f888fe4dc930749e73c21fdd38879f4ba7cc865cf2a7024922' 
  AND token = 'exXVovWDdFNJuxQ1zLRV6Z2TYDWRcAU8X9DBYuiGY3E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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