Einfeldia australiensis (Freeman, 1961)

As Xenochironomus australiensis

According to Cranston (Cranston et al. 2016) the type series is mixed.  The Holotype is Einfeldia, but two of the paratypes are an undescribed species of Xenochironomus.


The adult male was redescribed by Cranston (Cranston et al. 2016), but the female is still unknown.

Wing length about 2.75-3.5 mm, VR 1.07; AR about 2.7; LR1 1.57-1.65; LR2 0.46-0.48; LR3 0.55-0.60.  Fore tarsal beard sparse, BR 5.0.
Colour greenish; thorax yellow-brown with vittae scarcely darker; legs green, forelegs with darker tibia and tarsomeres, mid and hind legs with dark tarsomeres; abdomen light green becoming darker posteriorly.  Freeman classed the thorax as green with yellowish-red thoracic vittae.
Frontal tubercles present (Freeman stated they were absent) globular, about 5-7 µm across.  Palpal proportions (segs. 2 - 5) 50-65 : 120-175 : 150-200 : 210-320.  15-18 clypeal setae.
Thorax with antepronotal lobes narrow dorsally and fused at shallow notch, slight indication of a scutal tubercle.  Setae - 19-21 acrostichals in irregular biserial row, 6-11 dorsocentrals, 5-6 prealars, about 16 scutellars in two rows.
Dorsomedial setae of TIX in pair of clusters, about 11-20 in each cluster.  Anal point thick and heavily downturned.  Gonostylus slightly widened in midsection, tapering slightly at tip.

Pupa: (described by Cranston): Length about 7 mm, medium brown, with weak abdominal apophyses.  Cephalic tubercle roughly conical, abt 70 µm long and with short (about 20 µm) pale seta.
Hook row on TII undivided, with 55-60 uniserial hooks, covering about 50% of segment width.  No setae in conjunctives.  Posterolateral spur of segment VIII with about 5-7 brownish, basally separated, tapering spines about 80-110 µm long.  Anal lobe with dense, uniserial fringe of 70-80 taeniae, with single dorsal seta inserted quite anterolaterally.  Pedes spurii A strongly developed on SIV, pedes spurii B well developed on II, absent on III.

Larva: Rather like a Kiefferulus larva in gross morphology.  Length about 7-12.5 mm, no lateral tubules, one pair of ventral tubules about 1.08-1.16 mm in length; anal tubules about 360 µm long and about twice as long as wide.
Head capsule generally pale, but posterior third of the gula may be darkened. Dorsal surface with fused frontoclypeus, with large ovoid to heart shaped fenestra between the S4 setae.
Mentum with 15 teeth, c1 tooth domed, c2 teeth variably visible depending on wear.  Laterals decrease evenly (i.e. type I).  Ventromental plates separated by about 13-15% of mentum width, with about 40-46 striae, which extend almost to margin, terminating in 1-2 spinules, VMR about 0.37-0.38.
Pecten epipharyngis usually with three scales (but see note under Molecular Data, below), each with about 4-8 variably shaped teeth.
Antenna with basal segment about 3.3 times longer than wide, RO in basal third.  Antennal proportions 88-93 : 25-28 : 12-15 : 12-15 : 7.  AR 1.4-1.6.
Premandible with two teeth of approximately equal length, inner tooth at least twice the width of the outer tooth.
Mandible with small accessory dorsal tooth outer tooth; no furrows near the base.

Cytology: 3 polytene chromosomes with little evidence of the Keyl arms.  However the arm corresponding to arm G is fused to one arm, possibly arm E, of a previously metacentric chromosome (confirmed by presence of 4 polytene chromosomes in other Einfeldia species).  The fused arm G has two BRs but no nucleolus.  The nucleolus is developed near the middle of an arm of another chromosome.  The two metacentric chromosomes have heterochromatic bands which probably represent the centromeres.
No polymorphism in the studied specimens.

Molecular Data:
mtCOI - Sequence now available suggests that there may be two forms (species?) included under this name.  The sequences are from larvae, with no associated adults.  The larval head capsules are very similar, but there are a couple of possible differences – notably that Cranston (in Cranston et al. 2016) illustrates the pecten ephipharyngis comprising three scales, whereas in some larvae there are two, or perhaps only one, scales.  Further data, particularly from adults, are needed to resolve the situation.

Australian Capital Territory - Lake McKenzie, Jervis Bay (35.06°S, 150.68°E).
New South Wales - Blue Lagoon dune lake;  Pond #3, Botany wetlands, Sydney (33.935°S, 151.208°E);  Oxford Falls (type locality -types in BNHM, London).
Queensland - Ocean Lake, Fraser Island (24.925°S, 153.273°E).
South Australia - Lake Edward, nr. Kalangadoo (37.63°S, 140.58°E); Valley Lake, Mt. Gambier (37.50°S, 140.75°E),
Victoria - Lake Little Beatle (37.79°S, 148.42°E); Swan Lake (38.20°S, 141.32°E)

[ Return to Index | Go to References ]

Created: 26 November 2017
Access: Unrestricted
Copyright © 2017, Jon Martin.