Monday, 31 July 2017

Love is in the Air: Lovebugs

Almost every time we put out  light sheet in northern Australia, no matter where, in or around rainforests or out in the open country where mixed forests dominate, "Lovebugs" show up.


Plecia ornatipes 

Firstly, Lovebugs are not bugs at all. They are flies, relatively primitive flies in the family Bibionidae. There are about 30 species in Australia. The larvae live in the soil and are considered beneficial in that they help to decompose leaf litter and other organic material.

The flies usually arrive shortly after the lights are turned on. They arrive singly but it does not take long for males to find females and mating to occur. In this shot, the male is the top fly.

Males have a differently shaped head with large eyes that are only narrowly divided.
 Plecia ornatipes, male 
Plecia ornatipes, male showing large eyes



 Plecia ornatipes, female


Females have more prognathous, or projecting mouthparts, seemingly adapted for dipping deep in the floral parts of plants.

What do Lovebugs do, other than the obvious? Adults feed on flowers and probably are pollinators as they can live for about 3 days. Males seem to have reduced mouthparts and may not feed.

In Florida, an introduced species from South America, looking very much like P. ornaticeps, occurs in such number that flying swarms can obstruct windscreens at certain times of the year. 

Taxonomists usually rely on the structures of the males found at the tip of the abdomen to make their identifications.

Tip of the abdomen of male Plecia ornatipes

a braconid wasp at the same lightsheet as the Lovbebugs

This fly seems to be involved in a mimicry complex. Birds and lizards seem to avoid eating the adult flies. The flies usually spend the day on the light sheet, whereas, the moths, beetles and other insects that accumulate seem to be rapidly consumed by birds. Could the braconid wasp shown above be part of such a complex?

Sunday, 16 July 2017

Moth Night 2017

Well it was perfect weather in Cairns until a few days before the Moth Night, then it changed. Cool showers from the south dampened our night. There were 40+ people in attendance and even fewer moths!

This year we set up the light sheets in the Fitzalan Garden, just across the street from the Cairns Botanic Gardens Visitor Centre. It seemed like a good spot being adjacent to the Rainforest and the Boardwalk and  a few metres from a small pond.
Rain showers were intermittent but just enough to keep the insect numbers down. Peter Shanahan lead a few hardy souls down the boardwalk while others stuck it out at the lights.

We decided to try again after the new year, perhaps, at the Catanna Wetlands or the Crystal Cascades picnic area.

Here are a few shots taken by Buck Richardson of what did turn up.
 Amerila rubripes: Arctiidae
 Glyphodes canthusalis: Crambidae
 Manulea dorsalis: Arctiidae
 Thalassodes pilaria: Geometridae
Hyalobathra crenulata: Crambidae
I'm going back to bed!

Saturday, 8 July 2017

A Look At Some Local Mantids



Praying Mantises are among the most recognised of insects. They have the reputation of being "good guys" because they eat other insects and that makes them beneficial. A world catalogue of mantises (or mantids, if you prefer) can be found on the Mantis Species File: http://mantodea.speciesfile.org/HomePage/Mantodea/HomePage.aspx

Australia has a substantial diversity of mantids. They occur in most habitats and have varied life styles. Here in the rainforest we have a number of species that you don't see elsewhere--out in the open woodlands, for example. But many of them seem to occur in both habitats.
In the first instance below, the family, subfamily and tribe are listed just to show the diversity in just the few species noted.
The delicate Neomantis australis Sasuure and Zehntner; Iridopterygidae; Tropidomantinae; Tropidomantini  spends its life on and under leaf surfaces where it hunts for small insects. It seldom strays from rainforest habitats.

 Calofulcinia oxynota LaGreca: Iridopterygidae; Neomantinae; Fulcini is a tree running mantis. It spends most of its time hunting on tree trunks. It has also been found on large moss-covered rocks. Its colour and pattern camouflages it quite well under such conditions.
Metoxypilus costalis Westwood: Amorphoscelidae; Paraoxypilinae; Paraoxypilini is an infrequent visitor to lights in Kuranda. It may be associated with termite mounds.
Kongobatha diademata Hebard; Iridopterygidae; Tropidomantinae; Tropidomantini  is a fast-moving little mantis that lives in both the rainforest habitat but can also be found on shrubbery in open woodland habitats where it can be quite dry. 

 Kongobatha diademata Hebard
The little Garden Mantis, Orthodera ministralis Fabricius; Mantidae; Orthoderinae is quite common across much of Australia. But probably when it is studied thoroughly, a number of distinct species will be unmasked. This mantis comes to lights in the rainforest as well as in some of the driest places in the tropics.
This nymph of the Garden mantis may turn green on its last moult. Here it waits in ambush on a dry grass stem at night in the mixed woodland not far from Kuranda.

Taxonomists use a wide variety of characters in determining mantis species. This Garden Mantid provides an example.
The inner surface of the left foreleg carries a number of distinctive characters. The pattern of spination is important in placing the mantid to family. Since mantids are highly visually-oriented in their behaviour, the colour and patterns on the inside of the forelegs are used in recognition. The colour and pattern seems species-specific and provide useful characters for people studying mantises at the species level.
This is the left foreleg, inner view, of the large Hierodula majuscula Tindale; Mantidae; Mantinae; Paramantini. Compare the photo with the above and you can see many differences in spination pattern and colour.
The head also has many characters useful to the taxonomist. Compare this head with the one at the top of the blog. The the ocelli on the top of the head are in different positions and they seem proportionally larger in the top mantis. Also not the difference in the colour and pattern of the segmented mouthparts.

Male Ciulfina rentzi, note the genitalia at the tip of the abdomen.

Taxonomists rely on features of the genitalia almost as a final assessment of the identity of a species. This works in most groups but not all. In fact, a professor of mine once said that all a taxonomist needs is a locality label and the male genitalia to identify a species. That is ridiculous, of course, but there is some truth in it.

Recently our colleague, Ms Sydney K Brannoch gained some notoriety, especially in feminist circles, when she described a mantis species based on a female and female internal characteristics. She named it in honour of one of her "heros" US Supreme Court Justice Ruth Bader Ginsburg. You can see her interview on the subject: https://www.cmnh.org/science-news/announcements/ilomantis-ginsburgae. The point of the study was to illustrate that there are important characters distinctive in females as well as males. This has been shown in other groups as well. Grasshoppers are a good example.

A few more examples of local mantises
Hierodula majuscula, one of the two large mantids that comes to lights in the rainforest. This species seems to come in late summer but individuals can be found throughout the year. It is big enough to subdue a small lizard or frog if it has the opportunity.
Tenodera australasiae Leach: Mantidae; Mantinae; Polyspilotini is more common in open woodlands but it comes to lights in the rainforest from time to time. It is certainly the longest mantis in this area.
Sphodropoda tristis Saussure: Mantidae; Miomantinae; Miomantini is a colourful, large and aggressive species that occurs inland, well away from rainforests.

 Nymph Ciulfina rentzi,
 Male Ciulfina rentzi,
Ciulfina rentzi Howell, Ginn, Herberstein; Liturgusidae; Liturgusinae; Liturgusini is a diurnal mantis that is usually called a "tree runner" because it is mostly found on tree trunks where it hunts small insects. However, after dark the mantises move off their trunks onto adjacent vegetation to seek new sites. We make this observation repeatedly.

The type locality of this species, the place from which it was described, is the Cairns Botanic Gardens, Cairns!

The Wrong Place At The Wrong Time

Here we have a female Migratory Locust, Locusta migratoria Linnaeus, in a most unfortunate circumstance.
Migratory Locust, Locusta migratoria Linnaeus, female

Migratory Locusts fly at night, often great distances. Their movements have been tracked in the past by the Plague Locust Commission, http://www.agriculture.gov.au/pests-diseases-weeds/locusts/role. The Plague Locusts are often distracted in their nocturnal movements by strong lights. Petrol Stations, cafés, shopping centres often have numbers of these and other grasshoppers and locusts around their lights. During plagues, the numbers can be considerable and attract public concern.

We had our night lights in operation the other night near Koah, Queensland and this female dropped in. She settled down in precisely the wrong place. She was set upon by a Badge Spider, Heteropodidae, probably Neoparassus sp.
The spider will spend several hours sucking and masticating the locust until it is satisfied.

Tuesday, 4 July 2017

An Unexpected Visitor

Ozphyllum kuranda Rentz, Su, Ueshima, adult female

It is the beginning of "winter" (the dry season!) here in the Australian tropics. Most of the summer, or wet season species, seem to have gone to their reward so it was a surprise when this female katydid showed up at the light a few weeks ago. I would have thought her time was well and truly up weeks ago.
Ozphyllum was described to include two species, this one from the coastal Queensland rainforest from about Bundaberg to Cairns but not including the Atherton Tableland. The other, O. naskrecki Rentz, Su, Ueshima, occurs along the coast from just north of Brisbane south to just north of Coff's Harbour, New South Wales.

Ozphyllum seems to be most closely related to Cosmophyllum from Chile. This deduction needs further confirmation as it could just be a matter of convergence. The katydids appear to be quite clumsy and prefer to hop to escape danger rather than to fly. Ozphyllum is unique in the Australian katydid fauna in that no other genus looks at all like it. Males sing in late afternoon from perches in understorey shrubs. 

No end to the surprising Australian insect fauna. 
 Ozphyllum kuranda Rentz, Su, Ueshima, adult female
                                        Ozphyllum kuranda Rentz, Su, Ueshima, adult female

To see a male, go to:
http://bunyipco.blogspot.com.au/search?q=Ozphyllum

Literature
Rentz, DCF, Su, YN, Ueshima, N. 2007. Studies in Australian Tettigoniidae: Ozphyllum, a new genus of Phaneropterine katydids with comments on its relationships and ecology. (Orthoptera: Tettigoniidae; Phaneropterinae). Zootaxa, 1629: 57-68.