SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3e7a28d3d361959c431447d10fc7a52786b997a857340d2f11d6b60df230442c' 
  AND token = '0K9DCBhAD4sdOJZYFr7oeYCpCMkbQy0/uMNzd2rKLOU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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