SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '994cab478504283fb9deb6361476d89c24aa00ff0f6bd9544f96717ad0c160fe' 
  AND token = 'wKxUpfr2YJytxU0FsP/B9pQJV7SZHIXZDFzF0H6xcuA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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