Dasyhelea (Dasyhelea) quasifulcillata, Brahma & Chatterjee & Hazra, 2023

Brahma, Shubhranil, Chatterjee, Somnath & Hazra, Niladri, 2023, Five new Indian species of the genus Dasyhelea Kieffer (Diptera, Ceratopogonidae) with a key to the adult males, Evolutionary Systematics 7 (1), pp. 51-66 : 51

publication ID

https://dx.doi.org/10.3897/evolsyst.7.90973

publication LSID

lsid:zoobank.org:pub:15FBAE73-903B-4E14-BDE3-CCC2D65AAD81

persistent identifier

https://treatment.plazi.org/id/54053E58-FB6F-4BE4-A02D-161D8880D2D0

taxon LSID

lsid:zoobank.org:act:54053E58-FB6F-4BE4-A02D-161D8880D2D0

treatment provided by

Evolutionary Systematics by Pensoft

scientific name

Dasyhelea (Dasyhelea) quasifulcillata
status

sp. nov.

Dasyhelea (Dasyhelea) quasifulcillata sp. nov.

Type material.

Holotype ♂, India, West Bengal, Purba Bardhaman, Burdwan [23°15'03.8"N, 87°50'45.1"E], 11.IV.2017, Coll. S. Brahma. Paratypes: 2♂♂, data same as before, except 20.IV.2018; 2♂♂, India, West Bengal, Birbhum, Narayanpur [24°14'40.6"N, 87°41'30.7"E], 8.II.2017, Coll. S. Chatterjee.

Diagnosis.

The only species in the subgenus Dasyhelea Dasyhelea diagnosed by a vertical unsclerotised region in frontal sclerite; gonocoxite with two long apical setae ventrally; posteromedian projection of parameres broad, blade like; posterolateral arm of aedeagus with flap like extensions inwardly directed.

Description.

Male adult (n = 5) (Figs 4A-K View Figure 4 , 8B View Figure 8 ). Total body length 1.8-1.9 (1.85) mm.

Head. Dark brown in colour. Eyes separated by one fourth of diameter of an ommatidium. Frontal sclerite (Fig. 4A View Figure 4 ) 57-58 (57.5) μm long and 54-56 (55) μm wide, hyperbolic, evenly sclerotised, except mid vertical line, with a minute apical projection. Antennal flagellum (Fig. 4B View Figure 4 ) pale brown, 0.50-0.6 (0.55) mm long; XIII with a distinct apical projection; length ratio of flagellomeres (I-XIII): 18 (18): 11-13 (12): 11-13 (12): 11-13 (12): 11 (11): 12 (12): 12 (12): 12 (12): 12 (12): 24-25 (24.5): 23 (23): 18-19 (18.5): 35-36 (35.5); AR 1.00 (1.00); flagellomeres II-XIII with sensilla basiconica. Clypeus (Fig. 4C View Figure 4 ) with 4 pairs of setae. Palpus (Fig. 4D View Figure 4 ) pale; length ratio of palp segments (I-V): 9 (9): 11-12 (11.5): 20 (20): 12 (12): 14-15 (14.5); PR 2.2 (2.2); palp segment III with 2 capitate sensilla at lower half region.

Thorax (Fig. 4E View Figure 4 ). Brown in colour without any prominent infuscation. Acrostichals with 9-10 pairs, irregularly biserial; dorsocentrals 8-9 pairs, irregularly biserial; prealars 7, uniseral; scutellum with 5 setae.

Wing (Fig. 4F View Figure 4 ). Wing margin with short, prominent macrotrichia; r5 with macrotrichia at anterior region. WL 0.90 (0.90) mm, WW 0.30-0.32 (0.31) mm, CR 0.45 (0.45). Cubital fork present before costal extremity.

Legs (Fig. 4G View Figure 4 ). Pale in colour, mid region of fore, mid and hind femora, and fore and mid tibiae prominently infuscated, hind tibia with diffused infuscation. Hind tibial comb (Fig. 4H View Figure 4 ) with 8 spines. TRI 2.83-3.16 (3.01), TRII 2.85-3.45 (3.14) and TRIII 2.61-3.00 (2.73).

Abdomen. Brown in colour.

Genitalia (Figs 4I View Figure 4 , 8B View Figure 8 ). Tergite 9 broad apically, inverted dome shaped, 120-122 (121) μm long and 224-225 (224.5) μm wide anteriorly, 50-51 (50.5) μm wide posteriorly. Apicolateral processes (Fig. 4J View Figure 4 ) 11-12 (11.5) μm long with one prominent apical seta, cercus setose with median sized setae. Sternite 9 4.81 × wider than length, with a middle concave excavation. Gonocoxite stout, elongated, 89-90 (89.5) μm long, greatest width 55 (55) μm. Gonostylus long, gradually tapering, 82-83.5 (83) μm in length, 18-19 (18.5) μm wide basally and 6 (6) μm wide apically; one distinct seta at mid length, distal one fifth region containing two prominent stout setae, subapex bearing 2 setae dorsally and one seta ventrally. Parameres thin, highly sclerotised (Fig. 4I View Figure 4 ) with left basal arm 78-79 (78.5) μm long, joined moderately with posteromedian projection; right basal arm 53-54 (53.5) μm long; posteromedian projection 107-108 (107.5) μm long, 25-26 (25.5) μm wide medially, bladelike, moderately sclerotised, terminating in a point beyond gonocoxite-gonostylus junction. Aedeagus (Fig. 4K View Figure 4 ) broad, 69 (69) μm long, 82-83 (82.5) μm wide, basal arm 32-33 (32.5) μm long, highly sclerotised, directed laterad; basal arch 44-45 (44.5) μm long; posterolateral arm 46 (46) μm long, stout with flaplike inward projection.

Female adult. Unknown.

Pupa and Larva. Unknown.

Etymology.

The name " Dasyhelea quasifulcillata " refers to its close similarity with allied species, D. (Dasyhelea) fulcillata Yu, 2005.

Remarks.

The new species resembles Dasyhelea (Dasyhelea) fulcillata Yu in Yu et al. 2005 (China) in the shape of the both basal arms of parameres, posteromedian projection of parameres and basal arm of aedeagus, but it differs in the margin of sternite 9, the apex of gonostylus, the absence of prominent seta at about mid length of gonostylus, basal arch and apex of posterolateral arm of the aedeagus. Dasyhelea (D.) neofusca Yu in Yu et al. 2005 (China) also has similar shaped parameres and margin of sternite 9, but the structure of the apicolateral process, the gonostylus and the aedeagus are contrasting. Dasyhelea bilineata Goetghebuer, 1920 (Belgium, Russia, Norway, Finland, Estonia, Great Britain, Ireland, Hungary, Germany, Poland, Czech Republic, Slovakia, Switzerland, Austria, France, Croatia, Italy, Romania, Ukraine, Spain, Turkey, Gibraltar, Bulgaria, and Algeria) bears little similarity with D. (D.) quasifulcillata sp. nov. in overall structure of the gonocoxite and aedeagus, while the basal arm of the aedeagus and the shape of the parameres differ from each other. The present species shares resemblances with D. (D.) flavifrons ( Guérin-Méneville, 1833) (France, Belgium, Estonia, Germany, Poland, Great Britain, Czech Republic, Switzerland, Austria, Croatia, Spain, Bulgaria, Greece, Russia, Ukraine, and USA) in parameres, but apical portion of gonostylus, basal arms, and basal arch of the aedeagus markedly differ. Dasyhelea (D.) malleola Remm, 1962 (Estonia, Spain, Andorra, Poland, Germany, Czech Republic, Ukraine, and Algeria) has identical basal arms of the parameres, but the posteromedian projection of the parameres, apex of the gonostylus and posterolateral arm of the aedeagus are opposing with those of D. quasifulcillata . However, the combination of characters provided in the diagnosis validates D. (D.) quasifulcillata as a new member of this subgenus.

Distribution.

The specimens were collected from the Deltaic Proper of Gangetic West Bengal at an altitude 30-42 meters above sea level - new species from India.

Ecological notes.

Dasyhelea (D.) quasifulcillata sp. nov. adults were captured around shrub vegetation and paddy field area adjoining a freshwater river (Fig. 2B View Figure 2 ) when the air temperature was 27-35 °C and relative humidity was 70-75%.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Ceratopogonidae

Genus

Dasyhelea