SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6be7bd6f21cfe25c15fb97b321b19ac0cdb7ae7e805f6fdc56c027b45bf38989' 
  AND token = 'IzMBjwroK7k7QPGUuh2zVh/vjuq8qCxbA4wfIhIpA4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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