Corresponding author: David A. Grimaldi (
Academic editor: M. Engel
Thirteen species of basal Brachycera (11 described as new) are reported, belonging to nine families and three infraorders. They are preserved in amber from the Early Cretaceous (Neocomian) of Lebanon, Albian of northern Spain, upper Albian to lower Cenomanian of northern Myanmar, and Late Cretaceous of New Jersey USA (Turonian) and Alberta, Canada (Campanian). Taxa are as follows, with significance as noted: In
This is the fourth paper in a series devoted to the Cretaceous record of brachyceran flies preserved in amber, the original work being a treatment of orthorrhaphans and Cyclorrhapha (
Specimens were prepared according to the protocols described in
American Museum of Natural History, Entomology Section, New York.
Azar Collection, presently housed in Musée national d’Histoire naturelle, Paris.
University of Kansas Division of Entomology, Natural History Museum, Lawrence.
Museo de Ciencias Naturales, Álava, Spain.
Natural History Museum, London.
Royal Tyrrell Museum of Palaeontology, Drumheller, Alberta, Canada.
It is a pleasure for the senior author to dedicate this paper to Kumar Krishna, world authority on the
This lineage comprises three living families, the
We were able to study two additional specimens of this very primitive genus of stratiomyid, both in Canadian amber collected by Ted Pike from Grassy Lake, Alberta (Campanian) (
RTMP 96.9.1117: Amber is a typical clear, dark yellow with reddish flow lines; it also contains a small spider. The piece is a cylindrical runnel 12 × 4 × 2 mm, with the fly preserved near the middle, which was embedded in epoxy at the AMNH and trimmed to 9 × 13 × 4 mm (including epoxy) for better observation. The fly is laterally very flattened, especially the thorax, and is a male (though details of the genitalia are not observable). Unfortunately, the apex of the mid tibia cannot be observed in detail, so the apparent absence of tibial spurs is uncertain. Wing is slightly distended in length, but otherwise the venation is very similar to
RTMP 96.9.1230: Fly is also preserved in a cylindrical runnel of amber, 7 × 3 (diam.) mm, and embedded in epoxy for careful trimming. The fly is lying at the rounded end of the runnel, with its dorsal surface against the surface of the flow. The thorax is partly decayed and wing venation is obscured. The antenna and mouthparts are visible in ventral view. Specimen is a male, but its genitalic details are also not observable. Mid tibia appears to have a small apical spur, contrary to the original description of the species but in agreement with
Antennal flagellum submoniliform, with approximately 7 short flagellomeres tapered in width apicad; articulation between basal 3 flagellomeres faint. Protibia lacking spurs; mesotibia with two short apical spurs (c. 50 µm length). Metatibia probably with one pair of short apical spurs. Vein Rs branches from R1 in the distal third of vein R. Stem of R4+5 straight, R4 curved basally, long and subparallel to R5. Cell d long and narrow, length approximately 3.5x the width; cell m3 absent.
From the Greek, Λυσιστράτη, meaning “army disbander”, after the comedy by Aristophanes and in reference to the common name for
The Recent and primitive genus
The oldest fossil stratiomyiid is
As for the genus.
Body length 5.75 mm. Head length 0.60 mm. Specimen well preserved, but only visible in lateral view. Head slight distorted, with right antenna slightly separated from base. Eyes bare, large, covering most of head; facets not differentiated. Ocellar triangle not visible. Antenna submoniliform, with approximately 7 short flagellomeres tapered in width distad (articulations between 3 basal flagellomeres faint, number of articles difficult to discern); length of antenna approximately equal to length of head; length of flagellum 3× that of scape + pedicel combined. Distal flagellomere distinctly longer and narrower than more basal ones. Palpi reduced, segmentation not discernable; labellum well developed. Thorax: Mesonotum short and compact, finely pilose dorsally, without macrosetae. Scutellum without spines. Surface of notum slightly metallic and foveolate. All legs preserved; protibia lacking spurs; mesotibia with two apical spurs (50 µm long); probably one short apical spur on metatibiae. Length of hind basitarsomere equal to that of tarsomeres 2–5. Wing length 3.05 mm, width 0.75 mm; hyaline, vein Sc straight, length approximately 0.45× wing length, complete. Lengths of costal section of wing between apices of R2+3 and R1 equal to that between R1 and Sc. R2+3 arising distant from r-m. R4+5 straight, R4 curved at base, long and subparallel to R5. Veins M1 and M2 separated at discal cell. Cell m3 absent, vein M3 either absent or fused to CuA1. Abdomen elongate; basal 4 or 5 segments large and wide; apical 5 segments narrow and telescoping. Cercus composed of 2 segments, basal segment longer than apical one.
Holotype, female, MCNA 12698, SPAIN: Alava, Peñacerrada I (Moraza), Escucha Formation, Lower Cretaceous (Albian). Deposited in MCNA. Specimen is well preserved in a clear piece of amber 10 × 7 × 1.5 mm, partially missing the left side of the thorax and the left wing; the amber is embedded in epoxy 15 × 13 × 2 mm. An empidoid fly (
From the Latin noun,
Antenna thick, greatest width (in middle) 0.25x total length, with apparently 7 flagellomeres; protibia without apical spur; most distinctive features are in venation, which distinguishes this genus from other Mesozoic xylomyids by: vein M (separating cells br and bm) weak; cell m3 very small, width and length approximately half that of cell d (these are of equivalent size in other xylomyids, or m3 is slightly smaller), and, very distinctively, vein R2+3 is uniquely lost.
From
The closed wing cell m3 is a feature also seen in some
The oldest fossil record of
As for genus.
Holotype, sex unknown, Lebanon (Early Cretaceous, Neocomian): “Hammana/Mdeiru, Aptien inférieur,” in Azar Collection no. 391, temporarily deposited in Musee National d’histoire Naturelle, Paris
Patronym, for Dany Azar, for his extensive contributions to the paleontology of Lebanese amber.
?
MCNA 8833, Spain: Álava: Peñacerrada I, Escucha Formation, Lower Cretaceous (Albian). Specimen lacks a head, and the thorax and abdomen are only partially preserved.
Because of the incomplete preservation, a precise diagnosis and family placement of the specimen is not possible, so we did not provide a name and formal description. There are genera of lower Brachycera in several families that have a venation similar to this fossil, including the closed cell m3. A distinctive feature of the fossil is vein R5 ending at the apex of the wing. This is rarely seen in the lower Brachycera, occuring, for example, in
Venation differs from congener by
AMNH NJ-1862 (holotype): Body length 1.0 cm, wing length 8.0 mm. Most of left lateral view and some of dorsal, right lateral, and frontal view of face observable. Specimen apparently female.
Holotype (sex unknown), AMNH NJ-1862, New Jersey (USA): Middlesex Co., Sayreville, White Oaks [Old Crossman’s] pits (Turonian), collected by Stephen Swolensky. Observation of the fly was optimized by embedding the amber in epoxy under vacuum and trimming very close to surfaces of the fly, but the specimen is not well preserved, being occluded with a reddish, crazed layer over most of the body and by similar internal fractures in the piece, as well as by a suspension of fine particles in the amber. Piece is irregular in shape, 10 × 13 mm in largest dimensions. Study of the specimen might benefit from microtomography.
Paratype (sex unknown), AMNH NJ-1081, in Late Cretaceous (Turonian) amber from Crossman’s Pits, Sayreville, New Jersey. Fly is partially preserved: besides the entire right wing and a very small portion of left wing, only the dorsal surfaces of the abdomen and thorax remain; the head and legs are entirely lost. The amber piece is triangular and approximately 19 × 8 × 5 mm, embedded in epoxy but trimmed and polished so as to expose a dorsal view of the fly. The amber itself is light yellow and turbid, with a thick suspension of organic particles that obscures much of the fly. AMNH NJ-1081 differs from NJ-1862 by the following minor venational details: R1 slightly longer, Rs branches from R1 at a more acute angle, proximal end of cell d slightly more shallow V-shaped; A2 slightly shorter. Both specimens are also very similar in body shape and size.
“from New Jersey,” in reference to provenance.
These are the only tabanids known to be preserved in Cretaceous amber. Other tabanids in amber are from the Miocene of the Dominican Republic and the Eocene Baltic amber (
“
“
A minute, distinctive acrocerid with medial margins of male eyes contiguous above and below antennae, hind and ventral margins of eye strongly emarginate; antennae minute, in middle of head; proboscis vestigial; eyes bare, thorax with very sparse, fine setulae; postpronotal lobes of moderate size, slightly protruding; abdomen devoid of microtrichia and glabrous (possibly reflective). Mediolobus (i.e., “pulvilliform empodium”) and pulvilli pad-like. Venation distinct: All veins sclerotized, none faint; C ends at apex of R4+5; Sc short; R1 and Rs fork at ca. 0.4× length of wing; cells br and bm continuous, not bissected (vein M extremely faint or lost from this area); two closed radial cells (r4+5 and d), plus cell m3 present; R4+5 ends near apex of wing, without an apical fork of R4-R5 encompassing apex of wing.
Patronym in honor of Evert Schlinger, Emeritus Professor of entomology at the University of California, Berkeley, who has devoted his career to the study of
This is a very distinctive, minute acrocerid – in body size quite the opposite of its generic namesake – which is unique for the venation, genitalia, and virtually bare body. Most acrocerids have long, fine pile on the thorax and abdomen, and many have it on the eyes and calypters. Vein Sc is very short in the fossil, and cells br and bm are contiguous. In addition, apparent retention of freely articulated gonostyli in the male genitalia appears to be a significant feature of the genus, since loss of articulated gonostyli through fusion with the gonocoxites is considered an apomorphy of the remainder of the family (
As for the genus.
Body length 3.0 mm, wing length 2.1 mm.
Holotype, Male, AMNH Bu332a, in Burmese amber. Paratype, AMNH Bu332b, in same piece of amber. Both specimens are entirely preserved, though slightly obscured by debris and a few small fractures. The specimens occur in a runnel-shaped piece of dark but transparent amber, 16 × 7 mm, which has been embedded in epoxy. The piece also contains 1
Latin, adjective, in reference to the very small size of the species.
A small, primitive acrocerid in Burmese amber easily separated from
Combination derived from Burma (the pre-junta name for Myanmar) and
Derived acrocerid features that
As for genus.
Wing length approximately 1.4 mm, body length approximately 2.0 mm.
Holotype, Male, AMNH Bu-RS1, in Burmese amber. The holotype is in excellent condition, though only the ventral and lateral portions are visible (the dorsal surface is obscured by the depth and curvature of the amber). The amber is clear yellow and the fly lies on an internal surface plane that contains bubbles and stellate trichomes. The original piece was drop-shaped, 10 × 16 mm, and contained a small spider, cecidomyiid midge, and berothid lacewing. These inclusions were separated from the fly.
Patronym, for Dr. R.D.A. (Ru) Smith, who generously donated the specimen to the AMNH from his personal collection.
R1 long, apex reaching to 2/3 length of wing; R1 branching off of the stem of R quite distad, R2+3 long, branching off of Rs in the distal half of the wing; cells br and bm large, length nearly half that of wing; M1+2 forked; vein A1 either incomplete or absent. Mesoscutum strongly arched; it and abdominal tergites devoid of bristle-like setae or long pilosity; apical tibial spurs lacking. Body size minute, ca. 1.0 mm in length.
Derived from
The family placement of the two new species in this genus is not entirely certain, particularly since in mythicomyiids vein R2+3 is typically short and its apex fused with R1. The genus is placed in the
Lastly, it is interesting to note that the fossil record of
Distinguished from
A minute fly, body length c. 1.1 mm, thorax length 0.5 mm, wing length 1.15 mm.
Holotype, male: Myanmar: Kachin (northern Myanmar), in Burmese amber, KU Bu079 (Univ. Kansas, Division of Entomology, Natural History Museum). The amber piece containing the holotype is a very transparent, deep amber color, 14 × 7 × 5 mm, which also contains 2 scelionid wasps. The minute holotype is at the surface of a fractured corner.
in reference to the presence of an anal vein (i.e., the Latin noun
cf.
A minute fly, wing length 0.85 mm.
Holotype, Male: Myanmar: Kachin (northern Myanmar), latest Albian to earliest Cenomanian. AMNH Bu1552. Specimen is displayed with wings and legs outspread, but body is only moderately well preserved, with some details obscured beneath layer of deep reddishness. Dorsal view is better than ventral view.
It could be argued that these two species might warrant separate genera, based on the differences of antennae, wing fringe, epandrial setae, and proportions of the wing. However, other than the presence/absence of the anal vein, the wing venation is very similar between the two species.
This asiloid group includes the Recent families
Body stout, abdomen short (length about equal to that of thorax); eyes large, bare; antenna with 3 flagellomeres, second article and third (style) minute; palp one-segmented; legs and thorax with bristle-like setae, no pilosity except for postoccipital region; hind coxa with small knob on anterior surface; thickness of metatarsi equal that of metatibial base; wing with C ending between apices of R5 and M1, apex of R5 ending slightly subapically; R4 and R5 divergent, not parallel for any part of their lengths, base of R4 not perpendicular to stem of R4+5 and R5 .
Patronym in honor of a great colleague and friend to the senior author, Prof. Kumar Krishna. Appropriately,
As for the genus.
Small fly, total body length ca. 2.70 mm, thorax length 1.0 mm, wing length (estimated) 2.50 mm.
Holotype, female, AMNH Bu131: Myanmar: Kachin State, near Mytikyina (mid-Cretaceous: Late Albian – Cenomanian). Specimen is complete, but the right wing (the only one observable) is folded, and most of the dorsal view is obscured, compromising a complete reconstruction of the venation (
In reference to the country of origin.
There is little question this fossil belongs to the therevid group, albeit unusually small (within the range in body size of some apsilocephalids and a few genera of
Fossil
Fossil
Undescribed sp.: Early Cretaceous amber, Wealden, UK (
The position of
This family contains the sole Recent species
Distinguished from the 4 other species in the genus (known only in New Jersey amber) by venation: vein C ending just slightly beyond apex of R4 (not at apex of R5); Sc long, distally incomplete (more so than in
Based on a virtually complete, well-preserved female. Body length (excluding antennae) 1.40 mm; thorax length 0.50 mm; wing length 0.95 mm.
Holotype female, AMNH Bu-098, in amber from Myanmar: Kachin, Tanai Village (on Ledo Rd. ca. 105 km Myitkyna). Amber is a deep, clear yellow, 15 × 10 × 5 mm, and was embedded in epoxy and trimmed to a wedge shape in order to maximize a full lateral view of the fly and its venation. The piece also contains a male chironomid and a thrips (
From Burma (Myanmar).
This is a highly specialized family of
(emended). Distinguished from
Distinguished from the other two species of the genus, which are known only from males (
Body length (tip of basal flagellomere to posterior-most surface of tergite VIII) 2.15 mm. HEAD: Hemispherical in female; eyes very large, covering most of head, only small strip of gena exposed [view of face and frons not visible]. Dorsal eyes facets approximately 0.5× diameter of ventral facet; eye completely bare, no interfacetal setulae. No setae apparent on gena or frons. Ocelli possibly on small tubercles – small, digitate lobes in this area [but details obscure]. Antenna with large, crescent-shaped basal flagellomere; pedicel apparently small [indistinct]. Proboscis and palps not visible [ventral surface of head covered with bubble]. Posterior surface of head evenly and shallowly concave. Cervical region long; head not adpressed to pronotum.
Holotype, Female: Myanmar, Kachin State, Early Cenomanian. Specimen is in excellent condition and is in the private collection of James Zigras.
Patronym for James Zigras, for allowing preparation and study of this remarkable specimen.
With little question the oviscapt of
Distinctive small flies (body length less than 1.5 mm) with antennal stylus arista-like and terminal, having a single article; face without ptilinal suture; median margins of eyes very close on frons; maxillary palpus two-segmented; mesonotum with dorsocentral and scutellar setae; wing venation highly reduced, with R2+3 and R4+5 each unbranched, M unbranched and evanescent at both ends, Cu simple; female with pair of long, digitate, unsegmented cerci.
From Myanmar, country of origin, and –
This is a perplexing little fly. Chaetotaxy of the thorax, the wing venation, and even body shape are strikingly similar to acalyptrate flies in the
As for genus.
Body size small, length 1.35 mm (excluding antennae and cerci), slender. Wing length 1.05 mm.
Holotype, female, AMNH Bu1616, in amber from northern Myanmar: Kachin State, Tanai Village, 105 km NW Mytikyina. The holotype is the sole inclusion in a clear amber-colored piece 9 × 6 × 2 mm. Ventral surface of the thorax and the abdomen are compressed, and a crack through the thorax obscures some details. The left wing of the unique specimen is well preserved, but venation is optimally observed by tilting and observing the piece at various oblique angles. Right wing is twisted, but in oblique view additional details of venation are visible.
L., for like, and
We are grateful to the institutions and individuals who loaned specimens for this study and patiently awaited the long gestation of this paper, including Dany Azar, Michael Engel, Ru Smith, and James Zigras. The donation of the holotype of