aculeus


Also found in: Dictionary, Thesaurus, Wikipedia.

aculeus

[ə′kyü·lē·əs]
(invertebrate zoology)
A sharp, hairlike spine, as on the wings of certain lepidopterans.
An insect stinger modified from an ovipositor.
References in periodicals archive ?
The main differences between the females of both species are the slight difference in the wing pattern and the proportions of all three main parts of the ovipositor (oviscape, inversion membrane and aculeus), which together are inM.
The medial surstylus is apparently used to hold the aculeus when she extends it.
Diagnosis: Species of Pyrgotomyia can be recognized from the other Old World Pyrgotini by a combination of the following: face oblique, concave without medial carina; gena with large subocular sclerite; palp short oval; lateral vertical seta lacking; presternum simple saddle-like, without finger-like lobes; mesonotum with 4-6 dorsocentral setae (including 1 or 2 presutural), 2 pairs of scutellar setae; wing narrow with dorsal surface of vein [R.sub.4 + 5] setulose over all its length, and very short posteroapical lobe of cell bcu; femora without long or thickened setae; oviscape simple, slightly curved dorsally and densely setulose at its apex but bearing no sclerotized hooks; elongate, apically barbed, arrow-like aculeus in female; posteriorly directed finger-like surstyli in male.
The speed with which a scorpion can deliver a sting might be influenced not only by temperature, age, or gender, but also by the starting position of its telson (the last tail segment, to which the aculeus is attached) and its metasoma (tail).
In males, the telson gland is light yellow; slightly pigmented near the lateral margins; ventral and lateral surfaces densely pigmented; aculeus dark brown.
Characters of the females, primarily of the aculeus, and body and wing markings, were considered in identifying species of Anastrepha (Zucchi 2000) identified by Garcia and Zucchi.
The specific name, aculeus, means 'spine' or 'thorn' in reference to the sharp spine-like projections on the apices of the uncal lobes.
Redescription.--Coloration: entire body light yellow or light tan; carapace sometimes with variable dusky markings around median ocular tubercle, interocular triangle and carinae; ocular tubercle dark; telson aculeus and denticles of chelicerae and pedipalp fingers black.
Telson predominantly yellow, brownish basally near the dorsal surface; body of the subaculear tubercle and distal area of the vesicle brown, margins of the subaculear tubercle yellow; aculeus dark-red over almost its entire length, yellow basally.
Telson reddish, darker than segment V and with inconspicuous brownish spots ventroexternally; aculeus dark red, yellowish basally; subaculear tubercle yellowish.