Synocheta Legrand, 1946

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Suggested Common Name: Whisphorns
Number of subordinate taxa: 641 species in 2 superfamilies worldwide, 48 species in both superfamilies in our area.
Etymology: Most likely syn- = together + cheta = [unknown but probably something with the penes], refering to the fused penes of this clade. Common name refers to the almost wispy flagellomeres of members of this group.
Taxonomic History: Synocheta Legrand, 1946; Endophora Verhöeff, 1953
Description: (modified from Tabacaru & Giurginca, 2019) Eyes with 0-3 ommatidia. Antenna 2 flagellomeres 4-6, thin, hyaline, segments often hard to distinguish from each other. Mandible molar present. Maxilla 1 endopod with 3 penicils (=tooth setae). Pereopods 1-7 1-clawed. Stomach superomedianum present. Penes distally fused, resulting in a single spermatophore. Pleon remotor muscles M9, M11 and M13 (controlling the pleopod protopods) with 2 strands. ♂ pleopod 1 protopod with water-conducting scales. ♂ pleopod 2 endopod colinear.
Type taxon: none [functionally Trichoniscoidea Vandel, 1952]
Notes: The two families present in our area are frequently placed in two superfamilies: Stylonicoidea (containing Styloniscidae and 3 extralimital families) and Trichoniscoidea (containing Trichoniscidae and one extralimital family), the key below reflects the differences known between these families. The extralimital family of Trichoniscoidea, Buddelundiellidae, could potentially occur in our regions in greenhouses (Buddelundiella cataractae), it resembles a Buchnerillo but with with a synochetan antenna 2 flagellum and uropods visible dorsally (telson shorter than uropods).
A much smaller clade at an equivalent level, Microcheta, appears to be closer to Synocheta than Crinocheta. It contains one monogeneric family (Mesoniscidae) with two species endemic to the high mountains of Europe.
A genus key to all Synochetans in our area will eventually be developed to facillitate field and photo identifications as well. 

Subordinate taxa: Styloniscidae, Trichoniscidae

Key to families
1 a. Muscles controlling ♂ pleopod 1 very well-developed; Gondwanan, tropical in our region, (Cylindroniscus reaching the S Nearctic in caves and Cordioniscus sometimes appearing in northern greenhouses) (Styloniscoidea) --> Styloniscidae
b. Muscles controlling ♂ pleopod 1 weakly developed; Holarctic, reaching as far south as Mexico and Cuba (Trichoniscoidea) --> Trichoniscidae


Schmidt, C. (2008). Phylogeny of the terrestrial Isopoda (Oniscidea): a review. Arthropod Systematics Phylogeny, 66(2), 191-226.

Tabacaru, I., & Giurginca, A. (2019). Contributions to the study of the Trichoniscidae (Isopoda, Oniscidea). I. Definition and taxonomic position. Travaux de l'Institut de Spéologie “Émile Racovitza", 58:47-63.

Published: Jan 1, 2023
Edited: Apr 1, 2023