Culex (Culex) gaugleri, Suman & De & Sharma & Chandra & Banerjee, 2021

Suman, Devi Shankar, De, Souvik, Sharma, Gaurav, Chandra, Kailash & Banerjee, Dhriti, 2021, Culex (Culex) gaugleri, a new species (Diptera: Culicidae) from India, Records of the Zoological Survey of India 121 (4), pp. 429-439 : 431-436

Culex (Culex) gaugleri sp. nov. Suman ( Figure 1 , 2 , 3 , 4 )

Type material: Holotype: 1 female: India, Tamil Nadu, Kodaikanal hills, 10°13’23”N 77°20’48”E, 3-iii-2019, collected D.S. Suman (21927/H6) . Paratype: 1 Female: same locality data as holotype (21928/H6).

Type locality: India, Tamil Nadu, Kodaikanal hills .

LSID: urn:lsid:zoobank.org:pub:E5656E2F-4F5A-44BB-B109-D3A11776DC69

Type depository: The type material is deposited in Diptera section, Zoological Survey of India, Kolkata ( NZSI) .

Diagnosis: This new species contains the following diagnostic features that can be used to distinguish from other species of the Mimeticus Subgroup : (1) absence of pale spot at the furcation of M vein, (2) the furcation points of vein R 2+3 and M are at the same levels, and (3) absence of anterior tibial longitudinal pale stripe on fore-, mid- and hind legs. The presence of a completely dark area at vein M furcation explicitly differentiates

Cx. gaugleri sp. nov. from the species having prominent pale spots on the furcation of vein M i.e. Cx. jacksoni Cx.

mimeticus , Culex diengensis Brug, 1931 , Cx. mimuloides ,

Devi Shankar Suman, Souvik De, Gaurav Sharma, Kailash Chandra and Dhriti Banerjee Cx. mimulus , Cx. orientalis , Culex tsengi Lien, 1968 and Cx. katezari . Besides, the occurrence of R2 pale spot in the apical wing region of Cx. gaugleri sp. nov. differs from Cx. tsengi and Culex propinquus Colless, 1955 . The furcation points at same level in vein R 2+3 and M of Cx. gaugleri sp. nov. differentiate from Cx. mimuloides . The absence of anterior tibial longitudinal pale stripe in Cx. gaugleri sp. nov. differs from Cx. mimeticus and Cx. mimuloides (pale stripe on the hind tibia) and Cx. jacksoni , Cx. tsengi and Cx. mimuloides (mid tibia). Basal pale bands on abdominal terga from segment II-VI of Cx. gaugleri sp. nov. differ from Culex fasyi Baisas, 1938 having apical pale bands on terga from segment III-VI.

Description (holotype, female): Culex gaugleri sp. nov. females were large in size and slender, brownish with a slightly golden scale appearance with pale white scaling at anterior and mid-proboscis, maxillary palps, vertex, lateral thorax, abdominal segments, legs and wings in different formations.

Head: ( Figure 2a, b ). 0.33±0.00 mm long. Vertex with numerous pale and white erect scales distinguishable from the top view. Maxillary palpus (0.34± 0.01 mm long) dark brown with white pale scaled tip. Proboscis (2.25± 0.15 mm long) round slender and with median broad pale ring (0.50±0.00 mm) located anteriorly from the centre. Antenna 1.91± 0.32 mm long, entirely dark brown in colour.

Thorax: ( Figure 2c, d ). 1.71± 0.07 mm long. Scutum integument ornamented with numerous narrow goldenbrown and white scales on a dark brown surface. Acrostichal, supraalar, prescutelar and scutellum areas with narrow white scale patches. Long setae: 8-10 postpronotal, 8 prealar knob, 4 upper mesokatepisternum, 2 lower mesokatepisternum, 12 antepronotal, 22 scutellum, 25-28 prescutellar, 10-12 acrostichal, 15-18 dorso-central and 10 upper mesepimeron. Prespiracular and lower mesepimeron setae absent. Pleuron light brown. Golden-yellowish scales similar to scutum scales present on antepronotum and postpronotum. White spatulate scale patches ornamented on upper mesokatepisternum, anterior mesepimeron, adjacent of lower mesokatepisternum, proepisternum, and upper region of procoxa, mesocoxa and metacoxa.

Wing: ( Figure 3 ). Elongated, 3.96 ± 0.13 mm long, 1.03 ± 0.07 mm wide. Veins with white-pale spots. Vein C with 1 st, 2 nd, 3 rd costal pale spots present at sectorial, subcostal and apical areas respectively. 1 st Costal pale spot at the middle of vein C along with 1 st subcostal pale spot. 1 st Costal pale spot larger than 1 st subcostal pale spot. Second costal pale spot at 0.75 of vein C parallel to 2 nd subcostal pale spot and 1 st R1 pale spot. Third costal pale spot at apex of vein C. A tiny pale spot present at 0.7 towards apical end of vein R2. Furcation of R 2+3 and M present at same level with pale spotting pattern of furcation R 2+3 only. Vein R 4+5 extensively pale spotted (basal 0.15 to apical 0.8) and similar to the length between humeral end of 2 nd costal and humeral end of 3 rd costal pale spot. Vein R, rs, M, M 1+2 and M 3+4 dark and without pale spot. Pale spot of vein Cu1 ranges from basal 0.1 to apical about 0.6 parallel to apical end of 1 st costal pale band and furcation of vein R 2+3. Vein Cu and Cu2 without pale spot. Anal vein pale spot covers between basal 0.15 to apical 0.51. A pale fringe spot located ahead of vein Cu2 end. The lengths of various veins and associated pale spot are summarized in Table 1.

Legs: ( Figure 4 ). Fore leg: 7.08 mm long covered mainly with dark brown scales. Fore femora 1.91 mm long with dark brown scales scattering pale scale distribution anteriorly, apical pale spots present. Fore tibia 2.25 mm

Devi Shankar Suman, Souvik De, Gaurav Sharma, Kailash Chandra and Dhriti Banerjee long covered with entirely dark scales with no pale stripe. Tibio-tarsus joint with pale spot. Tarsus 2.90 mm long. Tarsomere - I: 1.38 mm, II: 0.49 mm, III: 0.32 mm, IV: 0.13 mm, V: 0.13 mm long and I-IV entirely dark brown with basal pale band. Mid leg: 7.97 mm long. Femur 1.93 mm long dark brown with basal and apical pale spots. Tibia (2.41 mm long) without a longitudinal pale stripe. Tarsus (3.62 mm long) with tarsomere I-IV with basal pale band. Culex (Culex) gaugleri , a new species ( Diptera : Culicidae ) from India Tarsomere – I: 1.60 mm, II: 0.66 mm, III: 0.40 mm, IV:

0.22 mm, and V: 0.19 mm long. Hind leg: 10.34 mm long. Hind leg femur 2.36 mm long with dark anterior surface with scattered pale scales. Apical pale spots present. Hind tibia 2.38 mm long entirely dark without any longitudinal pale stripe. Tarsus 5.60 mm long. Tarsomere I with pale stripe anteriorly. Tarsomere II-IV entirely dark without pale stripe. All tarsomere with basal pale bands except tarsomere V. Tarsomere I: 2.32 mm, II: 1.22 mm, III: 0.90 mm, IV: 0.45 mm, V: 0.23 mm long.

Abdomen: ( Figure 2e ). 2.94 mm long. Abdominal terga II-VI covered with broad basal pale bands. Segment VII covered with basal and apical pale band. Segment VIII with basal pale band. Pale scales on basal pale band of segment I slightly extending forward in median triangle. Centre region of each dorsal band consisted of denser pale scales than edges.

Male and Immature stages: Unknown.

Etymology: The new species is named after Prof. Randy Gaugler of Rutgers University, NJ, USA, in recognition of his significant contributions to vector biology and management.

Comments: The Mimeticus subgroup belongs subgenus Culex of genus Culex . The Mimeticus Subgroup mosquitoes can be distinguished from other Culex mosquitoes with the presence of pale spots and band on the veins of the wing.

Distribution: Kodaikanal hills, Tamil Nadu, India.

Bionomics: All the specimens were collected as larvae from the water pools collected near the village. Nothing is known about the resting and biting behaviour of the adult females of the species.

Phylogenetic analysis Using COI and 16s rRNA Gene Sequences

For COI, 678 bp sequence was obtained and submitted to GenBank repository (accession no. MW309109). The sequence included 31.12 % A, 38.49 % T, 15.04 % G, and

15.33 % C nucleotides. The sequence of the 16s rRNA gene was 496 bp long and comprised of 36.69 % A, 38.50 % T,

15.72 % G, and 9.07 % C nucleotides (NCBI accession no MW298532).

The phylogenetic tree analysis based on COI gene sequences resulted in multiple clusters of Culex species. The members of mimeticus species complex formed an upper cluster in which Cx. gaugleri sp. nov. formed a clade with Cx. jacksoni whereas near Cx. tsengi formed a separate clade and shows a close relationship with Cx. mimeticus . Culex mimulus formed separate clades and near Cx. tianpingensis form a cluster with Cx. murrelli ( Figure 5 ). The phylogenetic tree based on 16s rRNA gene sequences of Cx. gaugleri sp. nov. showed a close relationship with Cx. mimeticus whereas Cx. vishnui showed clade with Cx. tritaeniorhynchus ( Figure 6 ).

Figures

Figure 1. Culex gaugleri sp. nov. (holotype, female) a lateral view of entire mosquito.

Figure 2. Culex gaugleri sp. nov. (holotype, female): a) proboscis and maxillary palpi, b) head, c) lateral thorax, d) scutum, and e) dorsal abdomen.

Figure 3. Culex gaugleri sp. nov. (holotype, female), wing with pale spots representation on different veins and dark spot at M-vein.

Figure 4. Culex gaugleri sp. nov. (female, holotype), legs. Anterior view. Abbreviations: FL - Fore leg, ML – Mid leg, HL – Hind leg.

Figure 5. Phylogenetic tree of Culex gaugleri sp. nov. with other mosquitoes using mitochondrial cytochrome oxidase I (COI) gene sequences constructed with maximum likelihood method (1000 boot straps).

Figure 6. Phylogenetic tree of Culex gaugleri sp. nov. with other mosquitoes using mitochondrial 16s rRNA gene sequences con- structed with maximum likelihood method (1000 boot straps).