SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f17f0137b46cf1a5925c6f2fcdea1e183e2d33be6dc56c34e59775fbe2b216e4' 
  AND token = 'VlRpK0zmeIvXHR1fIIaLeR3ir57iQj1zbxgccbkjfTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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