Australian Entomologist 47 (2): 53–72 (26 June 2020) 53
AUSTRALIAN SPECIES OF DICRANOMYIA (IDIOGLOCHINA)
(DIPTERA: TIPULOIDEA: LIMONIIDAE)
GUNTHER THEISCHINGER1, ZACARIAH D. BILLINGHAM2 and
ALBERT G. ORR3
1Australian Museum, Entomology, 6 College Street, Sydney, NSW, 2010
2GHD Pty Ltd, 180 Lonsdale St, Melbourne, Vic., 3000
3Grith School of the Environment, Grith University, Nathan, Qld, 4111
The species of Dicranomyia (Idioglochina) Alexander, 1921 known from Australia are reviewed
in detail and a new species, Dicranomyia (Idioglochina) caloundrae sp. n. is described. This new
species from the littoral zone of a marine rocky shore at Caloundra, Queensland, is illustrated and
compared with the two species previously known from Australia, and a key to the males of Australian
Dicranomyia (Idioglochina) is presented. Observations on the biology of the new species as made by
the collector (AGO) and life photographs are presented.
Key Words: marine insects, natural history, new species
The species of the Dicranomyia Stephens, 1829 subgenus Idioglochina
Alexander, 1921 may be restricted to at least some of the lands surrounded by
or bordering the Pacic and Indian oceans (known from Australia, New Guinea,
Indonesia, Taiwan, Japan, New Zealand, New Caledonia, Vanuatu, Tonga,
Samoa, Micronesia, Mauritius, Comoros, Seychelles, South Africa, Canada,
USA, Chile). From the known habits and general occurrence it appears that
all species are marine or coastal and require saltwater as a habitat for the early
stages (Alexander 1972). In the World Catalogue of Tipuloidea 28 species-group
taxa are listed, among them two species from tropical Australia (Oosterbroek
2019). The collection by the third author of a D. (Idioglochina) species from
subtropical Australia was therefore sucient reason to review the information
and material available on the described Australian species (Fig. 1). The state of
the type specimens created problems and made it necessary for us to repeat the
complete original descriptions of both species. The fresh material from Caloundra
is described as new below. Also described and illustrated are larva and pupal
exuviae. Biological observations, including a quantitative study of phenology,
Materials and Methods
Specimens of adults were collected by AGO either by hand or using an aerial
insect net and preserved dry or in 70% ethanol; immature stages were recovered
from scrapings of Corallina algae examined under a dissecting microscope;
pupal exuviae were removed from the algal substrate by hand when they could
be located by the presence of an emerging adult. Immature stages were preserved
in 70% ethanol. As a result of this preservation, the coloration of specimens
might have changed from the natural state. The illustrations of the male genitalia
Fig. 1. Distribution of the Australian species of Dicranomyia (Idioglochina), image
modied from SIO, NOAA, U.S. Navy, NGA, GEBCO map data, Google Earth.
54 Australian Entomologist
(hypopygium) are from specimens cleared in KOH and displayed in glycerol.
Type material of known species deposited in the Alexander Collection (AC) in the
Smithsonian Institution (SI) in Washington DC and in the Queensland Museum
(QM) was studied. Specimens of the newly described species have been lodged
in the Queensland Museum (QM) in Brisbane, the Australian Museum (AM) in
Sydney, in the AC (Alexander Collection, Smithsonian Institution, in Washington
D.C.) and in the Museum Victoria (NMV) in Melbourne. Specimens retained by
the second author are kept in a vouchered research collection at the GHD Water
Sciences Laboratory in Melbourne to aid in ongoing survey work and for use
in DNA barcoding studies. DNA sequencing eorts are ongoing; sequence and
specimen data are stored in the Barcode of Life Data Systems (BOLD) database
and, upon any future publication of genetic data, sequences will be published to
Descriptive terminology for the new species is in accord with McAlpine (1981).
In the descriptive texts taken from Alexander (1922, 1930) his original terms are
Casual observations of phenology were made by AGO during 2017 and 2018,
chiey at low spring tides in the afternoons from June to September. From 26
June to 6 August 2019 inclusive a quantitative estimate of relative abundance
was made each day at approximately low tide. A transect of 40 m was walked at
a steady pace with individuals 1 m either side counted. On these days a sample of
47 (2): 53–72 (2020) 55
10–20 specimens were collected and released to monitor the sex ratio, and various
behavioural observations were recorded.
Genus Dicranomyia Stephens
Dicranomyia Stephens, 1829: 32.
Type species: Limnobia modesta Meigen, 1818, by designation of Coquillett,
Subgenus Idioglochina Alexander
Dicranomyia (Idioglochina) Alexander, 1921: 207.
Limonia (Idioglochina) Alexander, 1928: 241.
Type species: Rhipidia tusilata Alexander, 1921, by original designation.
Diagnosis (from Theischinger 1996). Mouth-parts shorter than remainder of
head; antenna 14-segmented, agellomeres markedly extended to produce
serrate to almost pectinate appearance (particularly in male); eyes glabrous; wing
venation: Sc short, ending well proximal to origin of Rs; three branches of R
reaching margin; M with two branches; dm not hexagonal or proximally pointed;
r-m not in direct alignment with Rs; CuA2 not fused with A1; no supernumerary
Dicranomyia (Idioglochina) australiensis Alexander
Dicranomyia (Idioglochina) australiensis Alexander, 1922: 581.
Holotype ♂. North Australia, Moa Isl., 1921, G.F. Hill. Studied, photographs gs 2–6.
According to Alexander (1922) the holotype was preserved in the collection of the
writer. In 1989 GT did not nd it in AC (SI). In 2019, however it was found in QM,
having been sent in 1983 on loan to E.N. Marks (1918–2002) (J. Gelhaus pers.
comm.). Marks, who had an interest in marine y fauna, retired in 1983 following
10 years working at the Queensland Institute of Medical Research (QIMR),
Brisbane. Her collection, mainly of mosquitoes, was transferred from QIMR to
the University of Queensland shortly after. The University of Queensland Insect
Collection was donated to the Queensland Museum in 2011 (G. Daniels & C.
Lambkin (QM) pers. comm.)
Description (from Alexander 1922).
General colouration brown, the pleura pruinose; wings grey; cell 1st M2 about as
long as vein Cu1 beyond it.
♂. Length, 4.5 mm; wing, 4.8 mm. ♀. Length, 4.5 mm; wing, 5 mm.
Rostrum and the very short palpi brown. Antennae light yellowish-brown, the
scape a little more yellowish. Head brown, the orbits somewhat paler.
Mesonotum greyish brown, the dorsum clearer brown, the humeral region
Figs 2–4. Dicranomyia (Idioglochina) australiensis Alexander, holotype ♂: (2)
slide with antenna, wing and label; (3) wing; (4) part of specimen.
56 Australian Entomologist
slightly paler; scutellum obscure yellow. In the female, the mesonotum is more
rufous brown. Pleura grey, the lateral sclerites of the postnotum more whitish.
Halteres yellow, the knobs brown. Legs with the coxae brown, dusted with grey;
trochanters yellowish-brown; remainder of the legs pale brown. Wings grey;
veins brown. Venation: As in D. (I.) debeauforti (de Meijere) but Rs more gently
arcuated, so cell 1st R1 is elongate-oval in outline; cell 1st M2 about as long as
vein Cu1 beyond it. In the female, Rs is straighter.
Abdomen brown, the hypopygium obscure yellow. Ovipositor with the valves
long and straight.
Distribution. Known from the type locality only.
Figs 5, 6. Dicranomyia (Idioglochina) australiensis Alexander, holotype ♂: (5) part
of specimen with detail of antenna; (6) abdomen, ventral.
47 (2): 53–72 (2020) 57
Dicranomyia (Idioglochina) perkinsiana (Alexander)
(Figs 1, 7–10)
Limonia (Idioglochina) perkinsiana Alexander, 1930:154.
Holotype ♂. Queensland, Dunk Is., August 25, 1927, F.A. Perkins, QM (T245529).
Studied, photograph Fig. 7.
Figs 7–10. Dicranomyia (Idioglochina) perkinsiana Alexander, holotype ♂: (7)
specimen with labels (QM) and box (AC); (8–10) sketches from holotype slide
1989: (8) antenna; (9) wing tip; (10) part of male terminalia, dorsal.
58 Australian Entomologist
47 (2): 53–72 (2020) 59
According to Alexander (1930) the holotype is preserved in the collection of the
University of Queensland which is now in the Queensland Museum. In 1989,
however, GT found a slide with antenna, wing and terminalia in AC (SI). In 2019
the holotype was found in QM (Fig. 7) with indications in the AC (Fig. 7) it may
have been sent in 1983 from the Smithsonian to E.N. Marks (1918–2002) (J.
Gelhaus pers. comm.). Also in 2019 the slide with antenna, wing and terminalia
was not found in AC (J. Gelhaus pers. comm.). Fortunately, GT had made in 1989
a sketch of what he found signicant on the holotype slide (Figs 8–10). This now
may well be all we have left of the holotype slide.
Description (from Alexander 1930).
Male. Length about 6 mm; wing 7.5 mm.
Rostrum dark brown, nearly as long as the remainder of the head; palpi dark
brown. Antennae dark brown, the rst segment more pruinose; agellar segments
strongly produced beneath, as in the tusitala group, the apical necks short and
stout. Head pale reddish brown, sparsely pruinose, the median region of the
vertex more infuscated.
Mesonotal praescutum with the interspaces brown, the disk with four dark brown
stripes, the lateral and posterior portions of the sclerite dark greyish plumbeous;
pseudosutural foveae punctiform, dark brown; scutum light grey medially, each
lobe with two dark brown areas; scutellum and postnotum light grey. Pleura dark
brownish grey, the dorso-pleural membrane buy. Halteres obscure yellow. Legs
with the coxae dark brown, pruinose, the apices restrictedly pale; remainder of
legs dark brown, the femoral bases only a trie brighter; claws with a series of
about four teeth, the outermost longest. Wings with a strong dusky tinge, Rs and
Cu more suused with still darker brown; veins yellowish brown, some darker
brown. Venation: Sc relatively long, the distance on costa between Sc1 and origin
of Rs about two- thirds the length of the latter; basal section of R4+5 about two-
thirds Rs; R2+3 only gently arcuated; m-cu shortly beyond the fork of M.
Abdominal segments dark brown, the tergites vaguely more reddish brown
medially at base; caudal margins of the segments very restrictedly pale; sternites
obscure brownish yellow, darker laterally, the caudal margins narrowly pale;
hypopygium more brightened. Male hypopygium with the caudal margin of
the ninth tergite with a small but deep V-shaped median notch. Dorsal dististyle
strongly curved, sickle-shaped, narrowed to the subacute apex. Ventral dististyle
with the inner beak-like portion stout, the tip obtuse.
Distribution. Known from the type locality only.
Dicranomyia (Idioglochina) caloundrae sp. n.
(Figs 1, 11–29)
Material Examined. Holotype ♂, Australia, Queensland, Kings Beach, Caloundra,
26°48’12”S 153°08’48”E, 15-vi-2019, leg. A.G. Orr, QM (T246557).
Paratypes, same data as holotype: 3 ♂, 2 ♀, QM (T246558–T246562); 3 ♂, 2 ♀,
Figs 11–13. Dicranomyia (Idioglochina) caloundrae sp. n.: (11) ♂ habitus; (12–13)
male terminalia: (12) dorsal; (13) ventral.
60 Australian Entomologist
Figs 14, 15. Dicranomyia (Idioglochina) caloundrae sp. n.: (14) ♀ habitus with
insert wingtip; (15) female terminalia, lateral.
47 (2): 53–72 (2020) 61
AM (K.393382–K.393386); 1 ♂, 1 ♀, ANIC (29-062219, 29-062220); 2 ♂, AC
(USNMENT01519731–USNMENT01519732) ; 3 ♂, 1 ♀, NMV (T-22489–T-22492);
2 ♂, 1 ♀, GHD (T24683- T24684).
Larvae: 4, GHD (TL1697–TL1700).
Pupae: 11 exuviae, GHD.
Description. Male (Figs 11–13). Body length (excluding antenna) 7.4 mm, wing
Fig. 16. Dicranomyia (Idioglochina) caloundrae sp. n., larvae, habitus.
62 Australian Entomologist
length 9.7 mm.
Head brown, vertex darker greyish brown, antennal scape and pedicel brown,
agellomeres yellowish brown, palpus dark brown. Flagellomeres ventrally
produced, subpectinate, extensions on agellomeres 4–10 more prominent than
on basal or terminal segments. Antenna extending back to prescutal suture.
Pronotum greyish brown. Prescutum, scutum, mediotergite and scutellum greyish
brown, paler golden brown at prescutal pit, centre of transverse suture and
lateral angles of scutal lobes. Pleura pale greyish brown. Coxae greyish brown,
trochanters yellowish brown, femora, tibiae and tarsi greyish brown.
Wing hyaline, veins greyish brown. Distance on costa between Sc1 and origin
of Rs slightly greater than two-thirds length of Rs; basal section of R4+5 one-
half length of Rs; R2 strongly arcuated to bend at angle (as in Fig. 14); m-cu
very slightly proximal to fork of M. Halter with stem yellowish brown and knob
Abdomen with tergites dark brown, sternites yellowish brown. Hypopygium
(Figs 12, 13) largely yellowish brown; posterior border of tergite 9 medially
deeply and widely emarginate, notch semicircular, somewhat deepened in middle,
lobes almost square and bearing abundant stout setae; gonocoxite rather slim,
with rather large rounded mesal lobe; ventral branch of gonostylus with long
apically rounded inner rostrum and strongly developed distinct outer lobe, dorsal
branch slim, pointed and not strongly hooked; aedeagus long, conical, pointed;
parameres long, subtriangular, with tip rounded.
Figs 17–20. Dicranomyia (Idioglochina) caloundrae sp. n., larva: (17–18) head
capsule: (17) dorsal; (18) ventral; (19) mandible; (20) spiracular disk.
47 (2): 53–72 (2020) 63
Male paratypes not diering signicantly from holotype. Distance on costa
between Sc1 and origin of Rs two-thirds to slightly more than whole length of
Rs; basal section of R4+5 one-half to two-thirds length of Rs; R2+3 consistently
strongly arcuated and m-cu slightly proximal to slightly distal to fork of M. Body
length 5.5–7.5 mm. Wing length 7.8–10.0 mm.
Female (Fig. 14) with coloration and wing venation much the same as males, body
length (excluding antenna) 5.0–6.7 mm, wing length 7.0–9.3 mm. Ovipositor
Figs 21, 22. Dicranomyia (Idioglochina) caloundrae sp. n., pupa: (21) respiratory
horn; (22) cauda, lateral view.
64 Australian Entomologist
with cercus slim, almost straight, markedly longer than tergite 10, but shorter
than slim hypogynial valve (Fig. 15).
Larva (Figs 16–20)
Larvae cylindrical, 7.5 mm long. Pale white and smooth (dull pink in life), some
sparse setae present but lacking obvious pubescence (Fig. 16). Dorsal and ventral
creeping welts present on abdominal segments, each bearing minute spines. Head
capsule coloured deep brown anteriorly, paling to golden brown in posterior half
where sclerotisation is weaker, darkening to black in areas of heavy sclerotisation,
particularly above eye spots at apices of the dorsal incisions and ventrally at fusion
of genae and hypostomium (Figs 17, 18). Antenna short, cylindrical, with short
terminal appendage. Clypeus with deep rectangular notch. Labrum a sclerotised
plate, anterior margin shallowly concave, lateral margins rounded. Mandibles 4
toothed, second tooth larger than other teeth, with narrow dorsal ridge and molar
surface minutely crenulate (Fig. 19). Maxilla eshy with dense brush of setae
on medial surface, cardo narrow elongate, palp short with sensilla terminal.
Spiracular disc (Fig. 20) with ve lobes, paired ventral and dorsolateral lobes
short and broad, single dorsomedial lobe narrow and slightly longer. Dorsomedial
lobe with heavy conical sclerite, coloured golden brown, extending from tip of
lobe to centre of spiracular disk, sclerite bearing short tooth near its dorsal edge.
Dorsolateral lobes bearing much weaker sclerites, pale yellow, ovoid, extending
across dorsal 1/3 of lobe. Ventral lobes with similar weak yellow sclerites,
broadly triangular and positioned in centre of lobes. Each spiracular lobe with
Figs 23–30. Dicranomyia (Idioglochina) spp., key characters. 23–24: D. (I.)
australiensis; (23) wing tip, (24) abdomen, ventral. 25–27: D. (I.) perkinsiana; (25)
wing tip, (26) wing tip, (27) male terminalia, dorsal. 28–30: D. (I.) caloundrae sp.
n.; (28) wing tip, (29) male terminalia, ventral, (30) male terminalia, dorsal.
47 (2): 53–72 (2020) 65
apical fringe of short setae, ventral and dorsolateral lobes each bearing single long
thick seta. Spiracles in centre of disk, of moderate size, ovoid. Terminal segment
ventrally bearing four short globose anal papillae.
Pupa (Figs 21, 22)
General form elongate cylindrical, integument primarily smooth with ve
dorsal and ventral creeping welts present on abdominal segments, each bearing
minute spines. Head, thorax and wing pads brown to dark brown, abdomen pale.
Respiratory horns (Fig. 21) greatly developed, eshy, with broad base dividing into
three branches, each branch with numerous digitate projections. Central branch of
respiratory horn consistently longer than lateral branches and generally equal to
length of mesonotum. Number, length and placement of digitate processes vary
23 25 28
24 27 30
66 Australian Entomologist
greatly between individuals. Wing pads not extending beyond rst abdominal
welt. Leg sheaths of equal length and not exceeding second abdominal welt. Cauda
(Fig. 22) heavily sclerotised, bearing multiple rounded to low spinous lateral and
ventral projections and two prominent dorsally curved hooklike projections.
Discussion. The adult of D. (I.) caloundrae (Figs 11–15) is very similar to both
Australian species D. (I.) australiensis (Figs 2–6) and D. (I.) perkinsiana (Figs
7–10).The large size (male body 5.5–7.5 mm, wing 7.8–10.0 mm, female body
5.0–6.7 mm, wing 7.0–9.3 mm) clearly distinguishes it from D. (I.) australiensis
(male body 4.5 mm, wing 4.8 mm, female body 4.5 mm, wing 5 mm). In addition,
the aedeagus appears longer and more acutely pointed in male D. (I.) caloundrae
(Figs 12, 13) than in D. (I.) australiensis (Fig. 6). A stronger arcuated R2 on
the wingtip, the male terminalia with a wide, generally semicircular medially
slightly deepened median notch of tergite 9, the outer portion of the ventral
gonostylus narrowly produced and the dorsal gonostylus less strongly hooked
(Fig. 12) distinguish it from the equally large D. (I.) perkinsiana in which R2 on
the wingtip is only gently arcuated and in the male the median notch of tergite
9 is narrowly V-shaped, the outer portion of the ventral gonostylus not narrowly
produced and the dorsal gonostylus more strongly hooked (Fig. 10).
Saunders (1928) provided the rst account of the immature forms of Dicranomyia
(Idioglochina), describing the larva and pupa of D. (I.) signipennis Coquillett,
1905, collected from marine algal growth on Newcastle Island, Vancouver,
Canada. Alexander (1949) synonymised D. (I.) signipennis with D. (I.) marmorata
Osten Sacken, 1861, which is distributed along the west coast of North America
to California. Tokunaga (1939) then provided a description of the larva of D. (I.)
gloriosa Tokunaga, 1938, found amongst marine algae on the shore of Sagami bay,
Kanagawa, Japan. The descriptions by Saunders and Tokunaga provide the only
points of comparison for the larvae of D. (I.) caloundrae, as no other descriptions
of larval Dicranomyia (Idioglochina) seem to be available. Additional details of
the pupa of D. (I.) marmorata were provided by Ring (1978) and included a
thorough examination of the respiratory horns. The larvae of D. (I.) caloundrae
were found living in marine algae, like the larvae of D. (I.) marmorata and D. (I.)
gloriosa, and larvae are similar in general form. D. (I.) caloundrae seems more
similar to D. (I.) gloriosa than to D. (I.) marmorata and the three species are
readily distinguished by the features of the spiracular disk. D. (I.) marmorata
possesses a spiracular disk with only 4 lobes, while both D. (I.) gloriosa and
D. (I.) caloundrae possess a fth dorsomedial lobe. In D. (I.) caloundrae the
sclerite of the dorsomedial lobe bears a prominent tooth, while in D. (I.) gloriosa
this sclerite lacks teeth or spines. No other Australian limoniid larvae are
known to possess a spiracular disc with a conical sclerite bearing a tooth, and
this feature readily distinguishes the larva of D. (I.) caloundrae from any other
known Australian larvae. The pupae of D. (I.) caloundrae are generally similar
to those of D. (I.) marmorata diering most noticeably in the development of
the respiratory horn. In D. (I.) marmorata the respiratory horn has a single eshy
branch arising from a broad base, both lacking digitate processes, while in D. (I.)
Figs 31, 32. (31) habitat of Dicranomyia (Idioglochina) caloundrae sp. n. looking
west in mid-afternoon; (32) a male perched in sunlight low on a boulder awaiting
females with which to mate.
47 (2): 53–72 (2020) 67
68 Australian Entomologist
caloundrae three branches arise from the base of the respiratory horn, all bearing
numerous digitate processes. The only other Australian pupae known to possess
a multibranched respiratory horn are those of the genus Antocha Osten Sacken,
1861, however the number of branches is greater than in D. (I.) caloundrae and
the branches do not bear digitate processes. Thus the structure of the respiratory
horn easily distinguishes the pupa of D. (I.) caloundrae from any other known
Australian limoniid pupae.
It should be pointed out that the species name D. gloriosa mentioned above
in the discussion, turned out to be preoccupied and was replaced by the name
D. tokunagana Alexander, 1964.
Etymology. Caloundrae is a toponym (noun in genitive case) referring to the type
locality of the species near Caloundra in south-eastern Queensland.
Key to the males of Australian Dicranomyia (Idioglochina)
1 Small species, wing length approximately 5 mm; R2 long and strongly
arcuated (Fig. 23); aedeagus blunt (Fig. 24); from Torres Strait, northern
Larger species, wing length 7–10 mm; R2 short and gently arcuated
(Figs 25, 26) or long and strongly arcuated (Fig. 28); aedeagus
pointed (Figs 27, 29); from eastern Australia................................................2
2 R2 short and gently arcuated (Figs 25, 26); tergite 9 of male with
narrow V- or U-shaped posteromedial notch (Fig. 27); from tropical
R2 long and strongly arcuated (Fig. 28); tergite 9 of male with wide,
generally semicircular, posteromedial notch (Fig. 30); from sub-
tropical eastern Australia....................................................caloundrae sp. n.
Habitat: Adults were found ying and perching in the lower intertidal zone.
Although occasional specimens are seen around most rocky shores exposed to the
ocean in the neighbourhood, the type locality, along about 200 m of shoreline, is
distinguished by the way the rock shelf curves to face WSW, and is thus protected
from most direct wave action from the Pacic Ocean. As a result of the calm
conditions there has developed a broad expanse of shallow rock platform with low
boulders supporting a rich growth of numerous types of marine algae, hard and
soft corals and sponges which is exposed at low tide (Fig. 31). Adults are active
in large numbers at low spring tides mainly along this favourable strip, usually
within 20 m of the extreme low tide mark. The favoured breeding habitat appears
to be thick encrusting mixed green and coralline algal mats on the top of low
boulders. It was from these situations adults were seen emerging with the pupa
embedded in the algal mat (Fig. 33). Young larvae were discovered in pure stands
of pink Corallina alga growing lower in rock pools but only in small numbers and
no mature larvae were recovered. Other marine Diptera present were one species
each of Clunio Haliday and ?Telmatogeton Schiner (both Chironomidae). The
Figs 33–36. Dicranomyia (Idioglochina) caloundrae sp. n. adults, clockwise
from top left: (33) a female emerging from pupa in algal mat; (34) adult resting
under rock ledge; (35) adult perched in sunlight; (36) a female on top of an algal
encrusted rock seeking an oviposition site.
47 (2): 53–72 (2020) 69
former were extremely numerous and their larvae dominated the Corallina beds.
Phenology: Daily counts were made for 41 days from June 26th to August 5th,
covering one full lunar cycle from new moon to new moon. The tidal pattern
is semidiurnal (i.e. two low and two high tides each 24 hours). Observations
were made at the diurnal low tide, at that time of year the lowest tide of the day.
On one day (22/7/2019) both low tides took place in twilight and no records
70 Australian Entomologist
were made. The results (Fig. 37) show a strong association with emergence and
reproductive activity associated with lunar phases, with large numbers being
present for 4 or 5 days around new moon and full moon. In this data set the
lunar phase seemed more important in triggering emergence than tide level.
Protandry was pronounced, with almost only males sampled on the rst day of
mass emergence. By the second day numerous teneral females were present as
well as males with hardened bodies. Matings were observed. The following day
oviposition began and numbers remained high for two or three more days, after
which they disappeared. However the pattern of emergence varies seasonally, as
has been shown for Clunio tsushimensis Tokunaga in the Sea of Japan (Saigusa
& Akiyama 1995), where the tidal cycles are quite similar to Caloundra, with the
lowest daily tide becoming nocturnal later in the year. Supporting this was the
observation that no D. (I.) caloundrae were seen at a diurnal low tide of 0.04 m at
new moon on 30/8/2019, about the time when the lower of the two daily low tides
shifted to the night, and relatively few (15) were recorded on a standard transect
walk at low tide (0.33 m) on the following full moon (14/9/2019). Both days
oered perfect weather conditions. On 26–27/10/2019 (new moon) great numbers
were observed near the nocturnal low tide just after midnight, whereas none were
observed on the diurnal low, despite the tide falling to 0.23m. On 10–12/11/2019
and 10–12/12/2019 (full moon) the same pattern occurred. On 25–26/11/2019
(new moon) very large numbers were present at night, whereas only a small
number were active (5 detected on a standard transect walk) during the diurnal
low (0.33m). At night the insects were detected by illuminating the main habitat
with car headlights. It was not possible to establish counts comparable with the
diurnal observations shown in Fig. 37, but the general impression was that peak
numbers were similar. These observations further indicate that emergence and
activity are not linked to the absolute level of the low tide, but are synchronised
to the lower of the two tides each day around full and new moon.
Behaviour: Adults were observed on the wing, mating and ovipositing. Sometimes
they rested on algal mats on boulders in sunlight, especially on windy days, and
occasionally under rock ledges (Figs 32, 34–36). They were active even on dull
days and in light rain. Females especially were observed emerging from their
pupae embedded in algal mats (Fig. 33) and on three recorded occasions a male
stood over the emerging female and mated with her once she emerged. On another
occasion, two males contested possession of an emerging female and a ght
ensued with both ying out of sight and the female emerged unhindered. Most
matings probably took place when males located post teneral females. Oviposition
was observed frequently. The female would perch on top of an algal mat on a low
boulder, often washed by waves, and rapidly bob up and down as she inserted
her ovipositor into the substrate in quick short stabs. Sometimes a male would
stand over her, almost certainly a case of mate guarding, and on six occasions
determined eorts were made by a second and twice by a third male to displace
the guarding male, none of which were successful although two struggles resulted
in all three males ying o leaving the female unguarded. Attempted mating with
Fig. 37. Phenology of appearance of Dicranomyia (Idioglochina) caloundrae sp. n.
adults (red line, relative abundance scale left abscissa) and lowest daily tide (blue line,
tide level scale right abscissa) from 26/6/2019–5/8/2019; lunar phase indicated above.
47 (2): 53–72 (2020) 71
ovipositing females was observed several times but was never successful.
John Martin (AM) and Geo Thompson (QM) supplied photographs. J. Gelhaus
(Philadelphia), S. Podenas (Vilnius), and Karin Koch (QM), tried to locate type
specimens. J. Gelhaus, P. Oosterbroek (Amsterdam) and J. Stary (Olomouc) gave
valuable suggestions improving the manuscript.
The map provided in Fig. 1 is modied from SIO, NOAA, U.S. Navy, NGA,
GEBCO map data, created using Google Earth Pro for desktop, © Google 2019.
ALEXANDER, C.P. 1921. New species of crane-ies from North Queensland (Tipulidae, Diptera).
Canadian Entomologist 53: 205–211.
ALEXANDER, C.P. 1922. New or little-known species of Australian Tipulidae (Diptera). I.
Proceedings of the Linnean Society of New South Wales 47: 581–590.
ALEXANDER, C.P. 1928. New or little-known Tipulidae from the Philippines (Diptera). V.
Philippine Journal of Science 40: 239–272.
ALEXANDER, C.P. 1930. New or little-known Tipulidae (Diptera). XLIV. Australasian species.
Annals and Magazine of Natural History (10) 5: 136–156.
ALEXANDER, C.P. 1949. Records and descriptions of North American crane-ies (Diptera). Part
VIII. The Tipuloidea of Washington. I. American Midland Naturalist 42: 257–333.
ALEXANDER, C.P. 1964. New or little-known Tipulidae from eastern Asia (Diptera). LIV.
Philippine Journal of Science 93: 277–324.
72 Australian Entomologist
ALEXANDER, C.P. 1972. Diptera: Tipulidae. Insects of Micronesia 12: 733–863.
COQUILLETT, D.W. 1905. New nematocerous Diptera from North America. Journal of the New
York Entomological Society 13: 56–69.
COQUILLETT, D.W. 1910.The type-species of the North American genera of Diptera. Proceedings
of the United States National Museum 37: 499–647.
McALPINE. J.F. 1981. Chapter 2. Morphology and Terminology—Adults. Pp. 9–63, in: McAlpine,
J.F., Peterson, B.V., Shewell, G.E., et al. (eds), Manual of Nearctic Diptera, volume I. Research
Branch Agriculture Canada Monograph No. 27. Canadian Government Publishing Centre. Ottawa.
MEIGEN, J.W. 1818. Systematische Beschreibung der bekannten europäischen zweiügeligen
Insekten. Erster Theil. F.W. Forstmann, Aachen; xxxvi + 332+  pp.
OOSTERBROEK, P. 2019. Catalogue of the craneies of the World (CCW). Available online at ccw.
OSTEN SACKEN, C.R. 1861. Description of nine new North American Limnobiaceae. Proceedings
of the Academy of Natural Sciences of Philadelphia 1861: 287–292.
RING, R.A. 1978. Spiracular gills of the pupa of the intertidal crane y, Limonia (Idioglochina)
marmorata (Diptera: Tipulidae). Canadian Entomologist 110: 1277–1280.
SAIGUSA, M. and AKIYAMA, T. 1995. The tidal rhythm of emergence, and the seasonal variation
of this synchrony, in an intertidal midge. Biological Bulletin 188: 166–178.
SAUNDERS, L.G. 1928. Some marine insects of the Pacic coast of Canada. Annals of the
Entomological Society of America 21: 521–545.
STEPHENS, J.F. 1829. A systematic catalogue of British insects, being an attempt to arrange all
the hitherto discovered indigenous insects in accordance with their natural anities. Containing also
the references to every English writer on entomology, and on the principal foreign authors. With all
the published British genera to the present time. Part II. Insecta Haustellata. Baldwin & Craddock,
London; 388 pp.
THEISCHINGER, G. 1996. The Limoniinae (Diptera: Tipulidae) of Australia. VIII. Preliminary key
to the genus-group taxa. Stapa 44: 117–144.
TOKU NAG A, M. 1938. A new marine crane-y from Japan. Annotationes Zoologicae Japonenses
TOKU NAG A, M. 1939. Female and larva of the marine craney Limonia (Idioglochina) gloriosa
Tokunaga. Annotationes Zoologicae Japonenses 18: 101–104.