SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '80bec12a2ff1b5486ca79dd8326b883cea1ae12a9b8125b553ca7a985c26cace' 
  AND token = 'bcQ1GdHqufLTkag/YrxZ7bdjjnK1qhOKIQ6ogth5HPg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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