Odiellus

Members of Odiellus can be distinguished from other Phalangiidae by their relatively short legs and often flattened body profile. Odiellus spinosus specifically displays a prominent trident of three large spines anterior to the eyes. Many species exhibit granular or spiny body surface textures. Detailed species-level identification requires examination of genitalia and other fine morphological characters.

Species occupy varied habitats from natural to synanthropic environments. Odiellus spinosus in its native range prefers dry open areas such as sand-dunes; in introduced regions it occurs in gardens, parks, railway embankments, and near buildings. Eggs are laid beneath decaying wood, leaf litter, rocks, or garden vegetation.

Native to southern Europe. Odiellus spinosus has been introduced to and is expanding in northern Europe including UK, Belgium, Denmark, Germany, Netherlands, Poland, Sweden, and Switzerland. GBIF records indicate presence in Denmark, Norway, Sweden, and Vermont, USA.

Odiellus spinosus exhibits a one-year life cycle with adults active August–October. Eggs hatch late January through March, with juvenile development February–July. Adult mortality occurs by December.

Odiellus spinosus completes development in approximately one year. Eggs overwinter without diapause and hatch over an extended period of several months. Juveniles develop for six months before maturing. Adults live approximately three months. Females lay two batches of eggs with 16–27 days between batches, producing a mean of 245 eggs (maximum 318). Eggs are large (up to 1.4 mm diameter) and laid in sheltered locations rather than buried.

Males possess a 4 mm penis for direct insemination. Females have ovipositors extending up to 1.45 times body length, an adaptation for egg placement in concealed microhabitats.

Odiellus spinosus has become established in urban and suburban environments in northern Europe, occurring in gardens and parks. The species was selected for genome sequencing as part of the Darwin Tree of Life Project, yielding a 443.70 Mb genome assembly.

• PhalangiumAlso in Phalangiidae with long legs; Odiellus species have proportionally shorter legs and often more pronounced body spination or granulation.
• OligolophusCongeneric in Oligolophinae; requires examination of pedipalps, ocular tubercle structure, and male genitalia for reliable separation.

• harvestmen
• Phalangiidae
• European fauna
• introduced species
• genome sequenced
• urban ecology

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• The genome sequence of the harvestman spider, Odiellus spinosus (Bosc, 1792).