Geometer moth

{{short description|Family of insects}}{{redirect|Inchworm}}

{{redirect|Geometridae|the mollusc family|Geomitridae}}

{{Automatic taxobox

| fossil_range = Priabonian to Recent {{fossilrange|35|0}}

| image = Chiasma species W IMG 2775.jpg

| image_caption = Chiasmia species from Ennominae

| taxon = Geometridae

| authority = Leach, 1815

| subdivision_ranks = Subfamilies

| subdivision =

}}

The geometer moths are moths belonging to the family Geometridae of the insect order Lepidoptera, the moths and butterflies. Their scientific name derives from the Ancient Greek {{lang|grc-Latn|geo}} {{lang|grc|γεω}} (derivative form of {{lang|grc|γῆ}} or {{lang|grc|γαῖα}} "the earth"), and {{lang|grc-Latn|metron}} {{lang|grc|μέτρον}} "measure" in reference to the way their larvae, or inchworms, appear to measure the earth as they move along in a looping fashion.{{cite web |last1=Robin McLeod |first1=John |last2=Balaban |first2=Jane |last3=Moisset |first3=Beatriz |last4=Entz |first4=Chuck |date=April 27, 2009 |title=Family Geometridae - Geometrid Moths |website=BugGuide |url=http://bugguide.net/node/view/188 |access-date=April 2, 2011}} Geometridae is a very large family, containing around 23,000 described species;{{cite web |title=Lepidoptera Barcode of Life |url=http://www.lepbarcoding.org/geometridae/species_checklists.php |access-date=2017-07-11 |archive-date=2017-07-12 |archive-url=https://web.archive.org/web/20170712051748/http://www.lepbarcoding.org/geometridae/species_checklists.php |url-status=usurped }}{{citation |author=Scoble, M. J. |title=Geometrid Moths of the World: A Catalogue (Lepidoptera, Geometridae) |volume=1 and 2 |publisher=CSIRO Publishing and Apollo Books |location=Stenstrup |page=1016 |year=1999 |language=de}} over 1400 species from six subfamilies are indigenous to North America alone. A well-known member is the peppered moth, Biston betularia, which has been the subject of numerous studies in population genetics. Several other geometer moths are notorious pests.

Caterpillars

The name "Geometridae" ultimately derives from Latin {{lang|la|geometra}} from Greek {{Lang|el|γεωμέτρης}} ("geometer", "earth-measurer"). This refers to the means of locomotion of the larvae or caterpillars, which lack the full complement of prolegs seen in other caterpillars, with only two or three pairs at the posterior end instead of the usual five pairs. Equipped with appendages at both ends of the body, a caterpillar clasps with its front legs and draws up the hind end, then clasps with the hind end (prolegs) and reaches out for a new front attachment, creating the impression that it measures its journey. The caterpillars are accordingly called "loopers", "spanworms", or "inchworms" after their characteristic looping gait. The cabbage looper and soybean looper are not inchworms but caterpillars of a different family. In many species of geometer moths, the inchworms are about {{convert|25|mm|1|abbr=on}} long. They tend to be green, grey, or brownish and hide from predators by fading into the background or resembling twigs. When disturbed, many inchworms stand erect and motionless on their prolegs, further increasing this resemblance. Some have humps or filaments, or cover themselves in plant material. They are gregarious and are generally smooth. Some eat lichen, flowers, or pollen, while some, such as the Hawaiian species of the genus Eupithecia, are carnivorous. Certain destructive inchworm species are referred to as "cankerworms".{{cite journal |last1=Frank |first1=Steven D. |title=Bad neighbors: urban habitats increase cankerworm damage to non-host understory plants |journal=Urban Ecosystems |date=1 December 2014 |volume=17 |issue=4 |pages=1135–1145 |doi=10.1007/s11252-014-0368-x |bibcode=2014UrbEc..17.1135F |url=https://link.springer.com/article/10.1007/s11252-014-0368-x |language=en |issn=1573-1642|url-access=subscription }}

In 2019, the first geometrid caterpillar in Baltic amber was discovered by German scientists. Described under Eogeometer vadens, it measured about {{convert|5|mm|in|abbr=on}} and was estimated to be 44 million years old, dating back to the Eocene epoch. It was described as the earliest evidence for the subfamily of Ennominae, particularly the tribe Boarmiini.{{cite journal |last1=Fischer |first1=Thilo C. |last2=Michalski |first2=Artur |last3=Hausmann |first3=Axel |year=2019 |title=Geometrid caterpillar in Eocene Baltic amber (Lepidoptera, Geometridae) |journal=Scientific Reports |volume=9 |issue=1 |pages=Article number 17201 |doi=10.1038/s41598-019-53734-w |pmid=31748672|pmc=6868187 |bibcode=2019NatSR...917201F |doi-access=free }}

File:Looper.webm|thumbtime=0 |Locomotion of a looper

File:Geometridae-Dinakarr-10Jun11-DSC 0186.jpg|A geometrid caterpillar camouflaged as a broken twig

File:Geometridae locomotion.jpg|Caterpillar locomotion

File:Synchlora aerata caterpillar.jpg|Synchlora aerata caterpillar dressed with pieces of flowers as camouflage

Geometrid Moths (Geometridae) caterpillar -2.jpg|Geometrid moth (Geometridae) "inchworm" caterpillar

Geometrid Moths (Geometridae) caterpillar.jpg|Geometrid moth (Geometridae) "inchworm" caterpillar

Adults

Many geometrids have slender abdomens and broad wings which are usually held flat with the hindwings visible. As such, they appear rather butterfly-like, but in most respects they are typical moths. The majority fly at night. They possess a frenulum to link the wings, and the antennae of the males are often feathered. They tend to blend into the background, often with intricate, wavy patterns on their wings. In some species, females have reduced wings (e.g. winter moth and fall cankerworm). Most are of moderate size, about {{convert|3|cm|abbr=on}} in wingspan, but a range of sizes occur, from {{convert|10|-|50|mm|abbr=on}}, and a few (e.g., Dysphania species) reach an even larger size. They have distinctive paired tympanal organs at the base of the abdomen (these are absent in flightless females).{{cn|date=November 2019}}

File:Selenia tetralunaria MHNT ventre.jpg|Selenia tetralunaria species from Ennominae

File:Unidentified Moth 0752.jpg|Scopula species

File:Tetracis cachexiata 051712.jpg|Tetracis cachexiata in the US state of Ohio

File:Fall Cankerworm Moth - Alsophila pometaria, Leesylvania State Park, Woodbridge, Virginia.jpg|Alsophila pometaria, wingless adult female

Systematics

{{main|List of geometrid genera}}

The placement of the example species follows a 1990 systematic treatment; it may be outdated. Subfamilies are tentatively sorted in a phylogenetic sequence, from the most basal to the most advanced. Traditionally, the Archiearinae were held to be the most ancient of the geometer moth lineages, as their caterpillars have well-developed prolegs. However, it now seems that the Larentiinae are actually older, as indicated by their numerous plesiomorphies and DNA sequence data. They are either an extremely basal lineage of the Geometridae – together with the Sterrhinae – or might even be considered a separate family of Geometroidea. As regards the Archiearinae, some species that were traditionally placed therein actually seem to belong to other subfamilies; altogether it seems that in a few cases, the prolegs which were originally lost in the ancestral geometer moths re-evolved as an atavism.{{cite journal |last1=Õunap |first1=Erki |last2=Viidalepp |first2=Jaan |last3=Saarma |first3=Urmas |year=2008 |title=Systematic position of Lythriini revised: transferred from Larentiinae to Sterrhinae (Lepidoptera, Geometridae) |journal=Zoologica Scripta |doi=10.1111/j.1463-6409.2008.00327.x |volume=37 |issue=4 |pages=405–413|s2cid=85800529 }}{{cite journal |last=Young |first=Catherine J. |year=2008 |title=Characterisation of the Australian Nacophorini using adult morphology, and phylogeny of the Geometridae based on morphological characters |journal=Zootaxa |volume=1736 |pages=1–141 |doi=10.11646/zootaxa.1736.1.1 |url=http://www.mapress.com/zootaxa/2008/f/z01736p141f.pdf }}

Larentiinae – about 5,800 species, includes the pug moths, mostly temperate, might be a distinct family.

Sterrhinae – about 2,800 species, mostly tropical, might belong to same family as the Larentiinae.

Desmobathrinae – pantropical

Geometrinae – emerald moths, about 2,300 named species, most tropical

Archiearinae – twelve{{Cite web |title=Hemitheini Bruand 1846 - Plazi TreatmentBank |url=https://treatment.plazi.org/id/03B2F2569FFDA4F4E6A7FC5AFC02ABFA/1 |access-date=2024-02-04 |website=treatment.plazi.org |language=en}} species; holarctic, southern Andes and Tasmania, though the latter some seem to belong to the Ennominae, larvae have all the prolegs but most are reduced.

  • Infant, Archiearis infans (Möschler, 1862)
  • Scarce infant, Leucobrephos brephoides (Walker, 1857)

Oenochrominae – in some treatments used as a "wastebin taxon" for genera that are difficult to place in other groups

Alsophilinae – a few genera, defoliators of trees, might belong in the Ennominae, tribe Boarmiini

Ennominae – about 9,700 species, including some defoliating pests, global distribution

  • Eogeometer vadens

Geometridae genera incertae sedis include:

File:Hydriomena? protrita.jpg holotype forewing]]

Fossil Geometridae taxa include:

  • Eogeometer Fischer, Michalski & Hausmann, 2019
  • Hydriomena? protrita Cockerell, 1922 (Priabonian, Florissant Formation, Colorado){{cite journal |last1=Cockerell |first1=T. D. A. |year=1922 |title=A fossil Moth from Florissant, Colorado |journal=American Museum Novitates |issue=34 |pages=1–2 |url=https://books.google.com/books?id=sZNPAAAAYAAJ&q=Hydriomena%22+protrita&pg=PR3}}
  • Geometridites Clark et al., 1971

References

{{Reflist}}

Further reading

  • {{cite book |last=Hausmann |first=A. |year=2001 |title=The Geometrid Moths of Europe |volume=1: Introduction. Archiearinae, Orthostixinae, Desmobathrinae, Alsophilinae, Geometrinae -- v. 4. Larentiinae II (Perizomini and Eupitheciini) |publisher=Apollo Books}}
  • {{cite book |last1=Minet |first1=J. |last2=Scoble |first2=M. J. |year=1999 |chapter=17: The Drepanoid / Geometroid Assemblage |editor-first=N. P. |editor-last=Kristensen |title=Handbuch der Zoologie. Eine Naturgeschichte der Stämme des Tierreiches / Handbook of Zoology. A Natural History of the phyla of the Animal Kingdom. |volume=4: Arthropoda: Insecta. Part 35: Lepidoptera, Moths and Butterflies. Vol. 1: Evolution, Systematics, and Biogeography |publisher=Walter de Gruyter |location=Berlin & New York}}
  • {{citation |editor-last=Scoble |editor-first=M. J. |year=1999 |title=Geometrid Moths of the World: A Catalogue |publisher=CSIRO Publishing |isbn=0-643-06304-8}}