Journal Number 104
August 2007

THE COLUMN

Mike Lusk's North Island Orchid SUPs
By Eric Scanlen

New member, Mike Lusk first tantalised the Editor and the Column with a photo of Thelymitra hatchii (photo right) from near Kiwi Saddle, ER 27, in this Kawekas' SUP (site unreported previously).

Mike then scored a hit to the Column, with a CD of Caladenia inhabiting the eastern ranges from Kiwi Saddle to Haurangi State Forest east of Wellington as you can read below.

But, T hatchii has the flower inverted and it has stayed open through a cloudburst as evidenced by the water surrounding the column. Mike is glad he photographed it then, under an umbrella because in later visits it was never properly open again.

Sun orchids are supposed to close in bad weather to protect their column organs from the wet but it seems they occasionally slip up. You may notice that this specimen differs in detail from others under the classification umbrella of T. hatchii. This is an amphidiploid hybrid of T formosa and T longifolia according to Brian Molloy and Murray Dawson so one can expect variations of both parents to be reflected in the progeny.

A second email of Mike's showed a Caladenia minor (chlorostyla) from the Kawekas in late Feb. 2007, showing a good top flower with typical toothed midlobe and green dorsal sepal but the lower flower is a gross mutation, with a vestigial labellum split in two and the two lateral sepals united as one, quite symmetrical but wider than normal. ER27 is also a SUP for C. minor.

February is very late for C. minor, reminiscent of Tricia Aspin's late, one-to-four flowered colony from the Awhitu Peninsula. [J103:12]. Such late flowering and multiple flower heads could well be worth investigating further.

From Mike's CD, and near Kiwi Saddle, was C. variegata, Fig.15, another SUP. Notice the pink tepals and the typical extra or stray disc calli as originally described by William Colenso.

Mike belongs to Heretaunga Tramping Club and had arrived at Kiwi Saddle check point in the Kaweka Challenge mountain race, a day early to test his suggestion to DoC that volunteers could pull seedling Pinus contorta rather than let them mature to chainsaw size. Good thinking! During this worthy test, orchids just happened to show up, of course, so demanded attention.

Thirty years ago, the Column and party were pulling P. contorta around Ruapehu and had vaguely
hoped it would be under control by now. Not so, this weed pine is still threatening to take over the
tops of our southern N.I. ranges to the exclusion of native subalpine and alpine plants. It has been
whispered around that Kyoto protocol people have conspired to plant them to improve NZ's carbon
credits would you believe? Where were we?

Down in the Ruahine's, near Triplex Hut, ER 33, Mike spotted a Caladenia minor Fig.16, another SUP. The orchid has unusual, tilted out labellum wings and midlobe teeth not showing at all well in this view, if they exist. Its curled down dorsal sepal is typical of over mature Caladenia which might or might not explain its other unusual features.

Fig. 15. Caladenia variegata from near Kiwi Saddle, site previously unreported. Note the extra disc calli typical of this species.		Fig. 16. Caladenia minor from near Triplex Hut in the Ruahine's, ER 33. Site previously unreported. Note the unusual turned out labellum wings and the dorsal sepal hooded over the column typical of over-mature Caladenia.

Further south, in the Haurangi State Forest, was C. aff. variegata in Fig.17, lacking the stray disc calli of Colenso's species. Notice the unique green labellum wings! These are supposed to be a dazzling white; green should be for the column wings!  

Also in Haurangi S.F., C. aff. pusilla, Fig.18, from a SUP and the southern most yet reported, being some 35km further south than the Editor's from Kaitoke. Notice the typical dark dorsal sepal clamped down on the column, the rounded sepals, three marginal calli to the midlobe base (standard but not illustrated in the Field Guide) and turned up petal tips.

Fig. 17. Caladenia aff. variegata (without the extra disc calli) with nonstandard green labellum wings from Haurangi State Forest.		Fig. 18. Caladenia aff. pusilla also from Haurangi S.F., the furthest south reported to date. Note the three marginal calli to the midlobe base, dark dorsal sepal hooded over the column and upturned petal tips all typical of this taxon.

For a new member, Mike has excelled himself more than he probably realises with a host of new sites and some variations on accepted taxa that definitely need further investigation.