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:
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| 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.
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:
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:
-Pygidicraninae
-Pygidicranidae
-Pygidicranoidea
-Protodermaptera
-Neodermaptera
-Dermaptera
-Dermapterida
-Polyorthoptera
Also includes the Orthoptera, such as Trigonidium cicindeloides, Tettigonia viridissima, Stictogryllacris punctata, Enyaliopsis, Zonocerus elegans, Humbe tenuicornis, Lobosceliana loboscelis, Cyathosternum prehensile, Heteropternis thoracica and Pseudothericles jallae.
-Anartioptera
Also includes web-spinners and stoneflies.
-Polyneoptera
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 inflata, Oedemera nobilis, Otiorhynchus atroapterus,Malachius bipustulatus , Phyllobius pomaceus, Cheilomenes lunata, Melolontha melolontha, Neojulodis vittipennis, Demetrias atricapillus, Anthia fornasinii, Lophyra cf. differens, Synagris proserpina, Vespula germanica, Astata tropicalis, Anthophora furcata, Andrena nigroaenea, Enicospilus, Zebronia phenice, Crambus pascuella, Nemophora degeerella, Sphinx ligustri, Laelia robusta, Acada biseriata, Metisella willemi, Anthocharis cardamines, Catopsilia florella, Papilio demodocus, Panorpa germanica, Chloromyia formosa, Senaspis haemorrhoa, Helophilus pendulus, Episyrphus balteatus, Metadon inermis, Diasemopsis meigenii, Dolichotachina caudata, Megistocera filipes, Pephricus, Grypocoris stysi, Ranatra and Anoplocnemis curvipes.
- Metapterygota
As well as the Neoptera, includes dragon and damselflies such as Pseudagrion hageni, Lestinogomphus angustus, Rhyothemis semihyalina, Orthetrum 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
Includes insects and their hard-bodied relatives, such as Nephila fenestrata, Enoplognatha ovata, Argiope bruennichi, Alopecosa barbipes, Phrynarachne rugosa, Hyllus argyrotoxus, Enoplognatha ovata, Argiope bruennichi, Pardosa amentata, Dysdera crocata, Dicranopalpus ramosus, Ligia oceanica and Hemiblossia bouvieri.
- 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
In addition to the Protostomes, includes Deuterostomes such as Synchiropus splendidus, Tomopterna cryptotis, Rana temporaria, Chiromantis xerampelina, Breviceps poweri, Kassina senegalensis, Agama armata, Chameleo dilepis, Psammophis mossambicus, Thelotornis capensis, Afroablepharus wahlbergii, Trachylepis varia, Trachylepis striata wahlbergi, Zootoca vivipara, Lygodactylus capensis, Podiceps cristatus, Caprimulgus pectoralis, Tockus alboterminatus, Larus argentatus, Sterna hirundo, Burhinus vermiculatus, Troglodytes troglodytes, Megaceryle maxima, Ardea goliath, Chalcophaps indica, Stigmatopelia senegalensis, Hipposideros vittatus and Syncerus caffer.
- Bilateralia
- Eumetazoa
- Animalia
- Eukaryota
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