Styringomyia LOEW , 1845

Theischinger, Günther, D, Zacariah & Martin, John, 2018, The genus Styringomyia LOEW in Australia (Diptera: Tipuloidea: Limoniidae), Linzer biologische Beiträge 50 (2), pp. 1587-1633 : 1588-1589

Genus Styringomyia LOEW, 1845

Styringomyia LOEW, 1845: 6 .

Type-species: Styringomyia venusta LOEW, 1845, by monotypy. Descriptive note in EDWARDS, 1911b.

Styringia BERENDT, 1845: 57. Nomen nudum.

Idiophlebia GRÜNBERG, 1903: 524. Type-species: Idiophlebia pallida GRÜNBERG, 1903 (= Styringomyia didyma GRIMSHAW, 1901 ), by monotypy.

Pycnocrepis ENDERLEIN, 1912: 65. Type-species: Pycnocrepis annulipes ENDERLEIN, 1912, by original designation.

Mesomyites COCKERELL, 1917: 377. Type-species: Mesomyites concinna COCKERELL, 1917, by monotypy.

Syringomyia ALEXANDER, 1972: 841. Unjustified emendation of Styringomyia .

D i a g n o s i s. Adult ( Figs 1 -4)

Detailed and accurate redescriptions of the diagnostic features of adult Styringomyia were made available by EDWARDS (1914, 1924) and ALEXANDER (1972). Emphasizing the morphology of the Neotropical species, RIBEIRO (2003) presented even more elaborate and useful descriptions. His terminology for morphological details of wing and terminalia ( RIBEIRO 2003: Figs 7-9 and 27-29 ) is closely followed in this paper. For the present treatment diagnostic characters are given that enable identification of Styringomyia from all genera of Limoniidae known from Australia. These characters follow those presented in the key to Australian Limoniidae by THEISCHINGER (1996).

Front of head only moderately produced; rostrum shorter than remainder of head; antennae 16-segmented; eyes glabrous. Wing: Sc1 short, shorter than 1/2 length of wing; 3 branches of R reaching wing margin; Rs with 2 branches, anterior branch ending well before 2/3 length of wing; discal cell closed, quadrilateral or pentagonal; r-m not in alignment with Rs; CuA2 not fused with A1. The male terminalia are torted at 180 degrees, such that the abdominal sternite 9 occupies a dorsal position and tergites 9 and 10 occupy a ventral position. This torsion is not diagnostic for Styringomyia but found in a series of Chioneinae genera. The female terminalia are not torted and are, according to species group and species, highly variable.

Larva (Figs 5, 6)

The most comprehensive account of the immature stages of Styringomyia is given by HYNES (1990), in which the larva and pupa of Styringomyia neocaledoniae ALEXANDER, 1948 , from New Caledonia are described and figures of key characters are provided.

The larva of S. neocaledoniae possesses a spiracular disk with seven fleshy lobes, three smaller dorsal, two larger lateral and two ventrolateral ( HYNES 1990). In the absence of larval specimens of any other species this can only be assumed to be the common state for the genus. According to OOSTERBROEK & THEOWALD (1991) a seven lobed spiracular disk is seen in only one other genus, Gonomyodes ALEXANDER, 1948 , however in this case the lobes are all of approximately equal size.

With respect to larval ecology, ALEXANDER (1919), EDWARDS (1924) and HYNES (1990) state that larvae of Styringomyia inhabit decaying organic materials such as wet leaf litter, fallen timber, banana fibres or palm fronds.

During examination of thousands of larvae of Australian Tipuloidea, forms with a seven lobed spiracular disk were not encountered. However, larvae examined have predominantly been from aquatic habitats or inundated soils, whereas habitats as described above were hitherto not targeted.

Figures

Figs 1, 2: Styringomyia sp., male, habitus plus inset hypopygium: (1) S. baroalba nov.sp.; (2) S. collessi nov.sp.

Figs 7-12: Styringomyia bancrofti EDWARDS: (7-9) terminalia, modified from EDWARDS (1924): (7, 8) male: (7) ventral; (8) dorsal; (9) female dorsal; (10-12) paratype male: (10) wing; (11) terminalia, ventral; (12) label.

Figs 26-29: Styringomyia terraereginae ALEXANDER, holotype male: (26) wing; (27) terminalia, ventral; (28) leg; (29) label.