SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '635f893d8660d806cb1fdf2459541490c3398c1528be64f49b670bf3e49e0ed5' 
  AND token = 'G0lPUhWWwB9WA/qXYVcVncn9aQMDfj6+8Vi7f/R7//E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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