SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a69f67de9bc6efdc90ea82b2e921ab43f530639ccb97f12509ff645b04dec100' 
  AND token = 'bk4BvVK/x4uPw1un6FH4SKzCbhKIzJMhoeLb4KlQdpk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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