SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9b734247b2b36771e3d1f27bab6e93b6569c8341dcc66f51ff4b356698c8744a' 
  AND token = 'c+LQbGJVx9KyC8KjXWNRVe8z8YZZhFxPZrGWDGx8gXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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