SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '39f5d02b65ade88811c94859c4a0bc930aa60499b7de4b85f52414199edff0c7' 
  AND token = '3inOlgz2+X83NhWtjNvNCmtewos/hugUUdS0M2/BjLM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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