Terellia (Cerajocera) gynaecochroma (Hering, 1936)

Troshyn, A. M., 2024, Description Of The Third Instar Larvae Of Terellia Tussilaginis And T. Gynaecochroma (Diptera, Tephritidae), Zoodiversity 58 (2), pp. 167-174 : 170-173

publication ID	https://doi.org/ 10.15407/zoo2024.02.167
persistent identifier	https://treatment.plazi.org/id/70141B04-2274-5D67-FF56-38B8FD113602
treatment provided by	Felipe
scientific name	Terellia (Cerajocera) gynaecochroma (Hering, 1936)
status

Treatment

Terellia (Cerajocera) gynaecochroma (Hering, 1936) View in CoL ( figs 3–4 View Fig View Fig )

Orellia lappae , Terellia (Cerajocera) lappae : auctt.

M a t e r i a l e x a m i n e d. Ukraine, Kryviy Rih District, in lateral stems of Onopordum acanthium L.,

4.01.2024, 5 third instar larvae (A. Troshyn leg.).

Description. Third instar larva. Body is elongated oval; 4.71–5.54 mm long (mean 5.2); 1.51–2.0 mm wide (mean 1.8); 2.61–2.9 times as long as wide (mean 2.77). Coloration. The body is light yellow. Posterior surface of segment 8 orange to reddish brown.

Gnathocephalon ( fig. 3 View Fig , 4 View Fig ) mostly smooth, inverted into thoracic segment 1 at rest. Anterior sensory lobes short, partly separated at anterior margin. Antenna (dorsal sensory organ) ( fig. 3 View Fig , 4 View Fig : ant) with short, rounded terminal segment. Medial sensory organ ( fig. 3 View Fig , 5: mso) hidden in median groove, but rather distinct. Anterior portion of sensory lobe with network of grooves. Antero-lateral portion of gnathocephalon with 10–12 oral ridges ( fig. 3 View Fig , 4 View Fig : or rdg). Lateral sensory organ ( fig. 3 View Fig , 5: lso) distinct. Stomal sensory organ ( fig. 3 View Fig , 5: sto org) small, round, without lobes or teeth. Lateral surface of anterior sensory lobe and gnathocephalon posterior of oral ridges with network of anastomosing grooves, more expressed than in T. (C.) tussilaginis . Labial lobe not examined. Postero-lateral portion of gnathocephalon with rather numerous small and acute denticles.

Cephalopharyngeal skeleton ( fig. 3 View Fig , 6). Mandibular sclerite ( fig. 3 View Fig , 6: msc) oblong, with simple blunt mouthhook ( fig. 3 View Fig , 6: mhk) and without additional lobes or teeth. Preapical tooth ( fig. 3 View Fig , 6: pt) at most vestigial, barely visible; dorsal and ventral apodemes ( fig. 3 View Fig , 6: da, va) about as high as long. Hypopharyngeal sclerite ( fig. 3 View Fig , 6: hs) moderately long, ca. two times as long as high, parastomal sclerite fused to it, indistinct. Dental and labial sclerite not expressed. Pharyngeal sclerite and dorsal and ventral cornu (fig. 2, 1: dc, vc) visible, but details not clear.

Thoracic segments 1–3 moderately sclerotised. Segment 1 short, forming a shield-like “mask” ( fig. 3 View Fig , 4 View Fig , 5) with T-shaped aperture; antero-dorsal surface without spinules. Anterior spiracle ( fig. 4 View Fig , 1 View Fig ) with 8 lobes. Segments 2–3 almost smooth, with rows of denticles at anterior margins.

Abdominal segments 1–7 with papillae on lateral and ventrolateral surfaces. Creeping welts present on abdominal segments, more obvious ventrally, each creeping welt composed of several rows of spinules with truncate apex and rounded perimeter, but sometimes slightly pointed.

Segment 8 ( fig. 4 View Fig , 2) without plaques at anterodorsal margin. Stigmatal area with slightly elevated stigmatal plates separated with area 0.5 times as wide as spiracular plate and bearing 4–5 polygonal or oval plaques. Ventral sensillum ( fig. 4 View Fig , 2: V1) and intermediate sensilla ( fig. 4 View Fig , 2: I1, I2 and I3) present, close to each other. Other sensilla to be expected not visible, maybe due to contaminations. On the ventral side there is a sclerotized prominence ( fig. 4 View Fig , 2: sp).

Posterior spiracle ( fig. 4, 4 View Fig ) with three spiracular slits. Dorsal slit almost horizontal. Ventral slit almost vertical, forming angle 95–105° to dorsal slit. Bundles (from dorsal to medioventral) with 2–2–2–1 lanceolate, flattened spiracular hairs ( fig. 4, 4 View Fig : sh).

Diagnosis. Third instar larva of T. (C.) gynaecochroma differs from all known larvae of Terelliini except T. (C.) plagiata (Dahlbom, 1850) , T. (C.) ceratocera (Hendel, 1913) , T. (C.) clarissima Korneyev, 1987 and T. (C.) cyanoides Korneyev, 2003 by the presence of a sclerotised prominence of the abdominal segment 8.

Terellia (Cerajocera) gynaecochroma differs by the single simple conical shape of the sclerotised prominence of 8th segment from T. (C.) plagiata and T. (C.) ceratocera , which are double or simple bifurcated in those species, respectively ( Persson, 1963). Terellia (C.) clarissima and T. (C.) cyanoides also have the prominence single and simple, but there is no detailed description of their larvae.

Notes. T. (C.) gynaecochroma is widespread in Central and Eastern Europe, and apparently in Israel ( Freidberg & Kugler, 1989), Turkey ( Kütük & Yaran, 2011 and Iran ( Mohamadzade & Korneyev, 2018). Larvae develop in flower heads, and at the 3rd instar, in the lateral stems of Onopordum acanthium ( Korneyev, 1987) .

Acknowledgements

I would like to express my sincere gratitude to Valery A. Korneyev for the invaluable assistance, important advice and kind sharing of his skills in preparing slides and digital photographs of larvae. The work is a part of a PhD study at the I. I. Schmalhausen Institute of Zoology of the National Academy of Sciences of Ukraine.

The author is grateful to two anonymous reviewers, whose comments have significantly improved the quality of the article.

The research leading to this publication has received funding from the I. I. Schmalhausen Institute of Zoology NAS of Ukraine project No III-50-21, 0121U107752.

Author has no potential sources of conflict of interests.