SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a603e50b6f4dc53d938978874078ec2b04a27f112a5b5b6a0dc788ad8f8acd4f' 
  AND token = '6FpeycltYOEZ4FHhnocLIihqqTl0jTzGDg2JRix2qxw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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