Leptoconops (Holoconops) beccus, Ghosh & Pal & Hazra, 2025

Leptoconops (Holoconops) beccus sp. nov.

NCBI GenBank Accession no.

PP 358259.

Type material.

Holotype ♂, India • West Bengal, Purba Medinipur, Digha (21.621513 ° N, 89.874962 ° E), 30. X. 2023, Light trap, Col. L. Ghosh. GoogleMaps Paratypes • 5 ♂♂ and 3 ♀♀, same data as holotype GoogleMaps .

Diagnosis.

The only species of the subgenus Holoconops from the Oriental realm that is diagnosed by the following combination of characters: Adult male (Fig. 1 A – I View Figure 1 ). Gonocoxite wider at base to sub-basal part and narrow at anterior part; gonostylus short and stout, curved at middle and apex with two spines; parameres jointed at middle; posterior portion roughly rectangular, apex of paramere bearing an outwardly directed small projection; aedeagus elongate, rod-shaped, little swollen at apex. Adult female (Fig. 1 J – R View Figure 1 ). Eyes bare; mandible with 12–13 teeth, palpomere III with 4–5 well developed protruded capitate sensilla; two unequal spermathecae without any hyaline punctation.

Description.

Male (n = 6). Head. Head dark brown, eyes bare and separated about as wide as 10 facets. All flagellomeres (I – XII) small and globular except terminal flagellomere (XIII); proportion of length of flagellomeres (I – XIII): 18–20 (19.2): 09–10 (9.66): 08–11 (9.6): 08–11 (9.83): 08–11 (9.66): 08–10 (9.83): 07–10 (9.5): 08–11 (9.83): 08–12 (10): 10–15 (11.83): 10–15 (11.83): 11–20 (14.66): 36–45 (39.5); AR: 0.93–1.05 (0.98) (Fig. 1 A View Figure 1 ). Maxillary palp with four palpomeres (terminal two fused); palpomere III (Fig. 1 B View Figure 1 ) longest with a round, shallow sensory pit at apical end, with 4–5 protruding capitate sensilla; proportion of length of palpomeres (I – IV): 10–12 (11.3): 07–10 (8.6): 17–22 (20.5): 16–20 (18); PR 3.00–3.33 (3.1); P / H 0.62–0.64 (0.63).

Thorax. Dark brown. Scutellum with two bristles.

Wing (Fig. 1 C View Figure 1 ). Covered with numerous microtrichia. WL 0.75–0.90 (0.82), WW 0.30–0.35 (0.32), CR 0.40–0.47 (0.45); stigma pale brown.

Legs. Uniformly brown to dark brown, without any banding pattern (Fig. 1 D View Figure 1 ). HTC (Fig. 1 E View Figure 1 ) with four spines and a spur; first one smallest, near spur and second one longest; first to fourth ones starting from spur measuring 20–25 (22.5), 42.5–45 (44.2), 30–37 (34), 25–32.5 (29.2) respectively. TRI 1.50–1.62 (1.56), TRII 1.38–1.51 (1.47), TRIII 1.25–1.40 (1.34).

Abdomen. Dark Brown without any scale. Sternite IX 70–82 (75) long and 107–112 (109.6) wide, 1.4 times wider than length. Tergite IX 130–150 (140.5) long, 110–122 (117) wide, almost 1.2 times longer than wide and posterior margin triangular extending up to apex of Gonocoxite; basal margin of tergite IX bearing a outwardly directed, crescent-shaped greatly sclerotised structure with a sharply pointed inwardly directed spine at middle.

Genitalia (Figs 1 F – I View Figure 1 ). Apicolateral process small with 8–10 setae. Gonocoxite dark brown (Fig. 1 F View Figure 1 ); wider at base and narrower in apex, 112–127 (119) long, almost twice its greatest breadth, 62–67 (63) with stout setae on inner part of gonocoxite. Gonostylus brown (Fig. 1 G View Figure 1 ), 40–52 (46.5) long and 15–20 (18.33) wide, usually 0.4 times gonocoxal length, apex of gonostylus with two well-sclerotised equal-sized spines. Parameres (Fig. 1 I View Figure 1 ) jointed at middle, basal part of each paramere roughly trapezoid in shape, apex of paramere with outwardly directed small projection, distal part each paramere boot-shaped. Aedeagus elongated, rod-shaped, little blunt at apex (Fig. 1 H View Figure 1 ).

Female (n = 3). Overall, they have similar body colouration, and distribution of setae on body (Fig. 1 J View Figure 1 ); similar shape of maxillary palp with males, hind tibial comb but some usual sexual and other differences are stated below.

Head. All antennal flagellomeres rounded except terminal one (elongated) (Fig. 1 K View Figure 1 ), pale brown to brown, bearing sensilla chaetica (I – X); terminal flagellomere (XI) with sensilla trichodea; proportion of length of flagellomeres (I – XI): 7–10 (8.33): 7–8 (7.33): 5–8 (6.33): 7–8 (7.33): 7–8 (7.33): 8–10 (8.66): 7–8 (7.33): 6–7 (6.66): 7–10 (8): 7–10 (8): 19–25 (21.33); AR 0.62–0.67 (0.64). Mandible armed, with 12–13 mandibular teeth (Fig. 1 L View Figure 1 ). Labrum with five serrations. Clypeus with four setae arranged in a row (Fig. 1 M View Figure 1 ). Proportion of length of palpomeres (Fig. 1 N View Figure 1 ) (I – III, IV + V): 8–10 (9): 8–10 (9): 16–25 (21): 10–19 (14.66); PR 1.7–2.1 (1.9) and P / H 0.80–0.88 (0.83).

Thorax. Scutum and scutellum dark brown; scutellum with four bristles.

Wings (Fig. 1 O View Figure 1 ). WL 0.77–0.90 (0.84), WW 0.36–0.42 (0.38) and CR 0.44–0.49 (0.46).

Legs. TRI 1.71–1.82 (1.77), TRII 1.33–1.51 (1.41), TRIII 1.40–1.48 (1.44); HTC with four spines and a spur (Fig. 1 P View Figure 1 ); first to fourth spines from spur measuring 20–22.5 (21), 37.5–42.5 (39), 35–38 (36.5), 24–26 (25), respectively.

Abdomen (Figs 1 Q – R View Figure 1 ). Dark brown without any scales, with setae sparsely distributed. Genital lamellae pale brown (Fig. 1 Q View Figure 1 ); little shorter, flat at base, and gradually narrow in apical part, 1.5 times longer than wide and roughly 2.5 times longer than sternite IX; sternite IX 55–63 (60) long and 162–175 (168) wide, well excavated. Spermathecae (Fig. 1 R View Figure 1 ) two, oval, almost equal, well sclerotised, without any short neck and hyaline punctation; measuring about 40–47 (44.3) × 25–30 (27.3) and 36–44 (40.3) × 25–32 (28.3).

Remarks.

The Indian species Leptoconops brevistylus Mazumdar, Saha & Chaudhuri, 2010 differs from L. beccus sp. nov. in separate parameres, nearly U-shaped aedeagus with basal ends tapered in male, and double rows of clypeal setae, HTC with three spines, and two unequal, oval to sub-oval spermathecae in female. Another Indian species L. fortipalpus Mazumdar, Saha & Chaudhuri, 2010 can be distinguished from the new species by double rows of clypeal setae, palpomeres I and II somewhat fused, lower PR (1.62) and unequal, oval spermathecae in female. Female members of L. tenebrostigmatus Mazumdar, Saha & Chaudhuri, 2010 can be separated from the new species in higher antennal ratio (> 1), eyes separated by six facets, double rows of clypeal setae, palpomeres I and II not well separated, and higher PR (2.4).

The males of Nepalese species L. amplifemoralis Chanthawanich & Delfinado, 1967 differ in having the roughly rhomboid aedeagus, apex of parameres with a recurved spine and the absence of spines on the tergite band. The Chinese species L. menglaensis Liu & Yu, 1998 can be segregated from the new species in separate parameres, elongated gonocoxite and club-shaped aedeagus. The Thai species L. xuthosceles Chanthawanich & Delfinado, 1967 differs in swollen parameres in the middle and pointed recurved spine-like structure. The Chinese species L. yunhsienensis Yu, 1963 can be differentiated by separate parameres and hairy eyes. The females of L. amplifemoralis differ in round, equal spermathecae, and much longer and wider wing. Females L. yunhsienensis can be separated by hairy eyes and hyaline punctation in spermathecae. Females of L. menglaensis can be segregated from the new species by peach-shaped spermathecae.

At present, only three species of the genus Leptoconops have publicly available COI sequences. Two of these species are categorized in the subgenus Leptoconops , while the other falls under the subgenus Styloconops . Our proposed new species falls in the subgenus Holoconops . So at present, a molecular phylogenetic analysis may not yield fruitful results in the current scenario.

Etymology.

The specific name of the new species “ beccus ” derives from the beak-like projection of the apex of parameres.

Distribution.

India (West Bengal).

Bionomics.

Leptoconops (Holoconops) beccus sp. nov. was procured from the Digha (6 m MSL), coastal plain of Purba Medinipur district, near the Bay of Bengal while the other three species [ L. (H.) brevistylus ; L. (H.) fortipalpus and L. (H.) tenebrostigmatus ] were recorded mainly from the hilly area of the Chota Nagpur Plateau near the Mithon Water Reservoir (50 m MSL), Jharkhand, and Burdwan Town (30 m MSL), a mature delta of the Deltaic Proper of Gangetic West Bengal. The Nepalese species L. (H.) amplifemoralis Chanthawanich & Delfinado, 1967 was reported from Kathmandu (1300 m MSL), a part of Himalaya Biodiversity Hotspot. The Thai species L. (H.) xuthosceles was described from Chiang Mai (310 m MSL) near the Mae Ping River by Chanthawanich and Delfinado 1967. The biting midge L. (H.) ascius Yu and Hui , in Yu 1988 was described near the Lancang River (580 m MSL), Jinghong, Yunnan Province of the Oriental China. Both Oriental Chinese species, L. (H.) menglaensis Lee, 1978 and L. (H.) yunnanensis Liu & Yu, 1998 were reported from Mengla (600 m asl) of Yunnan Province. Another Chinese species L. (H.) yunhsienensis was described from Yunxian County (2000 m MSL) of Yunnan Province by Yu (1963). It was Clastier (1974) who described L. (H.) laosensis from the Nam Khan located on the left bank of the River Mekong (1800 m MSL), Laos. The new species in the subgenus Holoconops is only reported from the coastal area of the Oriental region.