'''Sprindžiai''' (lot. ''Geometridae'') – drugių (''Lepidoptera'') šeima, kuriai priklauso vidutiniai ir smulkūs drugiai, kurių kūnas plonas, grakštus, sparnai stambūs ir ploni, ant nugaros susiglaudžia lėkštai. Priekinių sparnų piešinys smulkus, sudarytas iš taškelių, dėmelių ar plonų skersinių linijų. Užpakalinių sparnų piešinys dažnai toks pat, kaip ir priekinių. Straublelis normalus. Patelių antenos siūliškos, patinų plunksniškos. Kai kurios patelės besparnės. Drugiai skraido ne tik naktimis, bet ir dienomis, ypač miškuose. Vikšrai pliki, turi 10 kojų, rėplioja sprindžiuodami.

Lietuvoje yra apie 320 rūšių. Tarp jų yra svarbių sodų ir miškų kenkėjų.

== Lietuvos sprindžiai ==
*Pošeimis. Pavasariniai sprindžiai (''Archiearinae'')
**Paprastasis pavasarinukas (''Archiearis parthenias'')
**Retasis pavasarinukas (''Archiearis notha'')

*Pošeimis. Žievėsprindžiai (''Ennominae'')
**Agrastinis margasprindis (''Abraxas grossulariata'')
**Miškinis margasprindis (''Calospilos sylvata'')
**Paprastasis margasprindis (''Lomaspilis marginata'')
**Šiaurinis margasprindis (''Lomaspilis opis'')
**Ožekšninis margasprindis (''Ligdia adustata'')
**Rudlankis sprindžius (''Stegania cararia'')
**Smiltyninis margenis (''Heliomata glarearia'')
**Balsvasis miškasprindis (''Macaria notata'')
**Pilkasis miškasprinis (''Macaria alternata'')
**Eglinis miškasprindis (''Macaria signaria'')
**Pušinis miškasprindis (''Macaria liturata'')
**Pilkasis serbentinis sprindis (''Macaria wauaria'')
**Gluosniasprindis (''Macaria artesiaria'')
**Lietuvos raudonąją knygą. 
**Tinklasprindis (''Chiasmia clathrata'')
**Mažasis smėlinukas (''Narraga fasciolaria'')
**Rudasis mėlyninis sprindžius (''Itame brunneata'')
**Šiaurinis pilkasis sprindžius (''Itame loricaria'')
**Gelsvasis smilčiasprindis (''Tephrina arenacearia'')
**Gelsvasis miškasprindis (''Cepphis advenaria'')
**Papartinis sprindžius (''Petrophora chlorosata'')
**Avietinis sprindžius (''Plagodis pulveraria'')
**Siaurasparnis sprindžius (''Pachycnemia hippocastanaria'')
**Geltonasis sprindžius (''Opisthograptis luteolata'')
**Gluosninis dvispalvis sprindžius (''Epione repandaria'')
**Beržinis dvijuostis sprindžius (''Epione vespertaria'')
**Leopardinis sprindžius (''Pseudopanthera macularia'')
**Gelsvasis sprindžius (''Hypoxystis pluviaria'')
**Puošniasprindis (''Apeira syringaria'')
**Didysis geltonsprindis (''Ennomos autumnaria'')
**Lietuvos raudonąją knygą. 
**Alksninis geltonsprindis (''Ennomos alniaria'')
**Rudasparnis geltonsprindis (''Ennomos fuscantaria'')
**Ąžuolinis geltonsprindis (''Ennomos erosaria'')
**Pilkšvasis mėnuliasprindis (''Selenia dentaria'')
**Gelsvasis mėnuliasprindis (''Selenia lunularia'')
**Rausvasis mėnuliasprindis (''Selenia tetralunaria'')
**Ožekšninis sprindžius (''Artiora evonymaria'')
**Dvidantis sprindžius (''Odontopera bidentata'')
**Geltonasis dvijuostis sprindžius (''Crocallis elinguaria'')
**Gelsvoji jaunamartė (''Ourapteryx sambucaria'')
**Rudasis rudeninis sprindžius (''Colotois pennaria'')
**Slyvinis sprindžius (''Angerona prunaria'')
**Pietinis šeriasprindis (''Apocheima hispidaria'')
**Sniegsprindis (''Apocheima pilosaria'')
**Miškinis šeriasprindis (''Lycia hirtaria'')
**Laplandis šeriasprindis (''Lycia lapponaria'')
**Skaidriasparnis šeriasprindis (''Lycia pomonaria'')
**Drebulinis šeriasprindis (''Biston strataria'')
**Beržinis šeriasprindis (''Biston betularia'')
**Mažasis ankstyvasis sprindžius (''Agriopis leucophaearia'')
**Auksasprindis (''Agriopis  aurantiaria'')
**Gelsvasis ankstyvasis sprindžius (''Agriopis marginaria'')
**Žiemsprindis (''Erannis defoliaria'')
**Dvijuostis žievėsprindis (''Synopsia sociaria'')
**Grakštusis žievėsprindis (''Peribatodes secundaria'')
**Stepinė selidozema (''Selidosema brunnearia'')
**Pavasarinis žievėsprindis (''Cleora cinctaria'')
**Pilkrudis žievėsprindis (''Deileptenia ribeata'')
**Tamsiajuostis žievėsprindis (''Alcis repandata'')
**Bastelbergerio žievėsprindis (''Alcis bastelbergeri'')
**Ilgakerpinis žievėsprindis (''Alcis jubata'')
**Pelkinis margasprindis (''Arichanna melanaria'')
**Didysis žievėsprindis (''Hypomecis roboraria'')
**Pilkasis žievėsprindis (''Hypomecis punctinalis'')
**Kerpinis žievėsprindis (''Cleorodes lichenaria'')
**Mėlyninis žievėsprindis (''Ectropis crepuscularia'')
**Dėmėtasis žievėsprindis (''Paradarisa consonaria'')
**Rudasis žievėsprindis (''Parectropis similaria'')
**Mažasis žievėsprindis (''Aethalura punctulata'')
**Rudasprindis (''Ematurga atomaria'')
**Mažasis sprindžius (''Tephronia sepiaria'')
**Pušinis sprindžius (''Bupalus piniaria'')
**Pilkajuostis balsvasprindis (''Cabera pusaria'')
**Pilkakraštis balsvasprindis (''Cabera leptographa'')
**Rudjuostis balsvasprindis (''Cabera exanthemata'')
**Dvitaškis balsvasprindis (''Lomographa bimaculata'')
**Pilkadėmis balsvasprindis (''Lomographa temerata'')
**Žalsvasis sprindžius (''Campaea margaritata'')
**Raudonsprindis (''Hylaea fasciaria'')
**Viržyninis pilkasprindis (''Gnophos obfuscata'')
**Smiltyninis pilkasprindis (''Charissa obscurata'')
**Pušyninis pilkasprindis (''Charissa ambiguata'')
**Šiaurinis pilkasprindis (''Elophos vittaria'')
**Gyslotasis sprindžius (''Siona lineata'')
**Lietuvos raudonąją knygą.
**Lietuvos raudonąją knygą.
**Viržiasprindis (''Perconia strigillaria'')

*Pošeimis. Ankstyvieji sprindžiai (''Oenochrominae'') 
**Rudasparnis ankstyvasis sprindžius (''Epirranthis diversata'')
**Ankstyvasis sprindžius (''Alsophila aescularia'')

{{Taxobox
| name = Geometridae
| image = Scopula imitaria01.jpg
| image_width = 240px
| image_caption = Small Blood-vein, ''Scopula imitaria''<br />(Sterrhinae: Timandrini)<br/>Photo from [http://www.entomart.be/ entomart.be]
| regnum = Animalia
| phylum = Arthropoda
| subphylum = Hexapoda<!-- outcomment unnecessary taxa instead of deleting them. They may eventually be included again when the article grows longer. -->
| classis = Insecta
| subclassis = Pterygota
| infraclassis = Neoptera
| superordo = Endopterygota
| ordo = Lepidoptera
| unranked_familia = Macrolepidoptera
| superfamilia = Geometroidea
| familia = '''Geometridae'''
| familia_authority = Leach, 1815<!-- "Stephens, 1829"? -->
| type_species = ''Geometra papilionaria''
| type_species_authority = Linnaeus, 1758
| diversity = About 2,000 genera<br>> 26,000 species
| diversity_link = list of geometrid genera
| subdivision_ranks = Subfamilies
| subdivision = 
Alsophilinae <small>(disputed)</small><br><!-- Zootaxa1736:1 -->
Archiearinae<br><!-- Zootaxa1736:1 -->
Desmobathrinae<br>
Ennominae<br>
Geometrinae<br>
text)</small><br>
Oenochrominae<br><!-- Zootaxa1736:1 -->
Orthostixinae<br>
Sterrhinae
}}

The '''geometer moths''' or '''Geometridae''' are a family of the order pests.

==Adults==
Many Geometrids have slender antennae of the males are often feathered. They tend to blend in to 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 3 cm in wingspan, but a range of sizes occur. They have distinctive paired tympanal organs at the base of the abdomen (lacking in flightless females).

==Caterpillars==
thumb|left|Caterpillar locomotion
The name "Geometridae" ultimately derives from ''geometer'' ("earth-measurer"). This refers to the means of locomotion of the larvae or caterpillars, which lack most of the prolegs of other Lepidopteran caterpillars. Equipped with appendages at both ends of the body, a caterpillar will clasp with its front legs and draw up the hind end, then clasp with the hind end (prolegs) and reach out for a new front attachment - creating the impression that it is measuring its journey. The caterpillars are accordingly called '''loopers''', '''spanworms''', or '''inchworms'''. They tend to be green, grey, or brownish and hide from predators by fading into the background or resembling twigs. Some have humps or filaments (see Filament-bearer image). They are seldom hairy or gregarious. Typically they eat leaves. However, some eat lichen, flowers or pollen. Some, such as the Hawaiian species of the genus ''Eupithecia'', are even carnivorous.

== Systematics ==
The placement of the example species follows a 1990 systematic; it may be outdated. Families are tentatively sorted in a basal to the most advanced. Traditionally the basal lineage of the Geometridae &ndash; together with the 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.<ref name = young2008>Young (2008)</ref>.

Larentiinae - about 5,700 species, includes the pug moths, mostly temperate. Might be a distinct family<ref name = young2008 />.

Sterrhinae - about 2,800 species, mostly tropical
* Birch Mocha, ''Cyclophora albipunctata''
* False Mocha, ''Cyclophora porata''
* Maiden's Blush, ''Cyclophora punctaria''
* Riband Wave, ''Idaea aversata''
* Small Fan-footed Wave, ''Idaea biselata''
* Single-dotted Wave, ''Idaea dimidiata''
* Small Scallop, ''Idaea emarginata''
* ''Idaea filicata''
* Rusty Wave, ''Idaea inquinata''
* Purple-bordered Gold, ''Idaea muricata''
* Bright Wave, ''Idaea ochrata''
* Least Carpet, ''Idaea rusticata''
* Small Dusty Wave, ''Idaea seriata''
* Cream Wave, ''Scopula floslactata''
* Zachera Moth, ''Semiothisa zachera''
* Blood-vein, ''Timandra comae''
* Eastern Blood-vein, ''Timandra griseata''

Desmobathrinae - pantropical

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

Archiearinae - 12 species; Holarctic, southern Andes and Tasmania, though the latter some seem to belong to the Ennominae<ref name = young2008 />. Larvae have all the prolegs except most are reduced.
* The Infant, ''Archiearis infans'' <small>(Möschler, 1862)</small>
* Scarce Infant, ''Leucobrephos brephoides'' <small>(Walker, 1857)</small>