SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '83e5ee0ce82926b6152c167984125350f7b3093d652cd2f15eeafa842a639b8f' 
  AND token = 'qae4KpFQzVEF1Wm4ouQG5AqSKgXq7bd4KQ0mhD08APA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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