SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3b28bfb7ec95a12d4e236bdc3d18cf957ac896110d75ce62b5bbb0d61ddedb6' 
  AND token = 'iypQNomGpi9zsbY/oJcfYdMxzyOp7aJChuXC0WKlhss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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