Armoured  Harvestmen  -  Suborder:  Laniatores
      The Armoured Harvestmen, or Laniatores, are the largest suborder of the Eupnoi with, as of January 2024,  4,254 *  species divided amongst 44 families in either 8 or 9 superfamilies.  ('iNaturalist' lists the Sandokanidae as a family within the Superfamily: Epedanoidea whereas the 'Catalogue of Life' lists it as a superfamily.)   It is worth noting that the 4,000+ species in the suborder are spread over 1,335 genera which means that there are only just over 3 species per genus and that, in itself, is an indication of how much split up the Order: Opilliones is. Obviously there is a lot of work yet to be done to work out the phylogenetic relationships in the Order.
      With the number of species running in the thousands, one would expect a fair degree of variation both in size and form and in that regard we have no cause for disappointment.  Whereas as many are somewhat monochrome in colour and simple in appearance, there are also, particularly in South America, numerous species that are exquisitely  beautiful.  And some that are outright monstrous.   Their 'armour' a hard chitinous plate covering the upper side of the body is often adorned, with spikes and knobs of various lentgths and can have patches of bright colouring.  Likewise legs and pedipalps may carry numerous spikes creating a rather fearsome image.
*    Interestingly, only 9 fossil occurrences are known to date confirming the earlier mentioned notion that Opilliones are indeed very much under represented in the fossil record.
      Laniatores generally prefer humid habitats and are commonly found sheltering under logs and stones or hiding in leaf litter.  There are also species that can be found in caves.  In size they are commonly between 4 and 14 millimeters long but their apparent size can be larger if they possess large, spiny pedipalps which are usually carried folded and forward facing.  Their legs are relatively short, usually no more than 10x the bodylength but for most species the ratio is smaller still.  The suborder itself is divided into two Infraorders.   The Grassatores, the larger of the two with 3,741 species, and the Insidiatores.    
      It was recently proven that the hairs on the pedipalps of many Opilliones, including Laniatores, are able to secrete a sticky fluid that assists the harvestmen greatly in capturing its prey.  Whereas the idea had been hypothesized quite some time ago it wasn't until video using a high-speed camera was produced that it became a proven fact.   (See: Wolff, J. et al, 2014.)  Not only is the substance sticky, it shows to have non-Newtonian properties that cause it to become even more sticky when the prey animal starts to struggle.  No doubt this will go a long way explaining why such a slightly built creature such as a harvestman is capable of subdueing and killing spiders and insects larger than itself.  
References  and  links:
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>      Pinto da Rocha, R., Machado, G. & Giribet, G., (2007).  Harvestmen: The Biology of Opiliones.  Harvard University Press, London.
>      Wolff, J.,  Schönhofer, A.,  Schaber, C.  and  Gorb, S.,  (2014).    'Gluing the 'unwettable': soil-dwelling harvestmen use viscoelastic fluids for capturing springtails.'   The Journal of Experimental Biology. 217. 3535-44.  DOI:10.1242/jeb.108852. 

      https://www.catalogueoflife.org/data/taxon/FXK
       https://en.wikipedia.org/wiki/Non-Newtonian_fluid​
​      https://en.wikipedia.org/wiki/Opiliones
      https://inaturalist.ala.org.au/taxa/535008-Sandokanidae
      https://www.mindat.org/taxon-P271418.html
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Header photo:
​Nick Lambert.
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