Journal of
Threatened Taxa | www.threatenedtaxa.org | 26 July 2018 | 10(8): 12035–12043
Taxonomic status and additional description of White’s Stalked-eyed Fly Cyrtodiopsis whitei (Curran, 1936) (Diptera: Diopsidae) from India
with a key to the allied species and note on its habitat
Basant Kumar Agarwala
Department of Zoology, Tripura University,
Suryamaninagar, Bikramnagar,
Tripura 799022, India
bagarwala00@gmail.com
Abstract: Systematics and ecology of Cyrtodiopsis whitei (Curran,
1936), initially described in brief from a tropical dry deciduous
forest in eastern India as Diopsis whitei, remained obscure for want of the type
specimens. Recent collections of male and female specimens of this
species from a new locality in the northeastern
part of India, the country of the type locality, has allowed a fresh appraisal
of its morphology, taxonomic position and habitat ecology in the background of
several studies done on Diopsidae. Herein are
included some new characters, hitherto unknown in the species of Cyrtodiopsis, a taxonomic key to the separation of
four species, considered monophyletic under the genus, and a note on the
habitat of the species.
Keywords: Cyrtodiopsis,
Diopsis, habitat, monophyletic, new characters,
systematics, taxonomic key.
doi: http://doi.org/10.11609/jott.3272.10.8.12035-12043 | ZooBank:
urn:lsid:zoobank.org:pub:5D25C79A-A3F6-46FA-A302-5BC3B013C713
Editor: Mihaly Foldvari,
University of Debrecen, Hungary. Date of
publication: 26 July 2018 (online & print)
Manuscript details: Ms # 3272 |
Received 06 January 2017 | Final received 12 May 2018 | Finally accepted 20
June 2018
Citation: Agarwala, B.K. (2018). Taxonomic status and additional description of White’s
Stalked-eyed Fly Cyrtodiopsis whitei (Curran, 1936) (Diptera:
Diopsidae) from India with a key to the allied
species and note on its habitat. Journal of Threatened Taxa 10(8): 12035–12043; http://doi.org/10.11609/jott.3272.10.8.12035-12043
Copyright: © Agarwala 2018. Creative Commons Attribution 4.0
International License. JoTT allows
unrestricted use of this article in any medium, reproduction and distribution
by providing adequate credit to the authors and the source of publication.
Funding: This study was supported by Indian Council of Agriculture Research, New Delhi through a project no. F. No.16-16/2007-IA
IV to the author.
Competing interests: The author declares no competing interests.
Author Details: Basant Kumar Agarwala
is a full Professor in the Department of Zoology at Tripura University,
Tripura, India. His research interests comprise of systematic, ecology and
diversity of insects of northeastern India.
Acknowledgements:
The author is thankful to Dipankar
Kishore Sinha for his tireless help in the field and
in the drawing of some of the figures. Gratitude is extended to the subject
editor for several improvements in the original manuscript.
INTRODUCTION
Worldwide,
Stalked-eyed Flies of the family Diopsidae Bilberg, 1820 are known by 189 species from 12 genera (Roskov et al. 2015).
These include reports of eight species in five genera from India (Mitra et al. 2014).
Baker et al. (2001), Meier & Baker (2002), and Földvári
et al. (2007) considered species of Teleopsis
Rondani, 1875 and Cyrtodiopsis
Frey, 1928 to be congeneric based on molecular affinity provided by partial
nucleotides alignments of three mitochondrial and three nuclear genes. Feijen (2011),
however, disputed the single clade phylogenetic hypothesis by Baker et al.
(2001) and preferred Teleopsis and Cyrtodiopsis to be paraphyletic and that is being
widely followed in diopsid taxonomy and biology till
date (Roskov et al. 2015).
The
original description of Cyrtodiopsis whitei under the genus Diopsis
by Curran from India in 1936 had inadequate morphometrical
details and illustrations of diagnostic characters. The whereabouts of the type specimens (male holotype and a female allotype)
collected on 2 May 1935 and originally deposited in the American Museum of
Natural History (New York) is uncertain, and Shillito
(1940) based his study of the species on a single specimen by the identical
name collected on 21 October 1920 from a location in ‘Jungle of Assam’, northeastern India. Földvári et al. (2007), based on laboratory culture
specimens from Malaysia, provided another brief description of the species
without sufficient illustration of diagnostic characters, and without reference
to the original description provided by Curran (1936). It is, therefore, doubtful if the Malaysian
specimens are really C. whitei. Extensive uses of laboratory-reared C. whitei in behavioral (Lorch et al. 1993; Wilkinson et al. 1998; Al-Khairulla et al. 2003), physiological (Burkhardt
& de la Motte 1983; Buschbeck
& Hoy 2005) and genetic studies (Wilkinson et al. 1997; Wilkinson &
Sanchez 2001) has made this species name well known as an experimental object
for molecular and behavioral studies of stalked-eyed
flies in general.
Therefore,
in view of the recent collection of both the sexes of C. whitei
from a new location in northeastern India, the
country of the type locality, it became necessary to provide accurate
description of the species based on biometric data and supported by photographs
and line drawings which include descriptions of new morphological characters
previously unnoticed in this species.
Another objective of this study is to provide a better understanding of C.
whitei in its area of distribution and its
relation to other species so as to ensure its accurate identification and a
better taxonomic appraisal of the genus.
To that end, an identification key to the known species of Cyrtodiopsis, sensu Feijen (2011), and a note on the habitat have also been provided.
METHODS AND
MATERIALS
Live
specimens of C. whitei were collected from the
wild habitat using insect nets and these were transferred to killing jars. Biotic and abiotic features of the habitat of
occurrence were recorded on each occasion of specimen collection. Dead and dry specimens were brought to the
laboratory and kept in relaxation boxes for 36 hours to allow softening of
external parts. Individual insects were spread
to their natural posture and mounted on paper tips, pinned, labeled,
and studied under Leica M205C zoom stereoscopic microscope fitted with Leica
DFC295 digital camera. Biometry to the
accuracy of 0.01mm and microphotographs were taken using Leica Application
3.8.0 version software. Images, so
acquired, were transferred in Microsoft power point slides to write the names
of characters. Abdomens of six males and
a female were dissected for genitalia study.
These were individually subjected to heating in glass vials at 600C,
first in 10% KOH solutions for 10 minutes for maceration, then for five minutes
each at increasing concentrations of ethyl alcohol (70%, 80%, 90% and 99.99%)
for dehydration. Dehydrated specimens
were boiled for five minutes in the saturated solution of choral phenol for
softening of cuticle and sclerotised structures (Feijen & Feijen 2011). Finally, the abdomens with the ventral side
up were mounted individually on clean glass slides with the help of fine tip
needles under the Carl Zeiss Stemi 2000-C microscope
and studied under Carl Zeiss AXIO Lab.1 microscope under 10X and 40X objectives
and for Camera Lucida drawings.
Specimens of this study are deposited with identical accession numbers,
as used in Tables 1 and 2, in the Insect Biodiversity Laboratory, Department of
Zoology of Tripura University.
RESULTS
Order Diptera
Infra order Muscomorpha
Super family Diopsoidea
Family Diopsidae
Bilberg, 1820
Genus Cyrtodiopsis
Frey, 1928
Diagnosis:
Thorax with a pair of infra-alar spines, supra-alar spines absent, scutellar spines slightly to strongly curved outward,
hairy, and each spine with a terminal bristle; fore femora conspicuously
constricted on inner side at apex with incrassate surface; a tubercle is
present at the base of inner margins of fore tibia that seems to fit into the
constricted apex of fore femora when the fly is in rest.
Taxonomic
status of the genus: Frey (1928) proposed Cyrtodiopsis
from a collection of the Stalk-eyed Flies of Philippines on the basis of a
distinct “peg and hollow structure of forelegs in certain males” with dalmanni (Weidmann) as the
type species. Shillito
(1940) provided the first illustrated account of the family with a key to the
identification of eight genera with particular reference to five species of the
genus Cyrtodiopsis. Shillito (1940)
distinguished Cyrtodiopsis from its nearest
taxonomic relative Teleopsis in the wings
without an alula, the thorax with infra-alar spines but without supra-alar
spines, scutellar spines strongly curved, hairy and
with a terminal long bristle and, most important, fore femora with constricted
apex ventrally and fore tibia with rounded tubercles present at the base of the
ventral side. Földvári
et al. (2007) added a new species Teleopsis thaii, which is considered to be a Cyrtodiopsis species in the present work.
Cyrtodiopsis whitei (Curran, 1936) (Images 1–5; Figs. 1–5)
= Diopsis whitei
Curran, 1936, Am. Mus. Nov. 833: 1–2
= Teleopsis whitei
(Curran, 1936) in Földvári, M., A. Pomiankowski, S. Cotton & M. Carr (2007) Zootaxa 1620: 37–51.
Materials
examined: TU/Dipt/Diop-4004, TU/Dipt/Diop-4005,
TU/Dipt/Diop-4006, 3 males, 12.viii.2013, Sakaibari, Dhalai District,
Tripura, 24.109950N & 91.908880E, decomposing organic
mass floating in shallow waters of Gomti; TU/Dipt/Diop-4007, TU/Dipt/Diop-4008,
TU/Dipt/Diop-4009, 3 males and 1 female, 30.vii.2015,
coll. D.K. Sinha.
Habitat:
The habitat of C. whitei in the Dhalai District of Tripura province is an evergreen primary
virgin forest of low hills of ‘Longtharai’ (local
name meaning ‘deep valley’) and is the catchment area of two rivers, each of
which traverses through valleys forming wide and narrow to very narrow streams
lined by rocky banks and verticals.
Stalk-eyed flies were found to be active in the sunshine hours in
decomposing mixed vegetation dominated with banana leaves that was either
floating in streams or in organic mass formed near the bank of stream. Atmospheric temperature and humidity of the
habitat at the collection sites were recorded to be 24.2–25.6 0C and
74–77 %, respectively, and that of the microhabitat within 10cm of aerial
distance of the collection points were found to be 21.4–22.8 0C and
81–84 %, respectively.
Description of additional characters
Male:
Length 4.56–5.69 mm; coloration generally brownish, head with antennae
yellowish-brown to brown, thorax shining brown, scutellum
darker than pre-scutellum or scutum;
coxae and femora reddish-brown, tibiae and bases of
tarsi reddish-brown to deep brown; wings pale brown with outer margins dark;
abdomen with basal three segments pale brown and distal segments dark brown
(Image 1). Head (Images 2,3; Fig. 1 ): sub-triangular, dorsum of central part yellowish brown
(Image 2), conspicuously raised and bears three ocelli,
one bigger in the front and two smaller on sides, with a pair of deep brown
bristles having pointed apices (Fig. 1), about 0.14–0.18 mm long; frons
brownish, humped, projected forward, with a dorsal curved deep brown band and a
distinct mid-suture, face concolorous with dorsum of
head, slightly protruding, bear several long blackish bristles with pointed
apices, 1–2 of these with bifid apices, about 0.20–0.24 mm long; vertex
yellowish brown to brown, narrower in front, broader at base and with rounded
edges, bearing long hairs of bifid apices on the posterior edges (Image 3a);
eye stalks yellowish-brown, smooth, bears a row of sparse, thin hairs, facing
outward, with pointed apices, curved gently to strongly, these gradually
decrease in lengths from the origin of stalks in the central part of the head
to the bases of antennae (Image 2), the longest ones at the base of eye stalk
0.12–0.14 mm long, 0.07–0.0.10 mm long in the middle of eye stalks, and
0.06–0.0.08 mm long at the bases of antennae, thus the longest ones at the base
of eye stalk, on average, are 1.50–2.33 times longer than the shortest ones
near the base of antenna; inner vertical bristles (IVB) and outer vertical
bristles (OVB) at low tubercles, 0.51–0.66 mm and 0.25–0.37 mm long,
respectively (Table 1), and these 4.31–5.90 times and 2.10–3.38 times the
middle width of eye stalks, respectively (Table 2); eye span 3.98–7.52 mm long
and 0.87–1.32 times the body length; antennae light brown, 3-segmented (Image 2),
0.32–0.36 mm long, the shortest basal segment with a dark bristle on inner
side, called scape, 0.07–0.10 mm long, the middle segment, called pedicel,
0.15–0.19 mm long (Table 1) and about 2–3 times longer than the basal segment
(Table 2), bear 2–3 dark bristles, and the third and last segment, called first
flagellomere, nearly bulbous, densely covered with
small hairs, 0.09–0.12 mm long, about twice the length of the middle segment,
and bears a thick, long bristle-like structure with pointed apex on a raised
base, called arista (Fig. 2), 0.70–0.90 mm long (Table 1), and 1.30–1.52 times
and 1.89–2.57 times the lengths of IVB and OVB, respectively (Table 2). Thorax (Image 3): collar glossy brown,
V-shaped, scutum glossy brown, bi-lobed, smooth; scutellum shorter than wide, 0.18–0.25 mm long and
0.44–0.61 mm wide, with dorsum broad, glossy brown, densely pollinose
in the centre of pronotum and mesonotum
(Image 3b), bears many short thin hairs with pointed apices only and a few long
and prominent hairs with pointed or bifid apices, the longest ones about
0.25–0.39 mm long; infra-alar spines yellowish, short, dorso-ventrally
flattened, and with blunt apices (Image 3c), these about 0.24–0.32 mm long
(Table 1); scutellar spines dark, slightly curved
inward, 0.69–1.12 mm long, 3.75–4.73 times the length of scutellum,
each spine bears on its inner side 2–3 small hairs with pointed apices and 3–4
longer hairs with bifid apices (Image 3d), the longest ones about 0.26–0.35 mm
long, and a long apical bristle, about 0.44–0.49 mm long (Table 1). Wings (Image 4): 3.16–4.30 mm long, bases of
fore wings leathery, rest membranous, dorsal surface densely covered with
minute hairs; four distinct pale brown to brown bands present from base to the
apex, the basal-most band paler than the other three bands, covers anal cell, discal cell, radial cell and subcostal-radial cell from
lower to upper parts of the wing; the second band from the wing base broadest
and darkest between R2+3 and R4+5, and pale between costa
and R1; the sub-apical third band brownish, irregular, widest in the
middle or radial-medial cell, and the fourth apical-most band narrowest, pale
brown to brown in different specimens, extending from R2+3 to M1+2
from the apex and projects slightly to prominently towards the subapical band in the median cell; subapical
and apical bands separated by three pale spots from apex to base of wings, with
the median semi-circular hazy spot in comparison to pale but distinct anterior
and posterior circular spots; hind wings leathery, stump-like with a short
stalk and attached to the raised bases.
Legs: conspicuously hairy, longer hairs with bifid apices; fore coxae 0.78– 0.85 mm long, swollen in the middle; fore
femora much wider (0.33–0.37 mm) than mid- (0.13–0.16 mm) and hind femora
(0.10–0.12 mm), basal ¼ part of inner margins smooth, rest ¾ margins
incrassate, with a shallow constriction near the joint with tibia (Image 5);
fore tibia with a low, rounded and dark tubercle in the apex that seems to fit
in the constricted part of the fore femur on each side when the fly is in rest;
tibiae dark, sparsely hairy on margins; tarsi 5-segmented, first segment the
darkest and the longest, 0.66–0.74 mm long, densely hairy on posterior margins,
next four segments paler, decreasingly smaller in sizes, the apical-most
segment the smallest, 0.10–0.12 mm long, about 6.16–7.20 times the first tarsal
segment, bear two dark, curved divergent claws.
Abdomen black, clavate shaped (Image 1), first
three segments fused, fuscus, with sparse long and
thin hairs having pointed apices, tergites mildly pollinose, fourth, fifth and sixth segments with distinct
inter-segmental sutures, wider than first three segments, gently deflexed
ventrally, tergites and pleurites
with hairs all over, segments 7 to 10 narrow to very narrow, condensed, covered
with microtrichia and a few sparsely distributed long
hairs; sub-anal plate triangular, heart-shaped; cerci club-shaped, apically
rounded, about twice the length at base.
Genitalia (Figs. 3–5): In ventral view, epandrium
rounded with sclerotised and smooth margins, with 18
pairs of long setae counted when mounted in slide; surstyli
pale, broad basally with thin margins but brown, bulbous apically, bulbous ends
sclerotised and proximate in the middle, covered with
microtrichia, with four pairs of long setae, two
pairs originate from the inner margins of the base and other two pairs
originate from the outer margins of bulbous apex (Fig. 3); cerci large, with
broad base and nearly conical apices, about twice as long as broad at the base,
with thin margins and five pairs of hairs, two pairs of smaller hairs projected
outwards and three pairs of longer ones projected inwards; hypandrium
flat brown, with smooth margins, hypandrial bridge glabrous, in ventral view smooth, pale brown, bridge brown,
with rough surface (Fig. 4); aedeagal apodeme elongated, brown, connected basally to hypandrium, in lateral view aedeagus
with somewhat rounded end, sclerotic, and with a well developed ejaculatory apodeme (Fig. 5).
Female:
The single female in the collection is similar to males except in longer body
(6.49mm), longer OVB (0.39mm), longer antennae (0.43mm), longer hairs on head
and eye stalks (Table 1), longer scutellum (0.32mm)
and scutellar spines (1.12mm), fore coxae, fore femora and wings (Table 1). Genitalia parts were damaged in course of
slide mounting.
Taxonomic
status: Curran (1936) described Diopsis whitei from a tropical dry deciduous forest in
Jharkhand in eastern India. That
description lacked illustrations or drawings of distinguishing characters of
the species. Shillito
(1940) transferred the species to Cyrtodiopsis
because of the presence of characteristic apical incrassate constriction infore femora and low rounded tubercles in the fore
tibia. Since then six males and one
female specimen of this species from a tropical evergreen forest in northeastern parts of India have become available from the
country of its type locality. These show
strong similarities with C. whitei in the
structure of wings, the pollinose pattern of the scutellum, and general description of body parts sensu Curran (1936) and Shillito
(1940). Hans Feijen
(pers. comm. 10.07.2015) found our specimens to show similarity with the single
C. whitei specimen in his possession from
Meghalaya in northeastern India. Detail examination of specimens used in this
study, however, warranted description of new characters not described earlier;
these include some of the hairs present on dorsal surfaces of head, thorax, scutellar spines and on femora and tibiae with bifid
apices, presence of a row of progressively gently to strongly curved frontal
hairs of decreasing lengths from the base of the eyestalk to the base of
antenna, and in the structure of male genitalia which were not adequately
described. None of existing literature
on Diopsidae mention the
occurrence of hairs with bifid apices and curved frontal hairs of eye stalks
that were noted in specimens of C. whitei of
this study. It is possible that earlier
workers might have missed these characters in whitei
or other taxa of Diopsidae, therefore, it may be
premature to conclude that these characters are unique to C. whitei or that the sample of this study might represent
a new population of a distinct species.
The author was not able to access the type specimens of whitei or specimens of other species of Diopsidae from valid sources. Therefore, at this point, the specimens of
this study from moist evergreen forests of northeastern
India are considered to represent possibly a part of widely distributed
populations of whitei complex in its
geographic range extending from the dry deciduous forest of eastern India
(Jharkhand, the type locality) to moist evergreen forest in northeastern
India, and, possibly, further east in Southeast Asia (Malaysia included), and
it is assumed that populations of whitei might
show habitat/area-specific variations and this position may be maintained until
such time future study reveals more information.
Table 1. Morphometry*
of C. whitei**
|
Characters |
Male 1 (4004) |
Male 2 (4005) |
Male 3 (4006) |
Male 4 (4007) |
Male 5 (4008) |
Male 6 (4009) |
Range (min.–max.) |
Female 1 (4010) |
|
Body length |
5.58 |
5.69 |
5.12 |
5.59 |
5.34 |
4.56 |
4.56–5.69 |
6.49 |
|
Eye span |
6.95 |
7.52 |
4.95 |
6.57 |
5.72 |
3.98 |
3.98–7.52 |
5.83 |
|
Eye stalk length |
3.47 |
3.71 |
2.47 |
3.29 |
2.81 |
1.99 |
2.47–3.71 |
3.03 |
|
Eye stalk middle width |
0.13 |
0.14 |
0.10 |
0.13 |
0.12 |
0.12 |
0.10–0.14 |
0.13 |
|
Inner vertical bristle |
0.58 |
0.66 |
0.59 |
0.62 |
0.51 |
0.54 |
0.51–0.66 |
0.64 |
|
Outer vertical bristle |
0.37 |
0.37 |
0.35 |
0.37 |
0.25 |
0.32 |
0.25–0.39 |
0.39 |
|
Antenna 1st segment |
0.10 |
0.07 |
0.08 |
0.08 |
0.08 |
0.07 |
007–0.10 |
0.09 |
|
Antenna 2nd Segment |
0.15 |
0.15 |
0.19 |
0.16 |
broken |
0.16 |
0.15–0.20 |
0.20 |
|
Antenna 3rd Segment |
0.09 |
0.10 |
0.09 |
0.10 |
broken |
0.12 |
0.09–0.14 |
0.14 |
|
Antenna length |
0.34 |
0.32 |
0.36 |
0.34 |
broken |
0.35 |
0.32–0.43 |
0.43 |
|
Arista length |
0.82 |
0.70 |
0.90 |
0.81 |
broken |
0.74 |
0.70–0.90 |
0.82 |
|
Longest hair: head dorsum with bifid
apices |
0.18 |
0.125 |
0.15 |
0.18 |
0.10 |
0.13 |
0.10–0.23 |
0.23 |
|
Longest hair: base of eye stalk |
0.14 |
0.14 |
0.12 |
0.14 |
0.12 |
0.12 |
0.12–0.16 |
0.16 |
|
Longest hair: near IVB |
0.07 |
0.10 |
0.08 |
0.10 |
0.10 |
0.08 |
0.07–0.10 |
0.10 |
|
Longest hair: near antennal base |
0.07 |
0.07 |
0.08 |
0.06 |
0.08 |
0.08 |
0.06–0.08 |
0.06 |
|
Longest hair: thorax dorsum |
0.32 |
0.38 |
0.27 |
0.33 |
0.28 |
0.25 |
0.27–0.39 |
0.39 |
|
Scutellum length |
0.23 |
0.23 |
0.18 |
0.25 |
0.23 |
0.18 |
0.18–0.32 |
0.32 |
|
Scutellum width |
0.57 |
0.61 |
0.48 |
0.55 |
0.48 |
0.44 |
0.44–0.61 |
0.61 |
|
Infra-alar spine length |
0.29 |
0.31 |
0.25 |
0.32 |
0.29 |
0.24 |
0.24–0.35 |
0.35 |
|
Scutellar spine length |
1.02 |
1.08 |
0.80 |
1.0 |
0.99 |
0.69 |
0.69–1.12 |
1.12 |
|
Longest hair: scutellar
spine |
0.30 |
0.35 |
0.28 |
0.32 |
0.26 |
0.27 |
0.26–0.35 |
0.32 |
|
Basal diameter of scutellar
spine |
0.13 |
0.13 |
0.11 |
0.13 |
0.11 |
0.19 |
0.11–0.19 |
0.16 |
|
Fore coxa
length |
0.84 |
0.85 |
0.68 |
0.83 |
0.78 |
broken |
0.78–0.86 |
0.86 |
|
Fore femora length |
1.70 |
1.81 |
1.43 |
1.66 |
1.58 |
broken |
1.43–1.81 |
1.79 |
|
Fore femora maximum width |
0.37 |
0.41 |
0.30 |
0.35 |
0.33 |
broken |
0.33–0.37 |
0.36 |
|
Longest hair: Fore femora |
0.31 |
0.32 |
0.27 |
0.29 |
0.25 |
broken |
0.25–0.29 |
0.29 |
|
First tarsal segment length |
0.66 |
0.68 |
0.66 |
0.72 |
0.74 |
0.68 |
0.66–0.74 |
0.68 |
|
Last tarsal segment length |
0.10 |
0.10 |
0.10 |
0.10 |
0.12 |
0.10 |
0.10–0.12 |
0.10 |
|
Wing length |
4.09 |
4.30 |
3.84 |
4.14 |
3.84 |
3.16 |
3.16–4.56 |
4.56 |
*All measurements in mm. **Specimens are provided with respective
accession/ reference numbers in parenthesis.
Table 2. Ratio of bivariate characters
of C. whitei*
|
Ratio of Characters |
Male1 (4004) |
Male 2 (4005) |
Male 3 (4006) |
Male 4 (4007) |
Male 5 (4008) |
Male 6 (4009) |
Range (min.-max.) |
Female (4010) |
|
Eye span/ body length |
1.24 |
1.32 |
0.97 |
1.18 |
1.07 |
0.87 |
0.87–1.32 |
0.90 |
|
Inner vertical bristle/Eye stalk middle
width |
4.46 |
4.71 |
5.90 |
4.31 |
4.58 |
5.75 |
4.31–5.90 |
5.09 |
|
Outer vertical bristle/Eye stalk middle
width |
2.79 |
2.54 |
3.38 |
2.80 |
2.10 |
2.69 |
2.54–3.28 |
3.08 |
|
Arista length/Inner vertical bristle |
1.41 |
1.06 |
1.52 |
1.30 |
broken |
1.36 |
1.30–1.52 |
1.30 |
|
Arista length/Outer vertical bristle |
2.20 |
1.89 |
2.57 |
2.21 |
broken |
2.28 |
1.89–2.57 |
2.14 |
|
Scutellum: length/ width |
0.41 |
0.37 |
0.37 |
0.47 |
0.49 |
0.41 |
0.37–0.52 |
0.52 |
|
Scutellar spine length/ Scutellum
length |
4.45 |
4.73 |
4.54 |
3.93 |
4.25 |
3.89 |
3.75–4.73 |
3.75 |
|
Longest hair at base of eye stalk/
longest hair at base of antennae |
2.0 |
2.0 |
1.50 |
2.33 |
2.0 |
1.50 |
1.50–2.67 |
2.67 |
|
First tarsal segment/last tarsal segment |
6.60 |
6.80 |
6.60 |
7.20 |
6.16 |
6.80 |
6.16–7.20 |
6.80 |
*Specimens are provided with respective accession numbers in
parentheses.
DISCUSSION AND CONCLUSIONS
Feijen
(2011) considered Cyrtodiopsis to be a weakly
defined genus from the oriental region due to inclusion of several unrelated
species at different times but preferred its distinct identity sensu Shillito (1940) in
view of distinctive morphological attributes (chiefly in having prominent incrassate
constrictions on apex of fore femora and low tubercles on the inner bases of
fore tibiae) absent in the species of other genera under the family. Earlier, cladistic
study using mitochondrial genes made by Baker et al. (2001), Meier & Baker
(2002) and Földvári et al. (2007) revealed phylogenic relationship between Teleopsis
and Cyrtodiopsis but molecular distinctions
between the two genera based on four marker genes, particularly between T. thaii and T. breviscopium,
were not conclusive (Földvári et al. 2007). To date, the presence of sharp incrassate
apical constriction in fore femora and corresponding rounded tubercles on the
basal parts of the fore tibia are the most robust and unique characters to the
species of Cyrtodiopsis. Also, supra-alar spines, characteristic of
all Teleopsis species, are absent in Cyrtodiopsis species. The presence of several hairs with bifid or
split tips on the body of C. whitei could
possibly be another unique character of this genus till further study reveals
its presence in other species of Cyrtodiopsis
and possibly in other genera of Diopsidae.
Despite prominent differences in morphometry between the two populations of whitei from geographically isolated locations
of India and Malaysia, as evident from the taxonomic key above, we do not
describe these specimens as a new species, because both populations share
fundamental similarities in characters of fore wings, pollinosity
distribution in thorax, body coloration, and general structure of
genitalia. The observed differences in morphometry and presence of some of the body hairs with
bifid tips in whitei from northeast India,
among others, might represent the influence of differences in environments of
the two habitats separated by several hundred miles. This study has founded the basis of future
study to ascertain the prevalence of these characters when more specimens
become available from these or nearby areas and also from the original type
locality.
Key to the identification of species of Cyrtodiopsis
IVB on high tubercles, the tubercles about 0.75 times the middle width
of eye stalks; infra-alar spines roundish; forewings with sub-apical band
darker and wider than the apical bands, with a nearly circular pale spot in the
radial-medial cell (R4+5), completely isolated from other cells
..................................................................................................................................
currani
IVB on low tubercles, the
tubercles at most 0.40 times the middle width of eye stalks; infra-alar spines dorso-ventrally flattened with rounded tips; forewings with
sub-apical bands pale to pale brown, with or without a spot in the
radial-medial cell (R4+5), not
completely
separated from other spots or cells
...................................................................................................................................
2
Thorax shining yellow, not pollinose;
forewings with sub-apical bands narrow to wide, completely separated from the
middle band ...............................................................................................................................................................................................
dalmanni
Thorax shining glossy yellow
or brown, distinctly pollinose in mid-dorsum;
forewings with or without a median pale spot between sub-apical and middle
bands
……………………………………………........................................................................................…………..…………
3
Eye span, on average, 11.18mm long, 1.39 times the body length; scutellar spines up to 5.0 times the scutellar
length ……………… thaii
Eye span, on average, less
than 8.0mm long, up to 1.25 times the body length; scutellar
spines 3.50–4.0 times but never more than 4.30 times the scutellar
length; pronotum and mesonotum
pollinose, shining brown pleurally
….......……………………… whitei complex
OVB up to1.35 times and IVB up to 4.50 times as long as the width of eye
stalks in the middle; eye span about 7.93mm long and 1.25 times the body
length; cerci of male genitalia with several long, dispersed setae along their
surface; habitat: laboratory culture specimens sourced from primary tropical
rainforest in Malaysia (based on description from Földvári et al. 2007)
.............................................................................................................................................................................................
whitei from Malaysia
OVB 2.10–3.78 times and IVB 4.31–5.91 times as long as the width of eye
stalks in the middle; eye span 3.99–5.93 mm long (Table 1) and up to 1.08 times the body length
(Table 2); cerci of male genitalia on each side bears 5 hairs, 2 smaller ones
protected outwards and 3 longer ones projected inwards (based on actual
specimens); habitat: tropical moist deciduous forest ..............................................................................................................................................................................
whitei from northeastern
India
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