Saturday, 3 December 2016

The Thick-Headed Flies - Conopidae

A rather larger - and much more confusing - family than last month's Micropezids, meet the Thick Headed Flies:
Conops (unidentified species) in Chongwe District, Lusaka, Zambia; February 2013.

These colourful, wasp-like flies have had a tumultous taxonomic history; bouncing between the Aschiza (along with Hoverflies such as Metadon inermis) and the Schizophora (along with the greatest diversity of modern flies, including such oddities as the Stalk-Eyed Diasemopsis meigenii), but while genetics support its relationship to the Schizophora, its position therein remains imperfectly resolved (Gibson et al, 2010); but the family itself has been quite intensely studied (e.g. Gibson and Skevington, 2013).
Sicus ferrugineus Scopoli, 1763,
in Chichester, West Sussex, UK; July 2013.

Their life-habits are fairly remarkable, too; while adults are often found visiting flowers, they spend their larval stages eating other insects - usually bees (as is the case with Sicus ferrugineus Scopoli,1763 from the UK) or wasps of various families; a few species are known to parasitize cockroaches and crickets.

Wasps and bees are by no means an easy target for a fly with a limited physical arsenal; no powerful sting, no heavily-built, piercing mouthparts (which would be somewhat counterproductive, at any rate); and so many get around this problem by looking remarkably wasp-like:

Archiconops pseudoerythrocephalus Stuke, 2004 on banks of Luangwa; Eastern Province, Zambia, April 2015. 

Unidentified Mammoth Wasp (Scoliidae) from Lusaka,
showing similarity of appearance to that of Archiconops
The above Archiconops was closely following a Mammoth-Wasp (family Scoliidae), which itself was probably an external parasitoid of larval Scarab beetles; although Scoliids - unlike may parasitoid wasps - can sting, Archiconops is likely given some protection by its resemblance, allowing it to get close enough to use its scimilar-like ovipositor to rapidly lay an egg between the wasp's thorax and abdomen, and its agility - much greater than the often-bumbling Scoliids - allows it to beat a hasty retreat as soon as the wasp catches on.

 But there are other risks to hyperparasitism; evolutionary risks. While the wasp's populations are at the mercy of fluctuations in beetle populations, and must remain at a relatively low level to ensure that they do not begin to exhaust their host populations, the fly's survival depends both on the wasp and on the beetle, and if either of them has a bad year, the fly's population will plummet - and with reproductive rates necessarily low to avoid causing a crash in host populations, they can take generations to recover, and are rarely - if ever - common.

Conops cf aurantius Brunetti, 1925 in garden in Chongwe, Lusaka, Zambia;
only a handful of these flies will be seen per year even in most rural environments. 

Identification can also prove surprisingly complicated; although the flies are very distinctive as far as flies go - even if they may, at a glance, they may be mistaken for the wasps they mimic - there are a precious few others that can be strikingly similar.

Systropus Weidemann, 1820, is a wasp-mimicking bee-fly (family Bombyliidae)
that can bear a striking resemblance to some Conopids. Chongwe, February 2016. 

Physocephala rufipes (Fabricius, 1781)
in Bosham, West Sussex, UK

The fly immediately above is a Zambian example of Systropus Weidemann 1820, an unusual genus of Bee-flies (Bombyliidae) which, like most Conopids, closely mimics wasps. Physocephala - a very widespread genus of Conopid that also occurs in the region  (although the species shown is the British Physocephala rufipes (Fabricius, 1781)) - can be very similar; and they are probably most easily distinguished by their eyes; in Conopids, these are always widely separated, while in Systropus, they meet at the top of the head.

There are numerous other distinctions, particularly in the dramatic external genitalia of many female Conopids; but the widely separated eyes are a very prominent feature of the Conopids, and help to mark out this (un-cooperative) Conops cf elegans Meigen, 1824 as a member of the family [NB - various flies in various families ALSO have widely separated eyes, but are not nearly so Conopid-looking as Systropus].

Conops cf elegans, Meigen 1824.
Banks of the Luangwa River, Eastern Province, Zambia, April 2015.  

And just to be going with, the European Conops quadrifasciatus De Geer,1776 in a West-Sussex Garden. Although this species was only formally described some 18 years after Linnaeus' Systema Naturae transformed entomology in 1758, the genus - which we have encountered almost throughout this post - is actually one of the first described of all invertebrate genera*, as one of only 10 genera of flies that Linnaeus actually described.

Conops quadrifasciatus De Geer,1776 in Bosham, West Sussex, UK; August 2013.

More details about Conopid life-histories can be read in Gibson's 2011 thesis on the family, which is (unlike the other two Gibson papers) freely available online. 

A good starting place for Conopids in Southern Africa is O. Kröber's The Conopidae of South Africa, in Volume 14 Annals of the Transvaal Museum; this is a very elderly paper, however, and it is always worth checking on the Diptera Nomenclator that the names Kröber uses are still appropriate to species in south Africa (e.g. Conops erythrocephala Fabricius, 1794 in Kröber's work almost certainly refers to Archiconops pseudoerythrocephalus Stuke, 2004)

*Incidentally, and as I was completely mis-explaining to a much-more-knowledgeable entomologist the other day (As a general rule, if I'm trying to explain something genuinely interesting to someone cleverer than me who doesn't know about it, I will forget everything that is inside my head and be embarassingly wrong about everything), Linnaeus Conops - and all his other invertebrate genera - lag behind several European spiders. Although no longer in its original genus, Enoplognatha ovata (Clerck, 1757) - the very first post on this blog - is one of those species which is still listed as being described one year before Linnaeus' Systema naturae, which is officially considered the starting-gun for the binomial naming system in invertebrates - to avoid taxonomists having to trawl through Pliny and older works to see who deserves the truly initial credit, so the whole thing is a bit of a scandal. 

Tuesday, 29 November 2016

Silky Lacewings (Psychopsidae)

I spend a lot of time trying to explain to people just how mind-numbingly diverse invertebrates can be.

And they are; take the lacewings - quite small, as insect orders* go, but still have over 600 species recorded from Zambia or a neighbouring country (based on information from the Lacewing Digital Library, an excellent resource that I probably rely on far too heavily).

So it's always pleasing to realise that I have encountered every member of a specific clade that enters the country, whether it's all the subspecies of a species, all the species of a genus or - in this case - all the members of the family.

Even if that family is the Psychopsidae, one of the least represented Neuropteran families in the continent with only eight species entering Africa, and only two likely to occur in Zambia (i.e. recorded in Zambia, or in multiple disjunct, bordering countries, in areas of comparable climate.

Before I bore you too much with endless text, here's one of them:

Silveira marshalli (McLachlan, 1902); came to lights on an unnamed tributary of the Luangwa. 

These eight species in three genera are actually a rather hefty share of the global diversity; both Australia and Asia have only a single genus each (although Australia's Psychopsis contains half of the global species).

They are extremely distinctive lacewings, at least within the region, instantly separated from all other lacewings by their broad, hairy wings; while some 'green' lacewings (Chrysopidae) and the Osmylids (no common name) are rather broad shouldered, none are quite so dramatic as these; they also tend to have rather longer antennae, and their bodies extend more noticeably in front of the wings.

Most are associated with woodland, where they have been suspected to pre-powder their eggs with vegetable matter, and fire them into leaf-litter while in flight (for more on that - and a general overview of the family - see Oswald, 1993); these presumably hatch into the usual, hyper-predatory little monsters that lacewing larvae usually are.

Formally, only one species is recorded from Zambia; but given that Zambia's predominant natural habitat is Miombo woodland (accounts vary as to whether this is a fire-dominated moist savannah, or is a type of subtropical deciduous forest currently massively degraded by man-made fires), it wasn't a stretch to assume that Silveira marshalli (McLachlan, 1902) - recorded from Botswana, Zimbabwe, South Africa and Zaire - would be present; it to lights in numbers in forested parts of Eastern province.

As for the other, Zygophlebius leoninas, Navás, 1910 - easily the most widespread African species, probably the most widespread species in the entire family (although as you can read in Oswald, 1994, there is a bit of a mess where it comes to records of this and the genitally-distinguished Z. zebra (Brauer, 1899) - I'd really like to be able to credit its appearance at a kitchen window in the increasingly developed Chongwe district to my ongoing tree-planting (and native-tree-encouraging) efforts, rather than the more likely conclusion that it's just another species that is slowly disappearing as every acre of ground is agriculturally exhausted and covered in concrete.

On that somewhat bleak note, here it is:

Zygophlebius leoninus Navás, 1910 in Chongwe District, Lusaka, Zambia. 

*Main taxonomic rankings, in order from largest to smallest: Domain (e.g. Eukaryota); Kingdom (e.g. Animalia); Phylum, (e.g. Arthropoda); Class (e.g. Insecta); Order (e.g. Neuroptera - lacewings); Family (e.g. Psychopsidae - Silky Lacewings); Genus (e.g. Silveira or Zygophlebius) and Species (e.g. Silveira marshalli)

**Yes, I pluralise words that end in 'x' with 'ces'. Sue me. 

Wednesday, 23 November 2016

The Stilt-Legged Flies - Micropezidae


True flies, to be specific; the two-winged members of the order Diptera  - I feel like we've neglected them a little*. They are, after all, the second largest order of insects in terms of described species, and - as I'm currently trying to come up with a rough key to the families of flies in Zambia, I'm currently painfully aware of just how diverse they are.

Based on recorded distributions of the 159 or so fly families globally (some are sometimes subsumed, there should be some 100 - not roughly, that is actually the number - families of flies present in Zambia.

Note that that isn't 100 'types' of flies, or 100 'species' of flies, but 100 families of true flies; some of which contain hundreds of known species in the region, some of which are only separable by dissection of the genitalia (ow) - and this may only represent a fraction of the actual diversity of this (understudied) country.

As you might imagine, these can be a nightmare to identify - even in groups where species are physically very different, because many taxonomists of history were so concerned with minute differences of genitalia that they neglected to mention the massive external differences between related genera and species (this is essentially why we have voucher specimens and museums: so that authors who think one feature is the most important don't end up making a taxonomic group completely unworkable. It doesn't always work).

Many of these 100 families, however, have only a few species in the region: while there are several dozen species further North in the continent, Southern Africa hosts only six species of the family Micropezidae, and records indicate that Zambia hosts even fewer.

To interrupt this long block of text, here's one of them: 

Mimegralla, probably Mimegralla fuelleborni (Enderlein, 1922, photographed on a farm outside of Mazabuka. 

You'd think with so few species, we'd know just what they do with their daily lives.

We do know a little, but the trouble with these flies is that they are fairly small and inconspicuous, and rarely - if ever - common, so that even with only six (known) species in the entirely of Africa below the Zambezi, the most insightful observation that the-usually-helpful Barraclough** made into their life histories was that their curious white fore-limbs could to be some sort of imitation of ichneumon wasps. Quite how it would benefit the fly to imitate a wasp which cannot sting remains unclear.

As to the rest? Well, one Indian species (Mimegralla coerulifrons (Macquart, 1843)) is a pest in commercial ginger and turmeric farming, and as a result has been quite well studied, and adults have been variously stated to be predatory (which, although this particular species location and behaviour suggested that it was there for the aphids, is doubtful applied across the entire family), and the suggestion that larvae are saprophagous (same link as the last, even though I should chase it the source, I know).

And if we throw in anecdotal claims, it gets even more confusing.

So let's not. Let's just enjoy them.

Here's another, this time Erythromyiella rufa (Hennig, 1935) from Lusaka South:

And, well, at some point I must learn how to write some sort of conclusion to these things instead of just trailing off..

*Not entirely - we have covered a few before - a long, long, long time ago: a rather unusual 'flesh fly' -  Dolichotachina caudata - which probably, like its closest well-studied relatives, acts as a cuckoo to burrow-nesting wasps; the extraorinary long-horned cranefly 
Megistocera filipes, never previously recorded in Zambia; the bizarre Stalk-eyed Diasemopsis meigenii, four hoverflies all trying - with varying success, to convince us that they are wasps or bees (Senaspis haemorrhoaHelophilus pendulusEpisyrphus balteatus and Metadon inermis), and the inexplicably named 'centurion' Chloromyia formosa

**If you are interested in Micropezidae south of the Zambezi and Kunene rivers (i.e. Zimbabwe, Botswana, South Africa, Southern Mozambique and probably-not-Namibia-because-they-are-mostly-forest-associated, do download the Barraclough (1996) paper, as it contains descriptions of all 6 regional species, and a decent key. I suspect that in the Northern parts of Zambia, Mozambique and Malawi, we get a few more recently-described (or undescribed) species - Tanzania certainly does - but for Southern Africa, this seems to be your lot. 

Monday, 14 November 2016

The Net Casting Spiders (Deinopidae)

Meet Deinopis Macleay, 1839. 

Male. Photographed in Chongwe District, Lusaka Prov., Zambia, November 2016, using Olympus E-420 and 3 KOOD lenses. 

Deinopis is the more iconic of the two genera of Net-Casting Spiders, distributed throughout the warmer regions of the world; it lends its name to their family (Deinopidae), and is the source of another common name for the family - Ogre-faced Spiders - and, locally at least, species of this genus are physically much larger, and difficult to overlook. This impressive male, found wandering on a driveway on a hot, humid night, had legs that spanned over 5cm.

To put this in context, his legs are very long; unusually long, you might think (if you are used to thinking about these things) for a spider that neither lives in caves (where anything and everything has a license to have very long legs) or live in a web

But this little Kangaude (Chewa - spider) does build a web. To those who know a little about spiders, this doesn't really resolve much: while his legs make slightly more sense, now, his eyes become something of a puzzle: of the other spiders blessed with such large and conspicuous peepers, most belong to either the Jumping Spiders (family Salticidae) or the Wolf Spiders (family Lycosidae); the vast majority of which are active, free-living predators, which use their eyes to see, hunt and capture prey - or, in the case of most jumping spiders - to communicate via semaphore.

To explain all of this, we have to turn to Deinopis' smaller and more abundant relative - and the only other genus in the family - Menneus Simon, 1876 - for a practical demonstration: 

Photographed in Chongwe, Lusaka, Zambia in April 2015. 

As already mentioned, one of the common names for this family of spider is Net-Casting Spider (and I will eventually find the direct Chewa translation for that, in theory); and they do precisely that; they wander around in search of a crossing point of nocturnal insects to wander through, and then, suspended above it by a simple thread, they spin an entire web between their (very long) front legs, and they wait.

And they wait.

Eventually something wanders past, and, seeing the movement, they whip down the net and voila, pre-wrapped meal - and a unique method of hunting that needs both a web and excellent vision.
Menneus - note the smaller eyes and the abdominal 'hump'. 

It is worth noting that Menneus' vision isn't quite like Deinopis'; they are probably most easily identified, in fact, by lacking the massive enlargement of the posterior median eyes seen in Deinopis; their eyes are still larger, on the whole, than those of most web-spinning spiders, but if it wasn't for their extraordinary webs, and the curious protuberances from their abdomen (earning them the alternative names of Camel-backed Spiders and Hump-Backed Spiders), they might be mistaken for free-living nursery-web spiders (family Pisauridae). 

Although identification to genus for this family is extremely easy - especially now that Avella and Avellopsis have been shoehorned into Menneus - you'll notice that I haven't listed a species name for either of our two guest-stars; although none appear to be recorded specifically from Zambia, a number of species are recorded from neighbouring countries and the wider region (see the World Spider Catalog page on the family); and - as the spiders are inconspicuous, nocturnal and easily overlooked - there is every chance that these do not belong to described species at all.

So I'll get back to you on that. 

Thursday, 20 October 2016

The Return of the Giant Earwig (No, not that extinct one).


They are probably the largest order of insects that I am inclined to forget exists; a quick google search puts the number of described species close to 2,000; with their generally inconspicuous lifestyles, it's easy to imagine that twice that many species actually exist.

An easier number to reach are how many are recorded from Zambia; a rather unimpressive 17 (given that our 8 neighbours average 45 species each; and excluding the two arid/desert nations brings that up to 59) are listed by Fabian Haas on his excellent map which you should definitely look at. Even this isn't concrete - as with everything else, the community at large seems to forget that Zambia used to be called Northern Rhodesia, and any pre-1965 records from 'Rhodesia - North' are generally attributed to the tropical quarters of Zimbabwe (even when they mention specifically Zambian sites, such as the Broken Hill mine; now Kabwe).

So far as I know, this is one of those 17:

Dacnodes cf. acutangula; photographed in Chongwe Distr., Lusaka Prov., Zambia in February 2016, using Olympus E420 with 40-150mm lens and 2 58mm KOOD magnifiers). 
This particular earwig is a member of the tropical genus Dacnodes, which I believe is largely Afrotropical, but with Dr. Haas' website playing up, I can't actually check up on). It is most probably Dacnodes acutangula Hincks, 1955, which is recorded from Zambia, but I'm not convinced of the distinction between D. acutangula and the more widespread Dacnodes caffra (Dohrn, 1867), which occurs in the wider region but doesn't appear to be recorded from Zambia.

And why should I care?

Well, because they're interesting. Partially phylogenetically - the position of Earwigs within the insects has changed quite a bit over the years; they spent a good while being squashed in next to beetles before they settled into their current - more comfortable - space next to the grasshoppers and stick-insects.

This one's most striking feature is its size; it is - 
at least for an earwig, massive. 
For a sense of scale, here it is sitting on a 58mm (diameter) magnifier lens: 

But aside from being big and difficult to classify, they have suffered the long indignity of superstition; the very name 'Earwig' is a contraction of their Old-English name Ear-Wigca (ear-crawler), a nod to the still-prevalent belief that they are inclined to crawl into people's ears - a lot of insects do this accidentally, but none - and certainly not earwigs - do it as a regular habit.

Instead, most earwigs are either innocuous decomposers, predators of small insects (which some species, possibly including Dacnodes, rather impressively grab in their forceps) or nibblers of pollen and flowers; most go for a combination of all three. They often get into trouble because of the last habit, but one of the most widely-maligned flower-nibblers (a much smaller earwig in the genus Forficula) recently received something of a reprieve when it was found that, on wind-pollinated crops, the effect of occasional pollen-nibbling is hugely offset by its tendency to eat something else, far more destructive: pollen mites. Despite conspicuous damage to flowers, earwigs can actually improve their effectiveness by eating away smaller, often overlooked pests which do much more damage.

A bit of a ramble, but the upshot is: most earwigs are really quite unfussy about what they eat. This is not unheard of for insects - most true crickets are similarly catholic in their tastes - but it is unusual. And it does mean that - despite that (fairly) high-profile extinction of the (really) Giant St. Helena Earwig, which is double the length and much, much chubbier than this one.

But to be perfectly honest, my favourite thing about this Earwig has very little to do with the Earwig itself: Some [insert long, long list of expletives here] stole my Laptop in January this year, and with it, my pictures of a lot (a very lot) of invertebrates that I hadn't yet backed up.

Three days later, this was the first species that I had lost the pictures of to return to my computer - and - half-drowned in a swimming pool - it was very tolerant of a few dozen camera-flashes.

But, moving on swiftly and without delay, to see how it (currently) fits into our slow-growing tree-of-life:

Also includes web-spinners and stoneflies. 
Also includes the Dictyoptera, such as Idolomantis dentifrons and Sibylla pretiosa 
- Neoptera                                   
As well as the Polyneopterans, includes most major insect orders such as Dichtha inflataOedemera nobilisOtiorhynchus atroapterus,Malachius bipustulatus , Phyllobius pomaceusCheilomenes lunataMelolontha melolonthaNeojulodis vittipennisDemetrias atricapillusAnthia fornasiniiLophyra cf. differensSynagris proserpinaVespula germanicaAstata tropicalisAnthophora furcataAndrena nigroaeneaEnicospilus, Zebronia pheniceCrambus pascuellaNemophora degeerellaSphinx ligustriLaelia robustaAcada biseriataMetisella willemiAnthocharis cardaminesCatopsilia florellaPapilio demodocusPanorpa germanicaChloromyia formosaSenaspis haemorrhoaHelophilus pendulusEpisyrphus balteatusMetadon inermisDiasemopsis meigeniiDolichotachina caudataMegistocera filipesPephricusGrypocoris stysiRanatra and Anoplocnemis curvipes.
- Metapterygota                             
As well as the Neoptera, includes dragon and damselflies such as Pseudagrion hageniLestinogomphus angustusRhyothemis semihyalinaOrthetrum brachiale and  Enallagma cyathigerum.
- Pterygota                                         
In addition to the Metapterygota, includes the primitive Mayflies. 
- Dicondylia                                        
In addition to the familiar winged insects, includes several primitive, wingless orders such as the silverfish.  
- Insecta                                                
- Hexapoda                                              
- Arthropoda                                             
- Ecdysozoa                                                   
Other than the Arthropoda, includes mostly small, worm-like animals. 
- Protostomia                                                   
As well as the Ecdysozoa, includes the Lophotrochozoa; such as Burtoa nilotica.
- Nephrozoa                                                         
 - Bilateralia                                                                 
- Eumetazoa                                                                  
- Animalia                                                                        
- Eukaryota                                                                        

Sunday, 26 October 2014

Hemiblossia bouvieri, Kraepelin, 1899 - OR - a small Arachnid and a mid-length essay on my motivations.

At this point, I'm almost certain.


Male. Photographed in September, 2011, in Chongwe District, Lusaka, Zambia, using Olympus E-420 DSLR, Zuiko 40-150mm lens and 3 KOOD magnifiers.
To do away with any suspense (is there any?) this tiny little fellow is a Solifuge, specifically (with probably around 97 percent certainty)

Hemiblossia bouvieri
Kraepelin, 1899

 These more-or-less friendly little beasties have a number of names, and probably just as many myths surrounding them - in Afrikaans, they are Haarskeerder or Baardskeerder, reflecting the (likely incorrect) belief that they cut off the hair and beards of unsuspecting people, and use the hair to line their nests; the names Rooiroman is simply a translation of the english 'Red-Romans', which, along with the rather charming Jerrymunglum, is of unknown origin to me.

The Afrikaans tradition is actually quite a sweet belief in comparison to some: in North Africa and the Middle East, Solifuges have picked up the Anglophone name of 'Camel Spider', with which comes a host of beliefs; that they can outrun camels, that they develop parasitically within camels and chew their way out, or that they simply chew their way in for no apparent reason; that they inject sleeping soldiers with anaesthetics and then strip away the flesh - to the bone - while they sleep... in parts of Masa(a)i East Africa, they are held to be venomous, and the conventional wisdom is that goats' blood should be applied to the wound in treatment of this venom.

In Chewa, I cannot find a name for them; we're settling, then, for another direct translation - the 'Sun spider' becomes 'Dzuwa Kanguade' .

This name comes with its own associations and stories - the name for the order, 'Solifugae' literally means 'those that flee from the sun', which isn't - unusually - entirely inaccurate, but more on that later.

You see, the Solifuges are plagued by dichotomies. They have, for an arthropod, a most extraordinarily advanced eye - as if it wasn't unusual enough to have only the two, theirs represents, in evolutionary terms, the last step in the chain between the ever-popular compound eye and the visually rewarding 'simple' eye that we vertebrates are so lucky to possess; although the Solifuge eye is small, it is - at least in theory - capable of passing on a really quite accurate image of the world around them to their brain.

A good many species, though, hunt only at night and furthermore, almost entirely by touch.

The order is split between nocturnal and diurnal species, but - unlike, for example, the birds, where the nocturnal species are almost all found in just two evolutionary lines (Caprimulgiformes and Strigiformes), nocturnal species make up a significant chunk of a great many of the larger genera, and most - if not all - of the families show representatives of both groups.

Of the day active species, many are at their most active in the hottest part of the day; which - in the tropics - is a rather questionable life choice for a small, relatively soft-bodied invertebrate; presumably to offset this, these thermally naive species are often noted for their tendency to chase shadows - which, although it presumably limits their chances of being boiled alive at an essentially predator-free time of day, does mean that they are frequently perceived as aggressors by the already quite invertebrate-unfriendly human race, and met with a boot or a faceful of insecticide.

Before we get onto talking about me, there is one more dichotomy to mention: these are small, relatively slow moving (very fast within their size-group, but not compared to, say, us) invertebrates, whose inability to cross geographic barriers is made apparent by the restriction of entire families to Southern Africa, and yet - along with hundreds of species recorded only from single sites - there are a handful of species that are - apparently validly - recorded from the entirety of Sub-Saharan Africa.

And now onto the other part. 

Several months ago, I posted this picture on the - wonderful - Spider Club of Southern Africa face-book page, hoping that someone could help me get started on its identification: my experience with this group was not remotely taxonomic - it consisted largely of panicking when one fell off the ceiling into my food.

Very quickly, someone told me that it looked like a member of a particular family (Daesiidae), but they couldn't be sure.

Shortly thereafter, an authority whose opinion I held, and continue to hold, in great esteem, posted their 2 cents.

They stated that these could not be identified - even to family - from a photograph, and that a captive male was required for any form of I.D.

This might very well have been the end of it, except that, off the back of the first post, I had already been digging up what I could (on the gobsmackingly fantastic and completely FREE biodiversity heritage library) on the Daesiidae within southern Africa.

I'd dug up quite a lot.

I'd identified that mine was male, and I'd identified that its peculiar, membranous flagellum was clearly unlike the vast majority of illustrations I could find of genera known to occur in southern africa. Several families could be quite easily ruled out and, within the only family that couldn't, most genera were similarly quite clearly inappropriate for my little (tiny) find.

So I said as much on the post, and asked whether, given that I understood that a great many Solifugae were impossible to identify from photographs, I was correct in all my readings of the word 'Distinctive', 'Unique' and 'Diagnostic' in the original literature.

The response wasn't snarky. It wasn't even unkind. But it was dismissive.

In that response, it was abundantly clear that this acknowledged expert - whom only hours previously I have been ecstatic to have received any contact from at all - had not even read what I had written. This should not have been a problem - if there are two things that I am exceptionally good at, it's being told that I'm wrong, and falling off things. The skin of my forearms and knees is really quite thick, and more importantly, my brain is by now quite happy to let go of something it formerly held to be true.

So all should, you would think, be as it was. I should have moved on and left the Solifuges alone, safe in the knowledge that in a few years time, they would be genetically barcoded, and we could identify them by snipping bits off living, breathing organisms and sending it to some cold, mechanical lab in Boston. Or something.

But my dismisser also repeated something he had said in his first statement. Something which I now had empirical proof was abundantly not true: that a male was required for any concrete identification.

This is not an unusual view - males of many animals are not usually more abundant, but they are usually more conspicuous and, often, more unusual in their form, and this is reflected in descriptions of the types.

However, this species, and the genus that Kraepelin created for it, were originally described from females.

If a species and a genus that are still held to be valid over a century later, even when a dozen or so species variously described from males and females have be added to the genus since, based on a sample composed entirely of females, it's safe to say that some identification can be made within this group based on the females.

My dismisser, in my admittedly rather warped mind, had used his position as a pre-eminent arachnologist to fuel a lie. I was, in a word, enraged.

Which is why now, one hundred species and a third of the way through transcribing the entirety of the type descriptions of known Southern African Solifuges, I can tell you that the person most responsible for this somewhat misogynistic view of arachnid identification was a gentleman by the name of R. F. Lawrence, who had the common indecency to die, and leave southern Africa without its most prolific author on these wonderful little monsters. The forty years that have passed since that saw increasingly few publications, and without publications and citations, much of the original literature more-or-less disappeared, making it essentially impossible to identify species. The fact that Roewer had, in 1933, written a lengthy treatise on Solifugae from all over the world was somewhat irrelevant if nobody knew it existed. South Africa's first noteworthy Boer (actually half-Boer) scientist, William Purcell, might as well have never been born, for all the inattention to almost everything he had ever written .

This is a travesty, not only because I have an automatic soft-spot for people who share my genetic mix-ups, but also because knowledge was degrading. If it got much further, the original descriptions would be better off scrapped, and, at least for my favourite subcontinent, the entire order would have be redescribed as though it was new; considering how limited many Solifuges are in their distribution, quite a few of them could very well have gone extinct in the last century, and if their original descriptions disappeared - what then? Would we not count that as a loss because, for taxonomic purposes, they never existed?

I told you that this was going to be a mid-length essay; I lied. I know it's a long one. I know it borders on the fantastical, but these concerns aren't entirely unreal. This order has an extraordinary level of endemism; endemic species are the first to be pushed over the edge and into oblivion, and if no-one even knows that they exist, how would we know if they had ceased to?

Well, now that doesn't have to happen. The Biodiversity Heritage Library is a fantastic project to put all of this information online, and - even if I give up and fail halfway through my personal attack on these type descriptions - information is being clawed back from the edge of nothing.

The internet, in its own special way, is saving the world.

No, I'm not certifiable. Daylight saving has ended, which is always unsettling. 

If anyone is interested in this group more generally, I really recommend The Solpugid Website, which, although it lacks much in the way of information on African species, does, crucially, have a lengthy list of all known citations for this order, which is even more valuable when you realise that many of these come with downloadable PDFs of the same citations.

For those that don't? BHL. 

Thursday, 16 October 2014

Potentially Tomopterna cryptotis (Boulenger, 1907)

This little chule troubles me.

Photographed 04/01/2014 using Olympus E-420 DSLR with 40-150mm Zuiko lens and 1 KOOD magnifier. Chongwe, Lusaka, Zambia.

I had originally filed it as Leptopelis bocagii; a mistake made much easier by the here almost perfectly round pupil; unlike Leptopelis, however, I'm fairly sure that in daylight, this little frog has a horizontal pupil.

It does, at a glance, resemble Leptopelis as found on the farm - it is a chubby, pale frog, active at night and not overly active, with a faint, symmetrical dorsal pattern. It is blunt-faced, rough-skinned, and - unlike our other locally common chubby, burrowing frog, Breviceps powerii - it can, at least in theory, jump.

But then there came doubt. Leptopelis bocagii, and our other Arthroleptid (Arthroleptis stenodactylus) both show rough skin on their bellies; this one, although it's not at its most visible here, has a clean, bright white belly all the way back.

Unlike L. bocagii , it also has a little, almost glandular ridge running around the corner of its mouth, giving it a decidedly disapproving expression that seems to be most commonly associated with Ranidae, and certainly seems to be absent from the Arthroleptidae. In fact, ignoring the colouring - which is in the first place very variable, and in the second place is often paler at night, especially when a frog's been taking a swim in a chlorinated pool - and noting that the pupil is, in this instance, uninformative, it's actually got very little to relate him to Leptopelis; the snout is too bulbous, the legs are too short, and the tympanum (ear) is very nearly invisible.

And finally, there was a little white protuberance on the heel of the back foot:

 Which all seems to point, at least in theory, to the sand frogs (Tomopterna). The nearly invisible Tympanum - which is somewhat more visible in the first picture, where the animal's overall colour is paler - would suggest Tomopterna cryptotis, but at least two other species - T. krugerensis and T. tandyi; if this is, actually, Tomopterna at all, the call is listed as the only reliable way to separate these three; T. cryptotis is our tentative identification only because the other two have not, to my knowledge, been recorded from Zambia.

It's worth noting that they are not usually found in swimming pools; they are typically associated with rivers and temporary pools, where they bury themselves in the sand when the water retreats - the little flange on the foot is an aid to rapid burrowing. There are, however, several small streams and rivers in the wider area, some of them barely an hours walk away, which quite likely went from dry to flooded in the weeks before this little one was found.

As far as frogs are concerned, I have bypassed my commitment to freely available literature, and instead use Alan Channing's Amphibians of Central and Southern Africa; it's awesome and I really feel that more people should own it.

Friday, 25 July 2014

Trigonidium cicindeloides (possibly), Rambur 1838


It's summer. It's very hot. There are lots of insects around and about in the UK right now, and I've been tormenting them with the camera while completely failing to maintain this blog.

This is not one of them:

Male? Chongwe, Lusaka, Zambia, March 2013. Olympus E-420 DSLR with Zuiko 40-150mm lens and 3 KOOD magnifiers.

This little chukululu is, as you may guess from the Chewa introduction, a Zambian. In other languages, this widespread subfamily of crickets are known as Sword-tail crickets  in English, and Käfergrille (~black cricket) in German. To, as we've been attempting without much success, give it a more specific label in Chewa, we could translate the English directly to Lupanga-Khombo Chukululu, or perhaps, with an attempt at grammatical correctness, Chukululu ndi Khombo yonga Lupanga.

A more specific identity is a little iffy; it does belong to the genus Trigonidium, and bears a very strong resemblance to members of its putative species,

Trigonidium (Trigonidium) cicindeloides
Rambur, 1838.

There are, however, a fair number of Trigonidium species native to sub-Saharan Africa. None of them, interestingly, are noted by the - brilliant -  Orthoptera Species File as recorded from Zambia, but at least two very distinct forms are present in Chongwe district, which correspond in form closely to two widely distributed species recorded from neighbouring countries or - in the case of T. cicindeloides - recorded from an interrupted range of countries that suggest its presence in Zambia. While there are other species described from neighbouring countries, these are of such limited known range and recent distribution that it would be incautious to predict their presence in Zambia.

The location itself is further suggestive of the species the two so closely resemble - both were in an agricultural, regularly disturbed area not far from Lusaka city; notably widespread species, recorded - as both this and the (unshown) T. erythrocephala are - primarily from the most developed corners of the continent - are more likely to have the adaptability to survive, and even thrive, in such a human-dominated environment.

So, waffle over, and another angle of our little lupanga-khombo chukululu

Eukaryota; Animalia; Eumetazoa; Bilateralia; Nephrozoa; Protostomia; Ecdysozoa; Arthropoda; Hexapoda; Insecta; Dicondylia; Pterygota; Metapterygota; Neoptera; Polyneoptera; Anartioptera; Polyorthoptera; Orthopterida; Panorthoptera; Orthoptera; Ensifera; Grylloidea; Gryllidae; Trigonidiinae; Trigonidiini.