SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '441d124bce5c4c90fd4503a04561bebd1f4f25da9670e97128693d2094cd0fa4' 
  AND token = 'XmeKPP2VdZPZ9ajoiKNjlJJ1uvc9FJQ0kEirIk7nwVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}