Fergusonina omlandi
Creators: name: Nelson, Leigh A.
name: Scheffer, Sonja J.
name: Yeates, David K.
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Fergusoninidae
Fergusonina
Fergusonina omlandi

description: Fergusonina omlandi Nelson and Yeates sp. nov.
(Figs 1, 2 a–h, 5a–c)
Holotype. 3. AUSTRALIA. New South Wales: Carwoola, Captain’s Flat Road (-35.394417°, 149.377650°, elev. 768 m), S.J. Scheffer & K.E. Omland, 4.ix.2007, from terminal leaf bud gall collected from E. pauciflora.
Paratypes. 7 3, 5 Ƥ. All same label data as holotype (dried type material lodged: ANIC – Australian National Insect Collection, Canberra).
Other material examined. From terminal leaf bud galls collected from E. pauciflora (all in ethanol in ANIC) by S.J. Scheffer & K.E. Omland: AUSTRALIA. Australian Capital Territory: Namadgi National Park, Booth (- 35.734733°, 148.996300°, elev. 973 m), 16.ix.2007. Victoria: 11 km SE Dinner Plain (-37.066033°, 147.340717°, elev. 1293 m), 27.vii.2011: by L.A. Nelson & C.J. Manchester. New South Wales: near Braidwood (-35.443833°, 149.757250°, elev. 683 m), 1.ix.2007; 7 km NE Collector on Federal Highway, Edmonston Rest Area (- 34.894767°, 149.511383°, elev. 762 m), 5.ix.2007; New England National Park, Point Lookout (-30.488650°, 152.408683°, elev. 1547 m), 10.ix.2007; NSW, Ebor, Point Lookout Road (-30.502717°, 152.383750°, elev. 1370 m), 10.ix.2007; Forbes Creek, Forbes Creek Road (-35.429056°, 149.497778°, elev. 573 m).
Diagnosis. Adult. Small (average wing length 2.80 mm), yellow mesopleuron and thorax with 4 dark brownblack vittae. Larva. Dorsal shield with transverse sclerotised bands on each of the mesothorax and metathorax and abdominal segments 1–5. The strongest band is on abdominal segment 1 and prominent dark sclerotised spicules are present on each band.
Description. Adult (Fig. 2 a–h, Table 1). Head as in Figs. 2 a and b. General colour yellow with black markings on abdominal tergites; basal segment of arista light brown, remainder grey; eyes reddish with iridescent green highlights; ocellar triangle brown with black surrounding each ocellus; occiput with feint greyish-brown markings on each side; anterior wall of thorax between postpronotal lobes with a pair of black ‘spots’ separated medially by a thin strip of yellow; thorax with 4 dark brown-black vittae extending from the anterior wall of the thorax posteriorly; lateral vittae extending across postpronotal lobe, slightly interrupted at suture, narrowing thereafter to dorsocentral seta; supraalar area grey-orange; medial dark vittae fused anteriorly extending posteriorly past suture on postsutural scutum level with base of wing, where vittae lighten to grey-brown extending to acrostitial setae; posterior margin of scutum orange; lateral sides of scutellum brown, subscutellum black; thoractic pleurites yellow, mesopleuron yellow; dorsum of abdomen dark grey-black; posterior half of tergite 1 with dark marking, remainder yellow; dark markings on tergites 1 and 2 divided in midline; distal 1/5th of tergite 5 yellow; thin yellow posterior margins on tergites 1–4; abdominal sternites yellow; male epandrium brown.
Setation (all setae black). One pair of short postocellar setae as long as inner vertical seta; outer vertical seta twice as long as inner vertical seta; two differentiated reclinate orbital setae, dorsal one as long as inner vertical seta; most ventral orbital seta two-thirds the length of the dorsal one; parafacial setae short, 22 setae on genae per side; one pair of vibrissae twice as long as parafacial setae. Mesonotum with many short setae; posterior two acrostichal setae and intraalar setae differentiated, each about equal in length, but considerably shorter than posterior dorsocentral and posterior supraalar setae; posterior two dorsocentral setae differentiated, with posterior seta longest; posterior supraalar setae long, about same length as posterior dorsocentrals (about 8× length of undifferentiated mesonotal setae) (following measurements ditto); anterior supraalar seta shorter (3×), a little shorter than presutural seta (as long as intra-alar seta), anterior notopleural seta (1.5× length of supraalar seta), about same length as posterior notopleural seta; differentiated humeral seta as long as anterior notopleural seta; humeral lobe with one long and 3–4 undifferentiated short setae; mesopleuron with 10–16 undifferentiated setae and one long differentiated seta as long as differentiated humeral seta; sternopleuron with 1 long differentiated seta posteriorly and a row of 3–5 undifferentiated setae along dorsal margin; scutellum with two pairs of marginal setae comprising a pair of very long apical setae, and a pair of subapical setae about 0.5× length of apical setae. Abdominal tergites with black setae, longest on lateral margin of each tergite, longest on margins of tergite 5 (as long as subapical scutellar setae); sternites with short black setae in two submedial fields: sternite 2 (3–4 on each field), 3 (5 on each field), 4 (6–8 on each field) and 5 (17–26 on each field). On sternite 5 there are two larger differentiated setae lateral to the submedial field of setae.
Wing (Fig. 2 e, Table 1) distinctly light grey in colour; broadly elongate oval; costa bearing differentiated setae to little beyond R2 + 3; costa very feint beyond R4 + 5; veins R2 + 3 and R4 + 5 divergent to mid-length, parallel beyond; anterior cross vein r-m short, posterior cross vein slightly angled mid-length.
Male postabdomen (Figs. 5 b and c). Epandrium yellow in cleft and dark brown on apex of dorsum graduating to grey-orange towards cerci; epandrium with 20 pairs of setae (including one pair of large differentiated dorsal setae; telomeres hook-shaped; cerci small and articulating with the ventral margin of the epandrium; postgonites with one large distal tooth and approximately 5 submedial setae.
Variation. Male mesonotal markings vary in darkness of pigmentation from very pale orange-brown to dark brown-black. Female as in male, with exceptions; markings variable in width and degree of pigmentation: presutural mesonotum lacking vittae and variable from entirely yellow-orange to markings on anterior wall of thorax extending along anterior margins to postpronotal lobes, thin lateral vittae on scutum posterior to suture extending towards scutellum ending between the intraalar seta and dorsocentral seta with prescutellar area orange, scutum with dark ‘spots’ anteromedial to and one third the length of lateral vittae. Female abdomen similar to male except for elements of the ovipositor (segment 6 to end; Fig. 5 a); segment 6 largely dark brown-black with posterior margin orange; apex of segment 6 with a row of 6 dorsal, and a row of 6 ventral setae; segment 7 short, with 4 scattered dorsal and 4 ventral setae.
Mature third instar larva (Fig. 2 g). Similar to other Fergusonina larvae. Length 1.00– 2.50 mm, width 0.45– 1.30 mm (n = 34, specimens in ethanol); shape ovate-pyriform; cephalothorax strongly sclerotised, anterior and posterior spiracles strongly sclerotised, abdomen with 9 visible segments; dorsal shield comprising separate transverse sclerotised bands with prominent dark sclerotised spicules on each of the mesothorax and metathorax and abdominal segments 1–5. Some larvae display a few feint spicules on abdominal segment 6. The bands vary in width and extent of sclerotisation with the strongest band on abdominal segment 1.
Puparium (Fig. 2 h). Puparium barrel-shaped, smooth, brown, annulated, bearing dorsal shield (see description of larva). Measurements as in Table 1.
Etymology. This species is named after Dr Kevin Omland who, together with Dr Sonja Scheffer, found and collected it across its known range.
Fergusonina Larvae Pupae
sp. nov. n Length Width n Length Width
Mean Range Mean Range Mean Range Mean Range
williamensis 3 2.10 ± 0.40 1.60–2.90 1.33 ± 0.17 1.00–1.50 4 1.96 ± 0.11 1.64–2.10 1.90 ± 0.37 1.20–2.60
omlandi 34 1.49 ± 0.07 1.00–2.50 0.94 ± 0.04 0.45–1.30 19 2.02 ± 0.05 1.70–2.35 1.16 ± 0.03 0.90–1.35
thornhilli n/a 7 2.40 ± 0.08 2.00–2.60 1.43 ± 0.05 1.25–1.5 Comments. Fergusonina omlandi is similar in size to Fergusonina taylori Nelson & Yeates, one of two sympatric species described previously from the snow gum complex (Nelson et al., 2011). However, it differs in possessing well separated mesonotal markings and in the morphology of the male and female genitalia. The larval dorsal shield pattern of F. omlandi is also subtly different, possessing 7 sclerotised bands in contrast to the 9 bands seen in the larvae of the other two species. So far, F. omlandi has only been collected from snow gums at lower altitudes (the highest record is 1547 m at New England National Park, NSW).
description: Published as part of Nelson, Leigh A., Scheffer, Sonja J. & Yeates, David K., 2011, Three new species of Fergusonina Malloch gall-flies (Diptera: Fergusoninidae) from terminal leaf bud galls on Eucalyptus (Myrtaceae) in south-eastern Australia, pp. 36-48 in Zootaxa 3112 on pages 39-40, DOI: 10.5281/zenodo.207304