Hydrobiosella arcuata Kimmins
Creators: name: Cartwright, David I.
Publisher: name: Zenodo
Year: 2010
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Trichoptera
Philopotamidae
Hydrobiosella
Hydrobiosella arcuata

description: Hydrobiosella arcuata Kimmins
Figures 1, 23–25, 44–45
Hydrobiosella arcuata Kimmins in Mosely and Kimmins, 1953:
397, fig. 271. — Neboiss, 1986: 103.
Type material (not seen). Holotype. Male, Queensland, Montville, 3 Oct 1912, R. J. Tillyard (BMNH).
Material examined. Queensland. 1 male, Booloumba Ck, 8 km SW Kenilworth, 26°39'S, 152°39'E, 12 Dec 1984, G. Theischinger; 1 male (specimen CT-573 figured), Booloumba Ck, Mary R. catchment, 26°41'S, 152°37'E, 26 Oct 1993, collector unknown; 1 male, 1 female, Branch Ck, Brisbane R. catchment, 26°52'S, 152°41'E, 26 Apr 1993; collector unknown; 1 male, 2 females (specimen CT-603 figured), Stony Ck, Brisbane R. catchment, 26°52'S, 152°43'E, 18 Aug 1992; collector unknown (NMV).
Diagnosis. Hydrobiosella arcuata can be separated from other species in the group by the shape of the harpago, where the ventral margin is curved or arched strongly so that the apex points downwards.
Description. (Revised after Kimmins in Mosely and Kimmins, 1953). Wings similar to other species in the group (fig. 1), length of forewing: male 6.3–7.3 mm, female 6.1–8.0 mm. Forewing fork 2 long, length fork 2 about 1.6 times length of fork 1; length fork 3 about twice length footstalk; fork 4 length about 4.5 times length footstalk. Hind wing fork 1 sessile or with very short footstalk; fork 3 length about 1.0–1.3 times length of footstalk.
Male. Segment IX with shallow notch medially on distal margin in between a pair of small knobs (fig. 25). Segment X with a slender mesal lobe, with a pair of short hairs/bristles subapically, in lateral view slightly downturned distally (fig. 24); in dorsal view not narrowed subapically (fig. 23), with a pair of more pigmented lateral lobes, which terminate in small, slightly backward and outward projecting hooks (figs 23–24). Phallus truncate apically, with a pair of robust parameres arising from the phallus subapically (fig. 24). Inferior appendages in lateral view, with basal segment length about 1.7 times maximum width, broad basally, rounded distally; harpago more slender, with ventral margin sharply angled near middle, curved in distal half with downward pointing acute apex (fig. 24).
Female. Genitalia typical of genus, with a small, shallow, rounded projection on sternite VIII mesodistally (figs 44–45).
Remarks. Males and females of Hydrobiosella arcuata have been collected from five sites in addition to the type locality, all in southeastern Queensland (latitudinal range 26°39'– 26°52'S).
Kimmins’ (in Mosely and Kimmins 1953) and Neboiss’ (1986) figures have been redrawn to allow direct comparisons and to accompany the description that is revised in light of new interpretations of Hydrobiosella genitalic structures.
description: Published as part of Cartwright, David I., 2010, Studies of Australian Hydrobiosella Tillyard: a review of the Australian species of the Hydrobiosella bispina Kimmins group (Trichoptera: Philopotamidae), pp. 1-13 in Memoirs of Museum Victoria 67 on page 9, DOI: 10.24199/j.mmv.2010.67.01, http://zenodo.org/record/8065066