SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dc5ac7e275e368b6e9b420d469be94a346c5c98a079dea4c9dca6bea8afc4449' 
  AND token = 'klV9VUFPJX7u6ch69KNZrpq3WDBm2HCviGV3vEi2fJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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