close
Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Dec 18:1005:21-55.
doi: 10.3897/zookeys.1005.57629. eCollection 2020.

† Camelosphecia gen. nov., lost ant-wasp intermediates from the mid-Cretaceous (Hymenoptera, Formicoidea)

Brendon E Boudinot  1   2 , Vincent Perrichot  3 , Júlio C M Chaul  4
Affiliations

† Camelosphecia gen. nov., lost ant-wasp intermediates from the mid-Cretaceous (Hymenoptera, Formicoidea)

Brendon E Boudinot et al. Zookeys. .

Abstract

Fossils provide primary material evidence for the pattern and timing of evolution. The newly discovered "beast ants" from mid-Cretaceous Burmite, †Camelosphecia gen. nov., display an exceptional combination of plesiomorphies, including absence of the metapleural gland, and a series of unique apomorphies. Females and males, represented by †C. fossor sp. nov. and †C. venator sp. nov., differ in a number of features which suggest distinct sexual biologies. Combined-evidence phylogenetic analysis recovers †Camelosphecia and †Camelomecia as a clade which forms the extinct sister group of the Formicidae. Notably, these genera are only known from alate males and females; workers, if present, have yet to be recovered. Based on ongoing study of the total Aculeata informed by the beast ant genera, we provide a brief diagnosis of the Formicoidea. We also provide the first comprehensive key to the major groupings of Mesozoic Formicoidea, alongside a synoptic classification in which †Zigrasimeciinaestat. nov. and †Myanmyrma maraudera comb. nov. are recognized. Finally, a brief diagnosis of the Formicoidea is outlined.

Keywords: Mesozoic revision; classification; identification key; morphology; paleontology; phylogeny; taxonomic synopsis.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Mandibles of representative FormicoideaA †Camelosphecia fossor gen. et sp. nov. holotype female, lateral oblique (ANTWEB1038930) B †Gerontoformica species, male, dorsal or full-face view (ANTWEB1032638) C †Chonidris insolita holotype female, anterolateral oblique (FANTWEB00022, AntWeb: Vincent Perrichot).
Figure 2.
Figure 2.
Mouthparts of †Camelomecia clade genera A †Camelosphecia fossor gen. et sp. nov. holotype female, dorsolateral oblique (ANTWEB1038930) B †Camelomecia janovitzi holotype female, anterolateral oblique (AMNH-BUTJ003, AntWeb: Phil Barden).
Figure 3.
Figure 3.
Cranium and mandibles of stem FormicidaeA †Linguamyrmex brevicornis, worker, lateral view (FANTWEB00035, AntWeb: Vincent Perrichot) B †Gerontoformica species, worker, dorsolateral oblique (ANTWEB1032639).
Figure 4.
Figure 4.
Cranial armaments of †HaidomyrmecinaeA †Chonidris insolita female, dorsolateral oblique (FANTWEB00033, AntWeb: Vincent Perrichot) B †Aquilomyrmex huangi female, ventrolateral oblique (FANTWEB00023, AntWeb: Vincent Perrichot) C †Linguamyrmex rhinocerus, female, lateral (FANTWEB00016, AntWeb: Vincent Perrichot).
Figure 5.
Figure 5.
Facial seta and chaeta arrays of trigger-hair-bearing †HaidomyrmecinaeA †Haidomyrmex cerberus, holotype worker, dorsolateral oblique (BMNHP20182, AntWeb: Vincent Perrichot) B †Ceratomyrmex ellenbergeri, worker, dorsal anterolateral oblique (FANTWEB00005, AntWeb: Vincent Perrichot).
Figure 6.
Figure 6.
Cranial conformation of clypeal-brush-bearing †HaidomyrmecinaeA †Haidomyrmex cerberus worker, lateral (FANTWEB00017, AntWeb: Vincent Perrichot) B †Dilobops bidentata worker holotype, dorsolateral oblique (FANTWEB00039, AntWeb: Gabriel Melo).
Figure 7.
Figure 7.
Clypeus and cranium of Antennoclypeata and †Sphecomyrmines A †Brownimecia clavata holotype worker, full-face (from Grimaldi and Engel 2005, used with permission of the publisher) B †Gerontoformica species, worker, dorsal (ANTWEB1032629).
Figure 8.
Figure 8.
Cranial and mesosomal profiles of Antennoclypeata A †Brownimecia clavata holotype worker, lateral (AMNH-NJ667, AntWeb: Dave Grimaldi and Vincent Perrichot) BAustroponera castanea (Mayr, 1865) worker, lateral (CASENT0249168, AntWeb: Ryan Perry).
Figure 9.
Figure 9.
Facial views of †Zigrasimeciinae stat. nov. and †Sphecomyrminaesensu strictoA †Zigrasimecia species, worker, posterodorsal oblique (ANTWEB1032623) B †Zigrasimecia species, worker, anterodorsal oblique (ANTWEB1032660) C †Gerontoformica species, worker, dorsal (ANTWEB1032649).
Figure 10.
Figure 10.
Cranial gestalts of †Sphecomyrminaesensu strictoA †Myanmyrma maraudera (Barden & Grimaldi, 2016) comb. nov., holotype worker, full-face (JZCBU1846, AntWeb: Phillip Barden) B †Gerontoformica species, worker, full-face (ANTWEB1038348).
Figure 11.
Figure 11.
Facial views of †Sphecomyrminae which have short mandibles A †Sphecomyrma mesaki Engel & Grimaldi, 2005, holotype worker, anterodorsal oblique (AMNH-NJ1023, AntWeb: Dave Grimaldi and Vincent Perrichot) B †Gerontoformica species, worker, full-face (ANTWEB1032418).
Figure 12.
Figure 12.
Body profiles of †Gerontoformica pilosa and orientalis species groups A †Gerontoformica pilosa Barden & Grimaldi, 2014, worker profile (ANTWEB1038931) B †Gerontoformica species, worker profile (ANTWEB1032649).
Figure 13.
Figure 13.
Holotype of †Camelosphecia fossor sp. nov. A lateral view of right side of head B full face view of head, right margin blurred on this view due to a folding of the facet. Box on bottom right evidencing scape under fluorescent microscopy C detail of clypeus, mandibles and labrum under fluorescent microscopy D posterodorsal view of anterior section of funiculus (pedicel plus flagellum), evincing pedicel and antennomeres III and IV. Abbreviations: a3–5, antennomeres III–V; abdsw, abductor swelling; bs, bubble stream; ce, compound eye; cl, clypeus; clb, clypeal lobe; clt, clypeal teeth; crcond, cranial condyle; md, mandible; mm, masticatory margins; lbs, labral chaetae; mdcond, mandible condyle; mxp, maxillary palps; oc, ocelli; occ, occipital carina; pd, pedicel; prvmdpr, posteroventral mandible process; sc, scape. Scale bars: 0.2 mm (A, B); 0.1 mm (C); 0.02 mm (D).
Figure 14.
Figure 14.
Holotype of †Camelosphecia fossor sp. nov. A profile of left side of body B profile of right side of body C dorsal view of mesosoma D delimited area of C under fluorescent light E details of the legs, especially the forelegs. Abbreviations: A2–A3; abdominal segments 2 and 3; aprntr, anterior pronotal rim; ca, calcar; mscx, mesocoxa; msfm, mesofemur; msnt, mesonotum; mspl, mesopleural region of mesopectus; mssctm, mesoscutum; mssctl, mesoscutellum; mtcx, metacoxa; mtfm, metafemur; mtpl, metapleural region of metapectus; plant, plantulae; pr, prora; prcx, procoxa; pretc, pretarsal claws; prfm, profemur; prnt, pronotum; prop, propodeum; proppj, propodeal projection; prots, protarsomeres I and II chaetae; prtbss, distal protibia stout chaeta; psctc, parascutal carina; sp, propodeal spiracle; strg, strigil. Scale bars: 0.2 mm.
Figure 15.
Figure 15.
A–C †Camelosphecia spp. females examined by images. Specimens in A (BALBuTJ_36) and C (BALBuTJ_40) are likely conspecifics to †C. fossor. Specimen in B (BALBuTJ_38) is probably another species in the genus, not described in here (images by Phil Barden, used with permission) D, E are generalized schemes of †Camelosphecia habitus and forewing, respectively, as interpreted from all specimens examined. Metathoracic sclerites in A–C are indicated with green dots. In D, pedicel and flagellomeres are omitted for simplification. Abbreviations as in Figure 14, except for prstA4, presternite of A4; prpl, propleuron; tbsp, tibial spurs; stA4, sternite of A4; stng, sting. Wing venation abbreviations: C, costal vein; Sc, subcostal vein; R, radial vein; Rs, radial sector vein; M, medial vein; Cu, cubital vein, A, anal vein; +, indicates composite vein; f#, indicates free abscissa index; 2r-rs, second radiosectoral crossvein; 2rs-m, second sectoriomedial crossvein; 1m-cu, first mediocubital crossvein; 1cu-a, first cubitoanal crossvein; R (bc), radial or “basal” cell; 1+2R (smc1), undifferentiated first and second distal radial cells or “first submarginal cell”; 3R (mc1), third distal radial or “first marginal” cell; 1Rs (smc2), first sectorial or “second submarginal” cell; 1M (dc1), first medial or “discal” cell; 1Cu (sbc), first cubital or “subbasal” cell; 2Cu (sdc1), second cubital or “first subdiscal” cell.
Figure 16.
Figure 16.
†Camelosphecia venator sp. nov. holotype (NIGP163574) A, D right and left profile view of body, respectively B, C right and left profile view of head, respectively E left mesosoma zooming. Abbreviations: ce, compound eye; cl, clypeus; md, mandible; mm, masticatory margins; oc, ocelli; occ, occipital carina; A2–A3; abdominal segments 2 and 3; mscx, mesocoxa; mspl, mesopleural area of mesopectus; mssctm, mesoscutum; mtcx, metacoxa; mtpl, metapleural area of mesopectus; oms, oblique mesopleural sulcus; pr, prora; prcx, procoxa; prnt, pronotum; prop, propodeum. Note that indication of clypeus in C is exactly at its margin as seen in profile, which is concave, and should not be confused with convex right compound eye margin, also indicated. Clypeal concave shape is better evidenced in figure B. Also in C, mm indicated is from the right mandible, while mandible indicated is that of the left side. Scale bars:1 mm (A, D); 0.2 mm (B, C, E).
See this image and copyright information in PMC

References

    1. Barden P. (2017) Fossil ants (Hymenoptera: Formicidae): ancient diversity and the rise of modern lineages. Myrmecological News 24: 1–30. 10.25849/myrmecol.news_024:001 - DOI
    1. Barden P, Engel MS. (2019) Fossil social insects. Springer Nature, Switzerland, 21 pp 10.1007/978-3-319-90306-4_45-1 - DOI
    1. Barden P, Grimaldi DA. (2012) Rediscovery of the bizarre Cretaceous ant Haidomyrmex Dlussky (Hymenoptera: Formicidae), with two new species. American Museum Novitates 3755: 1–16. 10.1206/3755.2 - DOI
    1. Barden P, Grimaldi DA. (2013) A new genus of highly specialized ants in Cretaceous Burmese amber (Hymenoptera: Formicidae). Zootaxa 3681: 405–412. 10.11646/zootaxa.3681.4.5 - DOI - PubMed
    1. Barden P, Grimaldi DA. (2014) A diverse ant fauna from the mid-Cretaceous of Myanmar (Hymenoptera: Formicidae). PLoS ONE 9(4): e93627. 10.1371/journal.pone.0093627 - DOI - PMC - PubMed

LinkOut - more resources