Ixodiphagus aethes Hayat, sp. nov.
Creators: name: Hayat, Mohammad
name: Veenakumari, Kamalanathan
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Encyrtidae
Ixodiphagus
Ixodiphagus aethes

description: 2. Ixodiphagus aethes Hayat, sp. nov.
(Figs 11–16)
Female. Holotype. Length, 0.9 mm Head dark brown. Antenna with scape brownish yellow, upper surface and lower margin brown; pedicel brownish yellow, upper surface brown; funicle yellow; clava brown. Mesosoma dark brown; metanotum and propodeum brown; tegula dark brown. Fore wing rudiment dark brown (Fig. 16). Legs with coxae black; trochanters whitish; femora and tibiae dark brown; all tarsi with segments 1–4 yellow to brownish yellow, last segment brown. Gaster black. Head, dorsum of pro- and mesothorax, and gaster densely hairy (Figs 11–14)
Head (Figs 11, 13) dorsum very slightly convex; occipital margin sharp and concave; head 2.07× as broad as median length; frontovertex broad, 0.74× head width, or head width 1.35× as broad as frontovertex width; anterior margin of frons medially concave; eye posteriorly separated from occipital margin by about diameter of two facets; ocelli very small, difficult to see in the densely punctate frontovertex, but apparently ocellar triangle with apical angle strongly obtuse; posterior ocellus nearer to eye margin than to occipital margin (ca. OOL, 1.5; OCL, 2); head, in frontal view, 1.68× as broad as high; antennal torulus with lower margin in line with lower margin of eye; torulus placed higher on head, separated from mouth margin by a distance 1.42× inter-torular distance (10:7); scrobes inverted V-shaped, with margins sharp; head, in profile, subtriangular, with eye longer than high (10:7); malar space greater than eye height (10:7); frontovertex finely reticulate, with deep, circular, setigerous punctures, separated by about their own diameters; facial region and malar space reticulate; head densely setose, setae long, largely off-white, but some pale brown, with 4 long setae along occipital margin each about twice length of other setae; eye setose, setae brown, each seta as long as a facet diameter. Antenna (Figs 12, 14, 15) [left antenna lost] with scape flattened and expanded beneath, with upper margin rounded, 1.5× as long as broad; pedicel slightly longer than F1–F3 combined; funicle segments all transverse; F1 slightly broader than F2; F2–F6 gradually increasing in width; F2 onwards with eccentric articulation, and each ventrally longer than dorsally; clava with first segment distinctly separated from second segment; third segment obliquely truncate, truncate part as long as dorsal lengths of second and third segments combined; clava as long as F2–F6 combined. Relative measurements (holotype, on card)—head dorsal width, 27; head dorsal length, 13; frontovertex width, 20; head frontal height, 16; eye height (head in profile), 7; malar space, 10; antennal scape length (width), 9 (6); pedicel length, 5; funicle length, 8; clava length, 7.
Mesosoma (Figs 11, 13) 0.71× gaster length; pronotum rectangular, 2.33× as broad as long and 1.8× as long as mesoscutum; mesoscutum 4.6× as broad as long, and slightly more than half length of scutellum; scutellum 1.6× as broad as long; propodeum very narrow in middle half; pronotum, mesoscutum and scutellum with raised reticulate sculpture and deep, circular setigerous punctures, each separated from other punctures by slightly more than its own diameter; setigerous punctures on scutellum arranged in 10 longitudinal lines; setae on pronotum and mesoscutum off-white, with a line of 4 long, pale brown setae along posterior margin of mesoscutum; scutellum with setae pale brown, arranged in 10 longitudinal lines. Fore wing rudiment a subtriangular plate (Fig. 16), reaching posteriorly to basal third of TI of gaster. Legs short and robust; coxae with several long white setae; tibiae with prominent bristle-like setae, each arising from a small tubercle. Relative measurements (holotype, on card)— mesosoma length, 25; pronotum length (width), 9 (21); mesoscutum length (width), 5 (23); scutellum length (width), 10 (16).
Metasoma (Figs 11, 12). Gaster with TI distinctly longer than following four tergites individually; tergites reticulate, with minute, setigerous punctures; setae about as follows: TI with 3 transverse lines; TII–TVI each with a single line of setae; TVII with several setae; hypopygium extending to 0.71× gaster length (Fig. 12).
Male. Unknown.
Material examined. Holotype, ♀ (on card, with left fore wing on slide, No. EH.1778; left antenna lost), labelled “ INDIA: TAMIL NADU: Dindigul, Shembaganur, 2.iv.2014 (MT), Coll. K. Veenakumari” (NBAIR, registration No. ICAR / NBAIR /EN.41)
Distribution. India: Tamil Nadu.
Etymology. Greek, aethes = unusual, curious; refers to the unusual habitus and the large, rectangular pronotum.
Comments. This new brachypterous species is not at all similar to either the brachypterous species (I. taiaroaensis) from New Zealand, or to the other macropterous species. It differs from all the species by the following combination of characters: pronotum rectangular, 1.8× as long as mesoscutum; mesoscutum transverse, 4.6× as broad as long; frontovertex with deep, circular, setigerous punctures, each separated by about its own diameter from others; pronotum, mesoscutum and scutellum with similar setigerous punctures, separated by slightly more than their own diameters, and those on scutellum arranged in 10 longitudinal lines; fore wing short, subtriangular, with apex reaching to basal third of TI of gaster; antenna with scape flattened, 1.5× as long as broad; funicle segments transverse, F2 onwards with eccentric articulation; first segment of clava distinctly separated from second segment; head, pronotum, mesonotum and gaster densely setose; tibiae of all legs with long, bristlelike setae, each arising from a small tubercle.
description: Published as part of Hayat, Mohammad & Veenakumari, Kamalanathan, 2015, Description of four new species of brachypterous Encyrtidae (Hymenoptera: Chalcidoidea) from India, pp. 259-271 in Zootaxa 3990 (2) on pages 263-265, DOI: 10.11646/zootaxa.3990.2.6, http://zenodo.org/record/240051