SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4759d0054c73f7207d7c7b63272337a9bf9587d3b74afac992311b57146f9617' 
  AND token = 'zndOf+jYJFMi9zrWuQQzgp316tZWRD0iYvW14YMVRrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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