A wide range of modern Insects survive as ectoparasites of
vertebrates, either by living permanently on their hosts, as with Fleas or by
visiting animals to feed, as with Mosquitoes. However identifying such
behaviour in the fossil record is difficult, and while a variety of parasitic
insects are known from Cainozoic deposits, only Fleas are known from the
Mesozoic, when most modern Insect groups are thought to have originated.
In a paper published in the journal eLIFE on 24 June 2014, a team of
scientists led by Jun Chen of the Institute of Geology and Paleontology at LinyiUniversity describe a remarkable Fly larvae (maggot) from the Middle Jurasic Daohugou
beds of Ningcheng County in Inner Mongolia.
The larvaeare formally named as Qiyia jurassica,
where ‘Qiyia’ means ‘bizarre’ in
Chinese and ‘jurassica’ refers to the
age of the specimens. The species is described from five specimens preserved as
surface impressions on grey siltstone. Two of these specimens have been
compressed laterally and three dorsally, enabling the species to be examined
from both angles.
Qiyia jurassica from the Middle Jurassic epoch of Daohugou, China. (A) Specimen
preserved in lateral view. (B) Specimen preserved in lateral view under alcohol
(horizontal mirror image). (C) Head capsule of specimen preserved in lateral
view. (D) Head and thorax of specimen preserved in lateral view. (E) Enlargement
and reconstruction of the mandible of specimen preserved in lateral view;note
the longitudinal groove. (F) Fifth proleg of specimen preserved in lateral view;
note stiff, upward directed bristles which are distinctly longer than setae on
body. (G) Last abdominal segment of specimen preserved in lateral view. Abbreviations:
ap, anal papilla; p, proleg; pr, process of ridge; tp, terminal process. (Scale
bars: 5 mm in A, B, 1 mm in D, F, G, and 0.5 mm in C, E). Chen et al. (2014).
The specimens range from 18.1 mm to 23.8 mm in length. It has
elongate, sickle-shaped mandibles, which are interpreted as an adaption to
blood-sucking, and what appears to be a round sucker on the dorsal surface of
its thorax, presumably with which to adhere itself to its prey.
Qiyia jurassica from the Middle Jurassic epoch of Daohugou, China. (A) Specimen
preserved in dorsal view under alcohol. (B) Head and thorax of specimen preserved in
dorsal view; note the underlying thoracic sucker. (C) Terminal processesof specimen
preserved in dorsal view. (D) Reconstruction of sucker. The sucker consists of
a circular suction disc with centralopening and thin peripheral area. Six
robust, radially arranged ridges are covered by soft skin with small spines. (E)
Head and thorax of specimen preserved in dorsal view; note the deformed
mandible. ap, anal papilla; p, proleg; pr, processof ridge; tp, terminal
process; tr, tentorialrod. (Scale bars: 5 mm in A, 1 mm in B, C, E). Chen et al. (2014).
The larvae are interpreted as having belonged to a Water Snipe Fly (Athericidae).
Modern Water Snipe Flies are blood parasites of vertebrates as adults, with
larvae that are aquatic predators, living in fast flowing water and targeting
smaller invertebrates. The Water Snipe Flies are considered to be the sister
group to the Horse Flies (Tabanidae), making it likely that the common ancestor
of the two groups was also a blood sucker, although neither group produces
blood drinking larvae today, so it is unclear whether the adaptation seen in Qiyiajurassica is a separate innovation
(the larvae of all True Flies metamorphose on maturity, and seldom have a
larval lifestyle that even remotely resembles that of adults), or whether
parasitism was the ancestral state in both larval and adult members of these
groups. Fossils of adult Horse and Water Snipe Flies are known from the Early
Cretaceous of southern England, with molecular studies suggesting the groups
diverged in the Early-to-Middle Jurassic, but this is the first fossil evidence
of either group prior to the Cretaceous.
Reconstruction of Qiyia jurassica
in lateral view. Chen et al. (2014).
The Daohugou beds are interpreted as a lake environment, with
largely still waters. No fish have been recorded from these beds, but
Salamanders are extremely numerous here, and were presumably the host group for
Qiyia jurassica. Salamanders have thin
skin, making them vulnerable to blood-sucking parasites, and those from the Daohugou
beds are believed to have been aquatic throughout their entire lifecycle,
reaching maximum lengths of about 500 mm. This is about the right size for a
parasite the size of Qiyia jurassica,
and means that an attached larvae would have been unlikely to have been removed
from the water by its host.
See also…
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(slightly erroneous) reputation for being tolerant of cold conditions.
In fact a few species are capable of remaining active in winter, with
some even mating and laying eggs beneath snow cover, but other... 
A giant Spider from the Middle Jurassic Daohugou Biota. In 2011 Paul Seldon of the College of Life Sciences at Capital Normal University in Beijing, the Paleontological Institute and Department of Geology at the University of Kansas and the Natural History Museum in London, along with ChungKun Shih and Dong Ren, also of the College
of Life Sciences at Capital Normal University, described a large female
Spider...
A new species of Osmylid from the Middle Jurassic Daohugou Biota of Inner Mongolia Osmylids (Osmylidae) are a group of Neuropteran Insects with a fossil
record dating back to the Early Jurassic and are still in existence
today. They appear to have been at their most numerous and diverse in
the Middle-Late Jurassic, with a number of lineages apparently
disappearing at the Jurassic-Cretaceous...
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