Family Calopterygidae of Sabah

* endemic species that naturally occurs in only Borneo Island

♂♀


1   Genus : Vestalis Selys, 1853: (Vestinus) Kennedy, 1920
* 1 Vestalis amabilis Lieftinck, 1965
  2 Vestalis amaryllis Lieftinck, 1965
* 3 Vestalis amnicola Lieftinck, 1965
  4 Vestalis amoena (Hagen, 1853)
* 5 Vestalis anacolosa Lieftinck, 1965
* 6 Vestalis atropha Lieftinck, 1965
* 7

Vestalis beryllae Laidlaw, 1915

    Vestalis gracilis (Rambur 1842) Note: Not found in Borneo yet. Recorded in Peninsular Malaysia
    Vestalis amethystina Lieftinck, 1965 Not found in Borneo yet. Recorded in Peninsular Malaysia
    Echo modesta Laidlaw, 1902 Not found in Borneo yet. Recorded in Peninsular Malaysia
     

Vestalis gracilis  (Rambur 1842)

Vestalis amoena (Hagen, 1853)
Vestalis amethystina Lieftinck 1965

   
  V. amoena  (Hagen, 1853)

V. amethystina Lieftinck 1965

 
 
     

 


2   Genus : Neurobasis Selys, 1853
* 1  Neurobasis longipes Hagen, 1887
    Neurobasis chinensis (Linnaeus, 1758) Not found in Borneo yet. Recorded in Peninsular Malaysia

3   Genus : Matronoides Forster, 1897 (endemic genus of Borneo)
* 1  Matronoides cyaneipennis Forster, 1897

Calopterygidae, with over 160 species worldwide, is a widespread family best represented in the tropics. In Borneo there are nine species in three genera. One genus, Matronoides, and seven species are endemic. The family is best represented in north Borneo owing to extensive speciation there in the Vestalis amoena group.

All calopterygids are slender and fairly large (hw 30-40 mm) with long thin legs. In both sexes the head and body are mainly metallic- green. There is no pterostigma in any Bornean species (although it occurs in the south-east Asian genus Echo). The wings are densely reticulated with 22-70+ antenodal cross veins. Fore- and hind wings are nearly equal in length, broad and rounded, without a definite stalk.

Calopterygids typically occur in pristine habitats, especially small- to medium-sized clear forest streams, up to 1700 m. A few Vestalis species are common in swamp forest. The sexual behavior of many calopterygid species from temperate regions has been well studied, but Bornean species are less understood. However some form of courtship and mate guarding is common. Larvae are elongate with spidery legs and long narrow caudal lamellae, the middle one being shorter than the outer pair. They usually live in leaf packs or among stones on forest streams with clear fast flowing water.



Vestalis amoena occurs throughout lowland Borneo, up to about 500 m, and elsewhere in Sundaland. It is common on larger forest streams and is the most wide-spread of six very similar species, all with a metallic-green head, thorax and abdomen, and clear wings reflecting purplish or greenish iridescence from certain angles. As far as we know, in all species mating is preceded by courtship in which the male dances around the female displaying the sparkling colors of his wings. Females oviposit in dead leaves around the margins of streams, either guarded by the male or alone. The larvae of amoena are found among leaves and pebbles at the edge of fast flowing water. The other five species are distinguished from amoena and each other mainly by the form of the male appendages. They differ also in distribution and ecology.

 


 

Vestalis amaryllis

Vestalis amaryllis inhabits smaller, often sluggish forest streams throughout Sabah. This male one was found in Tawau Hills Park. There were several Vestalis amaryllis on that sunny morning.

 


Vestalis amabilis is found in lowland northern Sarawak and Brunei, on .clear forest streams bordered by Pinanga and Dipteris lobbiana and also in swamp forest with Pandanus. Both males and females are sometimes abundant along forest paths in low country where they perch on leaves, often rising to capture small insects. Vestalis amnicola is confined to small swift forest streams to about 800 m in north Borneo. It is very local but not rare where present.

Vestalis anacolosa is on average a little larger than the other species and is confined to small swift forest streams up to about 800 m in Sabah, including the Crocker Range, Kinabalu and the Danum Valley. In this species the inferior appendages are reduced to stumps which can easily be seen with a hand lens.

 


Vestalis atropha

Vestalis atropha is known only from the lowlands of northern Sarawak and Brunei where it occurs sporadically on small swift forest streams. It frequently perches on the leaves of low shrubs inside the forest. The inferior anal appendages of the male are withered and very thin.

 


Details on the separation of all the above species require examination with a stereo microscope for reliable identification. A detailed key was published by M.A. Lieftinck in 1965 (Tijdschrift voor Entomologie 108: 325-364.) which is available in most older university and museum libraries. Vestalis species in this group are among the commonest and most easily captured Odonata in many habitats.


Vestalis beryllae 4  is easily recognized by the very long abdomen of the male. The wings are longer and narrower than in other species. The female too, although less distinctive, is clearly different from other species in the genus in size, wing-shape and relative length of abdomen. It occurs throughout Borneo up to 1000 m, most frequently deep inside primary forest in steep country. It frequents sun patches, often far from water, but is never very abundant.

 


The brilliant Neurobasis longipes is surely one of the most spectacular species to witness in nature. The males flutter tirelessly up and down, over riffles and swift channels in broad, boulder-strewn forest streams. Sunlight flashes rhythmically from the iridescent green hind wings. Often they perch for long periods on fallen logs awaiting the arrival of females. The female too, is bright metallic-green on the body, but the wings are clear, tinted a light yellowish-brown. They are easy to separate from Vestalis species by their very long legs. Mating is preceded by a dainty fluttering courtship dance. The species occurs throughout Borneo but only from clear, swift streams in the lowlands. It is closely allied to jVestalis chinensis found in much of tropical Asia. There is some confusion concerning the status of longipes, some believing it to be a race of chinensis, but as both co-occur in Kelantan there is no doubt they are good species. The larvae are remarkably thin and elongate, considerably more so than those of Vestalis sp. They live among root masses or detritus in swiftly flowing water and emerge at night to feed.


Another splendid and unmistakable species is Matronoides cyaneipennis. It is the largest damselfly in Borneo (hw 3841 mm) and the broad wings of the males are entirely colored with deep metallic blue-green reflections. The body is dark, almost black, and the legs are exceedingly long. The female has clear, brownish tinted wings and a weakly metallic-green body. It occurs on streams in moss forest at 800-1700 m and is known only from Mount Kinabalu and mountains in northern Sarawak. Although it is a conspicuous insect, the shimmering metallic color of the male is not always obvious as it flutters in the shadows over little montane creeks. The life history is unknown.


INDEX : Damselfly     October 15, 2016 07:40:52 AM