Eumastacidae

Burr, 1899

Monkey Grasshoppers, Matchstick Grasshoppers

Genus Guides

Eumorsea(Ball's monkey grasshopper)
Morsea(monkey grasshopper)
Psychomastax(monkey grasshoppers)

is a of grasshoppers commonly known as or matchstick grasshoppers. They are considered primitive within the Orthoptera and are characterized by their distinctive body posture with thin legs held at right angles to the body, often near the horizontal plane. Many are wingless. The family exhibits its greatest diversity in the Neotropics, with most species inhabiting tropical regions. They feed on , ferns, and gymnosperms—ancient plant groups that reflect their primitive evolutionary status.

Morsea kaibabensis by (c) Lon Brehmer, some rights reserved (CC BY), uploaded by Lon Brehmer. Used under a CC-BY license.

Morsea tamalpaisensis by (c) Cricket Raspet, some rights reserved (CC BY), uploaded by Cricket Raspet. Used under a CC-BY license.

Chaparral Monkey Grasshopper imported from iNaturalist photo 166239812 on 7 August 2024 by (c) Daniel S., some rights reserved (CC BY). Used under a CC BY 4.0 license.

Pronunciation

How to pronounce Eumastacidae: /juːˈmæstəsɪˌdiː/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from other by the combination of: legs held at right angles to the body (rather than folded beneath); short with terminal knob; three-segmented ; lack of prosternal spine; and absence of . The posture—angled with vertex projecting above the - line—is also distinctive. Wingless can be confused with nymphs of other families, but features (especially the antennal knob) confirm identity.

Images

Habitat

Primarily tropical , with greatest diversity in Neotropical regions. Specific habitat associations include: Triodia (spinifex) grasslands in arid and semi-arid Australia (for Morabinae); subarboreal environments (for some Geckomima ); and various tropical forest and woodland habitats in Central and South America. The shows broad ecological across tropical and subtropical zones.

Distribution

Widespread in tropical regions worldwide. Primary centers of diversity: Neotropics (Central and South America), with Eumastacinae, Masynteinae, Morseinae, Paramastacinae, Parepisactinae, Pseudomastacinae, and Temnomastacinae largely restricted to South America; Gomphomastacinae in India and central/northeastern Asia; and Morabinae in Australia. Disjunct distribution with Gomphomastacinae as the only non-South American subfamily outside Australia.

Diet

Feeds on , ferns, and gymnosperms—ancient plant groups that reflect the 's primitive evolutionary position within Orthoptera. This dietary specialization on non-angiosperm plants is unusual among grasshoppers and may represent a conserved ancestral trait.

Host Associations

Triodia (spinifex) grasses - /food plantPrimary association for Australian Morabinae in arid and semi-arid grasslands
Gymnosperms - food plantConifers and other gymnosperms form part of the diet
Ferns - food plantPteridophytes are part of the diet
Algae - foodUnusual dietary component among grasshoppers

Ecological Role

Herbivores specializing on ancient plant lineages. Their dietary restriction to gymnosperms, ferns, and suggests they occupy a distinctive with limited competition from more derived that primarily consume angiosperms. Australian Morabinae are significant components of Triodia grassland .

Human Relevance

Minimal direct economic importance. Some Australian (Morabinae) have been subjects of cytogenetic research due to their parthenogenetic and complex systems. The 's primitive characteristics make them of scientific interest for understanding orthopteran evolution.

Similar Taxa

Romaleidae (lubber grasshoppers)Both include flightless, robust-bodied grasshoppers, but Romaleidae have legs folded beneath the body, possess , and have different antennal structure
Acrididae (short-horned grasshoppers)The largest , but Acrididae typically have , different leg posture, and longer without terminal knobs
Tetrigidae (pygmy grasshoppers)Both include small, often wingless , but Tetrigidae have an elongated pronotum extending over the and different leg structure
Chorotypidae and MorabidaeFormerly included as of ; now separate within . Distinguished by various morphological features of genitalia and body structure

More Details

Taxonomic History

The Chorotypidae and Morabidae were formerly treated as within but are now recognized as separate families within the superfamily . This reclassification reflects improved understanding of morphological and evolutionary relationships.

Cytogenetic Significance

The Australian morabine grasshoppers, particularly the virgo group, have been extensively studied for their complex systems and parthenogenetic . Maraba virgo is a permanent parthenogenetic all-female with unique heterozygous chromosome arrangements.

Subfamily Composition

The includes nine recognized : Eumastacinae (Central and South America), Gomphomastacinae (India and central/northeastern Asia), Masynteinae (Cuba), Morseinae (Americas), Paramastacinae (South America), Parepisactinae (South America), Pseudomastacinae (South America), and Temnomastacinae (South America). With the exception of Gomphomastacinae, all non-Australian subfamilies are restricted to South America.

Parasitoid Relationships

Morabinae in Australia are parasitized by braconid wasps in the Notioperilitus (Euphorinae), indicating specific natural enemy associations with this .