SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'baa9ccfe51350b95f48af482ae3dc63fb28de8ce5d25cd3d06406c2cc6a0a19f' 
  AND token = '5jnyiokZAlxQhBbdQoRzPjXW7MOUf+rcJixQY6NVO5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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