# Arachnis (plant)

The genus Arachnis, abbreviated as Arach in horticultural trade, (common name scorpion orchid,) is a member of the orchid family (Orchidaceae), consisting of more than 20 species native to China, India, Southeast Asia, Indonesia, the Philippines, New Guinea, and the Solomon Islands.

## Description
### Vegetative characteristics

The appearance of the monopodial, epiphytic herbs of the genus Arachnis is characterized by distichously arranged, linear leaves. The vining plants may grow into a dense thicket. Arachnis does not produce pseudobulbs.

### Generative characteristics

The flowers are thought to resemble spiders, and they are fragrant. The fragrance has been described as musky.
* Arachnis labrosa growing epiphytically on a tree
* Detail of Arachnis labrosa flower
* Botanical illustration of Arachnis clarkei
* Detail of Arachnis cathcartii flower
* Detail of Arachnis flos-aeris flower
* Botanical illustration of Arachnis annamensis

## Etymology

The generic epithet Arachnis is derived from the Greek word arachne for spider.

## Ecology
### Habitat

Arachnis senapatiana has been found growing in subtropical broad-leaved forests at elevations of 1747 m above sea level.

### Flowering

Arachnis senapatiana is known to flower in June.

## Taxonomy
### Accepted species

There are currently 16 accepted species, including one natural hybrid:
* Arachnis annamensis (Rolfe) J.J.Sm.
* Arachnis bella (Rchb.f.) J.J.Sm.
* Arachnis bouffordii Ormerod
* Arachnis calcarata Holttum
* Arachnis cathcartii (Lindl.) J.J.Sm.
* Arachnis clarkei (Rchb.f.) J.J.Sm.
* Arachnis flos-aeris (L.) Rchb.f.
* Arachnis grandisepala J.J.Wood
* Arachnis hookeriana (Rchb.f.) Rchb.f.
* Arachnis labrosa (Lindl. & Paxton) Rchb.f.
* Arachnis limax Seidenf.
* Arachnis longisepala (J.J.Wood) Shim & A.Lamb
* Arachnis × maingayi (Hook.f.) Schltr.
* Arachnis senapatiana (Phukan & A.A.Mao) Kocyan & Schuit.
* Arachnis seramensis (Ormerod) R.Rice
* Arachnis siamensis (Schltr.) Tang & F.T.Wang
* Arachnis sulingi (Blume) Rchb.f.

### Species formerly placed in Arachnis

* Arachnis beccarii Rchb.f. is now considered to be Dimorphorchis beccarii (Rchb.f.) Kocyan & Schuit.
* Arachnis breviscapa (J.J.Sm.) J.J.Sm. is now considered to be Dimorphorchis breviscapa (J.J.Sm.) Kocyan & Schuit.
* Arachnis celebica (Schltr.) J.J.Sm. is now considered to be Dimorphorchis celebica (Schltr.) Ormerod
* Arachnis imthurnii (Rolfe) L.O.Williams is now considered to be Dimorphorchis beccarii var. imthurnii (Rolfe) Kocyan & Schuit.
* Arachnis longicaulis (Schltr.) L.O.Williams is now considered to be Dimorphorchis breviscapa (J.J.Sm.) Kocyan & Schuit.
* Arachnis lowii (Lindl.) Rchb.f. is now considered to be Dimorphorchis lowii (Lindl.) Rolfe
* Arachnis lyonii Ames is now considered to be Dimorphorchis lyonii (Ames) Ormerod
* Arachnis muelleri (Kraenzl.) J.J.Sm. is now considered to be Dimorphorchis beccarii var. beccarii
* Arachnis philippinensis (Lindl.) Ames is now considered to be Trichoglottis philippinensis Lindl.
* Arachnis rohaniana (Rchb.f.) Rchb.f. is now considered to be Dimorphorchis rohaniana (Rchb.f.) P.J.Cribb
* Arachnis beccarii var. imthurnii (Rolfe) K.W.Tan is now considered to be Dimorphorchis beccarii var. imthurnii (Rolfe) Kocyan & Schuit.
* Arachnis longicaulis f. flavescens Valmayor & D.Tiu is now considered to be Dimorphorchis breviscapa (J.J.Sm.) Kocyan & Schuit.

## Conservation

Arachnis has become extinct in Nansei-shoto.

## Horticulture

It can be cultivated under warm and moist conditions growing in pots, baskets, or mounted on slabs.