Heteromargarodes hukamsinghi, Vea & Grimaldi, 2015

Vea, Isabelle M. & Grimaldi, David A., 2015, Diverse new scale insects (Hemiptera: Coccoidea) in amber from the Cretaceous and Eocene with a phylogenetic framework for fossil Coccoidea, American Museum Novitates 2015 (3823), pp. 1-80 : 26-28

Heteromargarodes hukamsinghi , new species

Figures 5A–B , 6

TYPE LOCALITY: India: Gujarat: Tadkeshwar lignite mine. Cambay Formation (Paleo-Eocene) .

TYPE: Holotype Tad-139, alate male in a piece of 10 × 5 × 1.5 mm rectangular, yellow, transparent, polished amber, with a crack, air bubbles, and soil debris; specimen is adjacent to debris, so the dorsal view is obstructed, apices of antennae are truncated, wings spread but somewhat folded; accessible view: ventral (fig. 5A–B). India: Gujarat: Tadkeshwar lignite mine, Cambay Formation (Paleo-EoceneI/7-12/2009, Grimaldi and Nascimbene, coll., deposited in Birbal Sahni Institute for Palaeobotany , Lucknow , India.

ETYMOLOGY: Patronym for Hukam Singh of the Birbal Sahni Institute for Palaeobotany, Lucknow, for his valuable work on the paleobotany of the Cambay Shale, including its amber.

DIAGNOSIS: Differs from the male of H. americanus described in Hodgson and Foldi (2006) based on the following characters: leg setae spinose (vs. hairlike), large bristles on flagellar segments absent (vs. present), penial sheath longer.

DESCRIPTION: Body large, robust, parallel sided, total length 1.6 mm, largest width 322 μm. Head: Broadly oval, 200 μm wide, 200 μm long; with elongate compound eyes, not protruding from head, almost meeting ventrally, eye length ca. 160 μm, each eye with ca. 30–40 large ommatidia. Ocelli not visible, but probably present. Dorsal ridges, if present, not observable. Ventrally with a well-developed midcranial ridge (fig. 6A), extending to and meeting compound eyes. Antenna at least 9-segmented (apical segments lost on holotype, fig. 6B); lengths of segments (in μm): scape 70–75, with less than 10 strong setose setae; pedicel 60–68, with numerous hairlike setae; flagellar segments III to IX all relatively short, narrower proximally, enlarged distally, subequal in length, 70–80 μm. All flagellar segments covered with numerous hairlike setae, each 25–30 μm long. Thorax: Head and thorax without neck constriction. Prothorax well developed but membranous, setae visible laterally (no other thoracic sclerites visible dorsally or ventrally due to debris and darkness of amber). Wings (fig. 5A): Forewings oval, of intermediate width at base, ca. 1.00 mm long and 570 μm at widest section; subcostal ridge extending from base of wing to more than 3/4 wing length, terminating at well-developed pterostigma, with a cubital ridge and anterior and posterior flexing patches; large alar fold present. Alar setae and sensoria not visible. Microtrichia absent. Hamulohalteres present but folded, number of hamuli not identifiable but probably present. Legs: Robust, cuticular reticulations absent, prolegs fossorial. Prothoracic legs (fig. 6C): coxa not visible; combined length of trochanter + femur 215 μm, 88 μm wide, with hairlike setae, bifurcated setae absent. Tibia 90 μm long, 45 μm wide, with hairlike setae becoming spinelike ventrally (tibial spurs), bifurcated setae absent; tarsus 1-segmented, 42 μm long, 35 μm wide, tarsal digitules absent; claw large 50 μm thick, claw digitules spinose, claw denticle absent. Meso- and metathoracic legs of subequal length (fig. 6D): coxa elongate, 130 μm; trochanter + femur 245 μm, 73 μm widest, with numerous hairlike setae, bifurcated setae absent; tibia 210 μm, with numerous spinelike setae and tibial spurs on ventral margin, bifurcated setae absent; tarsus 82 μm, with spinelike setae, with a longer ventral seta along tarsus; claw thin, uncurved, 55 μm, digitule spinose, extending along claw but not protruding, claw denticle absent. Abdomen: Cylindrical, ca. 660 μm long (515 μm without penial sheath), 310 μm widest, parallel sided and slightly tapered posteriorly (abdomen is partially concealed by a white coating). Abdominal setae visible on posterior segments, with groups of 4 or 5 setae (40–75 μm long) on segment VII and VIII. Dorsal structures not visible. Genital segment (fig. 6E): Penial sheath originating ventrally on tergite VII, subquadrate, tapering posteriorly, 140 μm long, 85 μm wide at base, possibly bifurcate apically. Aedeagus slender and round at apex. Eversible endophallus not visible.

Hodgsonicoccidae , new family

TYPE GENUS: Hodgsonicoccus , n. gen., by monotypy and present designation.

DIAGNOSIS: Hodgsonicoccidae differs from other families by the combination of the following characters: body exceptionally large (ca. 2 mm), head with two ocular sclerites, each bearing less than 20 large and protruding simple eyes (vs. compound eyes, rows of simple eyes or two pairs of eyes in all other Coccoidea ); antenna long, with binodose flagellar segments, each with long setae organized in whorls (similar to Monophlebidae ), each becoming shorter distally; forewings elongate and narrowed apically, subcostal ridge extending to tip of wing, cubital ridge present, membrane with microtrichia (vs. absent in other archaeococcoids with compound eyes); hamulohaltere large and broad, with microtrichia (vs. absent in all Coccoidea ), three hamuli inserted on anterior margin (vs. at the tip of hamolohaltere for all other Coccoidea ); abdomen with several long, spinose setae on posterior segments; penial sheath triangular, with a large, everted endophallus.

GENUS INCLUDED: Hodgsonicoccus , n. gen.

COMMENTS: Several features found in Hodgsonicoccidae make this new fossil family quite remarkable: (1) the eye structure was here interpreted as two ocular sclerites because they completely surround the head, as opposed to laterally located compound eyes. These sclerites, however, bear multiple rows of large simple eye facets. So far, all Recent families of coccoids bear either compound eyes or ocular sclerites with either a single row of multiple or two pairs of simple eye facets. According to the research by Koteja and Azar (2008), however, Palaeotupo danieleae Koteja and Azar, 2008 , seems to present ocular sclerites with two rows of multiple simple eye facets. This type of eye structure could possibly indicate an intermediate state between compound eyes with multiple ommatidia and one with reduction of the eyelets to two pairs, as in neococcoid families. (2) The binodose antennal segments with whorls of setae, however, are similar to archaeococcoids, such as are found in some Recent Monophlebidae genera (e.g., Drosicha ) as well as in extinct Jersicoccidae ( Koteja, 2000b) . (3) Both forewing and hamulohaltere are also peculiar: the generally elongated shape of the forewing is similar to Jersicoccidae and venation (subcostal ridge extending to tip of wing) is similar to, for instance, Recent Putoidae and extinct Labiococcidae . The hamulohaltere, although enlarged for a coccoid, is significantly reduced as compared with aphid hind wings. The position of the hamuli is particularly anteriad and is similar to that of hooked hamuli on developed hind wings of aphids, possibly suggesting a plesiomorphic state to Coccoidea . The presence of microtrichia on hamulohalteres is intriguing as in Coccoidea , when present, microtrichia are generally on the forewings (absent in archaeococcoids with compound eyes) ( Hodgson and Foldi, 2006). (4) Bifurcated setae are present in some Margarodidae , Stigmacoccidae , and Kuwaniidae , and all Monophlebidae and Coelostomidiidae ( Hodgson and Foldi, 2006) , although none of these recent families present the same combinations of characters as found in Hodgsonicoccidae . (5) Finally, the last abdominal segments present long and extremely sclerotized setae projecting posteriorly, unique to this family. Overall, the combination of the striking features listed above is unknown among Coccoidea and therefore justifies the creation of a new family.

Probably the most similar taxon to Hodgsonicoccidae is extinct Jersicoccidae , represented by Jersicoccus , described from New Jersey amber ( Koteja, 2000b). Jersicoccus has a similar elongated forewing shape and binodose antennal segments, but the eyes are definitely compound, with numerous ommatidia, and waxy filaments are present on the abdomen, suggesting the presence of tubular ducts, absent in Hodgsonicoccus . Furthermore, our phylogenetic results retrieved Hodgsonicoccus as sister group to other taxa without compound eyes, whereas Jersicoccidae was retrieved as sister family to all Coccoidea .

Figures

FIGURE 5. Photomicrographs of Heteromargarodes hukamsinghi, n. sp., holotype Tad-139. (A, B). (A) Full ventral view. (B) Enlarged ventral view of head and thorax. Hodgsonicoccus patefactus, n. sp., holotype AMNH LAE-93 (C–F). (C) Lateral side. (D) Antennae. (E) Head and thorax from lateral side. (F) Lateral side of penial sheath.

FIGURE 6. Details of Heteromargarodes hukamsinghi, n. sp. (A) Ventral view of head. (B) Antenna, (C) Fore leg. (D) Hind leg. (E) Ventral side of penial sheath.