Maculolachnus blackmani Kanturski & Chakrabarti 2022, sp. nov.
Creators: name: Kanturski, Mariusz
name: Chakrabarti, Samiran
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Aphididae
Maculolachnus
Maculolachnus blackmani

description: Maculolachnus blackmani sp. nov.
Maculolachnus submacula (Walker) David et al. 1969: 158; Ghosh, 1982: 106; Nauman-Etienne & Remaudière, 1995: 39
Apterous viviparous female—description
(Figs 1–4, Table 1)
Colour. In life unknown. Pigmentation on slide: head and thorax sclerotized light brown to brown; ANT brown with basal parts of ANT III–V slightly paler; coxae brown; femora brown with paler proximal parts; tibiae brown with more or less paler middle section; tarsi brown; dorsal abdominal scleroites and SIPH sclerites brown; cauda, anal and genital plate brown (Fig. 1). Morphometric characters: Body oval or slightly egg-shaped covered by numerous setae. HW 0.43–0.46 × ANT. Head with numerous medium in length, stiff setae with expanded and blunt apices, 0.070 –0.090 mm long. ANT 0.48–0.52 × BL. ANT III with 2–9 small to medium rounded secondary rhinaria without sclerotized rims (Fig. 2a, d), ANT IV shorter than ANT V with 2 small secondary rhinaria.ANT V as long as or slightly shorter than ANT VI with big, rounded and protuberant primary rhinarium without sclerotized rim (Fig. 2b). PT 0.28–0.44 × BASE. Other antennal ratios: VI: III 0.49–0.60, V: III 0.41–0.55, IV: III 0.38–0.51, IV/V 0.89– 0.92. ANT bearing numerous, mostly medium in length, thick, rigid setae with blunt and expanded apices (Fig. 2e). ANT III setae 0.040 –0.075 mm long, LS ANT III 1.62–2.20 × BD III. ANT VI with 20–24 basal, 3 apical and 4–5 subapical setae (Fig. 2b). Rostrum reaching ABD IV. URS 0.36–0.48 × ANT III, 0.73– 0.81 × ANT VI, 2.62–3.66 × PT, 0.95–1.16 × BASE and 0.64–0.70 × HT II, with 10–12 accessory setae (Fig. 2c). III FEMORA with medium in length, thick, rigid setae with blunt and expanded apices, 0.060 –0.070 mm long. III TIBIAE have medium in length to long, thick, rigid setae with expanded and blunt apices, 0.050 –0.110 mm long. HT I with 12–14 ventral setae, HT I basal length 1.25–1.42 × dorsal length, HT I dorsal length 0.46–0.50 × HT I intersegmental length, HT I basal length 0.60–0.68 × HT I intersegmental length and HT I basal 0.37–0.47 × HT I ventral length. HT 0.56–0.73 × ANT III, 1.13–1.23 × ANT VI and 1.47–1.77 × BASE. Abdomen membranous with wrinkled cuticle and with small mostly irregular and narrow-oval scleroites (Figs 3a–c, 4a). Setae arising from scleroites are medium in length, stiff with mostly expanded and slightly flabellate or blunt apices (Fig. 3b, c). Setae with blunt apices do not arise from scleroites. Setae are 0.060 –0.095 mm long on ABD TERG I–V and 0.060 –0.100 mm long on ABD TERG VI–VIII. SIPH low, lying on setose sclerites with irregular edges (Fig. 4b). ABD VIII in form of narrow stripe on the whole segment width broken in the spinal area, with 36–40 setae (Fig. 4c). Genital plate more or less bilobed with numerous setae (Fig. 4d).
Diagnosis: The new species can be easily recognized from all other Maculolachnus species by antennae, dorsal side of body and legs with thick and stiff setae with blunt and expanded apices. From M. rubi it also differs by antennae without accessory rhinaria on ANT V and VI and from M. sijpkensi it differs additionally by dorsal side of abdomen with scleroites at setal bases. Due to the last character M. blackmani is similar to the most common M. submacula but can be distinguished by following additional characters:
• HT I with 12–14 ventral setae (20–24 in M. submacula),
• ANT VI with 20–24 basal setae (28–33 in M. submacula),
• Longest setae on III femora 0.06–0.07 mm long (0.10–0.14 in M. submacula),
• Longest setae on ABD VI–VIII 0.060 –0.100 mm long (0.13–0.14 mm long in M. submacula),
• Different ratios of antennal segments: VI/III 0.50–0.60, IV/V 0.89–0.92 and URS/HT II 0.64–0.70 (0.41– 048, 0.81–0.85 and 0.54–0.58 in M. submacula respectively)
• Different ratio of HT I basal/HT I dorsal length 1.25–1.42 (0.64–0.71 in M. submacula) and HT I dorsal/HT I intersegmental 0.46–0.50 (0.87–1.00 in M. submacula)
Etymology: We are pleased in naming the new species to honour our late friend and colleague Roger Laurence Blackman—an outstanding aphidologist and for many years specialist in the Natural History Museum in London.
Biology and distribution: The new species feeds on Rosa sp. in mountainous areas of North-Western India and North-Eastern Pakistan where it is most probably attended by ants. Apterae and nymphs were also collected infesting roots of Geranium nepalense and Geranium sp. in Garhwal Himalaya (India) but not attended by ants. On Geranium sp. (roots) this species was collected along with Protrama longitarsus sclerodensis Kumar, 1973.
Material examined: HOLOTYPE. Apterous viviparous female, INDIA, Himachal Pradesh, Kufri (2510 m) (Shimla), 10.XI.1968, on Rosa sp., (“wild rose” on the slide), K. Narayanan & David leg., BM-1984-340, NHM PARATYPES. Apterous viviparous female, PAKISTAN, Gilgit-Baltistan, Naltar (2600 m), 09.IX.1988, on Rosa sp., Nauman-Etienne leg., MNHN(EH) 23042, MNHN; apterous viviparous female, MNHN(EH) 23043, DZUS, collection data as for the previous paratype; apterous viviparous female, INDIA, Uttarakhand, Ghangaria (3049 m), 23.VII.1983, on Geranium sp. roots, S. Chakrabarti leg., 2911 (VCK); three apterous viviparous females and three nymphs, Joshimath (1875 m), 27.X.1981, on Geranium nepalense, S. Chakrabarti leg., 1486 (VCK).
Remarks: Ghosh (1982) provided a redescription based on 3 apterous viviparous females received from Dr. S. K. David, India collected on Rosa moschata in Shimla, (Himachal Pradesh, India) on 26.XI.1969 by K. Narayanan & S.G. Rajasingh as Maculolachnus submacula (coll no. 1160) which we could not examine but seem to be this new species.
Taxonomic comments
Of the four described species in the genus Maculolachnus, apterous viviparous females are known from all except M. paiki from Korea. In a general view, the specimens collected from India and Pakistan indeed could be misidentified with M. submacula which is of course the most common species, characterized by numerous scattered scleroites on the dorsal side of abdomen. After examination of the chaetotaxy under higher magnification, significant differences in the characters of the setae and cuticle can be noted. First of all, M. blackmani has thicker setae (especially on the apical area) which are additionally stiff and with expanded and slightly flabellate apices. They are arising from sclerites which in comparison with M. submacula are smaller, more rounded and with gentle edges. The abdominal cuticle is also evidently wrinkled (Fig. 3a–c). In M. submacula the sclerites are larger and more scattered with evidently finer, hair-like setae which in the apical area are very fine and always pointed (Fig. 3d–f). Very similar setae can be found in M. sijpkensi, and the dorsal abdomen is moreover characterized by smooth cuticle without scleroites (Fig. 3g –i). Long setae arising from scleroites make M. blackmani similar to M. rubi which is known from Meghalaya in India (Ghosh1982). However, this unusual not rose-feeding species, represents completely different features which do not fit to characters of the remaining Maculolachnus, like: presence of secondary rhinaria on all flagellar segments (even on ANT VI which is rather a character of males than apterous females), pointed URS, accessory rhinaria fused together by the major rhinarium and more than one peg-like setae on HT I put into question the generic identity of this species which will be undoubtedly solved in future taxonomical studies on this and similar genera. Maculolachnus blackmani seems not only feed on Rosa spp. as it has been collected also from roots of Geranium nepalense and Geranium sp. This is not an exception as the M. submacula has been recorded similarly on the roots of Geranium collinum, G. sibiricum and Potentilla anserina (Kadyrbekov, 2012). The new species can due to its occurrence in high montane areas be an endemic element for Himalaya like e.g. Pseudessigella Hille Ris Lambers of Eulachnini, only restricted to Jammu & Kashmir in Northern India and North-Eastern Pakistan (Kanturski et al. 2017).
description: Published as part of Kanturski, Mariusz & Chakrabarti, Samiran, 2022, Maculolachnus blackmani (Hemiptera: Aphididae: Lachninae) - a new aphid species from India and Pakistan with key to species of the genus, pp. 361-368 in Zootaxa 5183 (1) on pages 362-365, DOI: 10.11646/zootaxa.5183.1.26, http://zenodo.org/record/7070274