Valid Names Results

Lachnodius Maskell, 1896 (Eriococcidae)

Nomenclatural History

• Lachnodius Maskell 1896b: 400. Type species: Dactylopius eucalypti Maskell by subsequent designation Fernal1903 . accepted valid name
• Pseudopsylla Froggatt 1921b: 6. Type species: Pseudopsylla hirsutus Froggatt by monotypy and original designation . junior synonym (discovered by Beards1982a: 31)

Remarks

• Systematics: The phylogenetic relationships of Lachnodius have been an enigma. Cook et al. (2002) found support for a monophyletic group comprised of an unidentified Lachnodius species, Tanyscelis mammularis (Froggatt) and Ascelis praemollis Schrader (both of the latter being members of Eriococcidae in its current form); all three species induce galls on myrtaceous hosts. Cook and Gullan (2004) found these same three taxa inide a cladse of Myrtaceae-feeding species that formed part of a larger clade of species from the Southern Hemisphere. The most likely resolution will entail the recognition of the Myrtaceae-feeding (MF) clade of Cook and Gullan (2004) as a formal family-level taxon. (Hardy, et al., 2019) Generic characteristics that distinguish this genus from all other eriococcids are: without protruding anal lobes; head with pair of lobular protuberances; anal ring pores situated at base of anal ring setae; dorsal margin with finge of enlarged setae (Beardsley, 1982a).
• Structure: Female insects active or stationary, naked or covered with cottony or mealy or waxy secretion (Maskell, 1896b). Body outline circular to oval. In most species eyes on margin (on venter in L. froggatti, and absent in L. sealakeensis). Antennae six to seven-segmented. Pair of broad, blister-like frontal lobes between antennae; a series of elongate setae along posterior margin of lobes. (Hardy, et al., 2019) It appears that parasitization affects the development of structures in the host’s integument, in particular the macrotubular ducts, making identification of parasitized specimens potentially problematic. Compared to unparasitized individuals, parasitized female specimens identified as L. lectularius often have fewer or smaller macrotubular ducts. Normally, the dorsal macrotubular ducts are numerous and large (ca. 6–8 μm rim diameter). In some parasitized specimens the ducts are few, whereas in others they are abundant but small (ca. 2–3 μm in diameter and without well-defined rims). (Hardy, et al., 2019)
• Biology: The females of all species of Lachnodius induce galls of varying complexity on the leaves, buds, stems, or main trunk of species of Eucalyptus or Corymbia (Myrtaceae). Galls consist of a pit in swollen plant tissue with insect’s dorsum either exposed or partially concealed. Females remain in their gall after their imaginal molt, and then at maturity, depending on species, either desert their gall and move elsewhere for oviposition, or remain in their gall for reproduction. Males, in the few species for which they are known, induce galls as first-instar nymphs but then, near the end of their second instar, vacate the gall and move to another site to form cocoons in which they complete their development. (Hardy, et al., 2019)
• General Remarks: Detailed redescription and photographs in Hardy, et al., 2019. Generic diagnosis of the male in Hodgson, 2020.

Keys

• Hodgso2020: pp.19-22 ( Adult (M) ) [Neococcoid higher taxa]
• HardyGu2007: pp.108 ( Adult (F) ) [Key to the adult females of genera of felt scales on Eucalyptus and Corymbia]

Associated References

• Balach1948b: taxonomy, pp. 253
• Beards1974a: distribution, host, taxonomy, pp. 329, 330, 332, 342
• Beards1982a: description, distribution, host, illustration, taxonomy, pp. 31-35
• Beards1984: description, distribution, host, pp. 86, 91-92
• Beards1994: distribution, host, taxonomy, pp. 238
• Beards1995a: host, taxonomy, pp. 100
• Borchs1949: taxonomy, pp. 44
• Cocker1899a: distribution, taxonomy, pp. 391
• Cocker1899m: taxonomy, pp. 278
• CookGu2004: taxonomy, pp. 442
• CostaL1934: taxonomy, pp. 132
• Ferris1919a: description, distribution, taxonomy, pp. 23
• Ferris1921b: taxonomy, pp. 60
• Ferris1955: description, taxonomy, pp. 1
• Frogga1917: description, distribution, host, taxonomy, pp. 136
• Frogga1921a: description, distribution, host, taxonomy, pp. 46, 109
• Frogga1921b: description, distribution, pp. 6
• Green1922: description, taxonomy, pp. 400
• Gullan1984b: taxonomy, pp. 381
• GullanMiCo2005: ecology, host, pp. 166
• HardyBeGu2011: host, taxonomy, pp. 498
• HardyBeGu2019: biology, diagnosis, illustration, key, revision, taxonomy, pp.
• HardyGu2007: host, illustration, taxonomy, pp. 106-108
• HardyGu2010: host, pp. 2
• Hodgso2020: description of male, diagnosis, key, male, taxonomy, pp. 20, 87, 89
• Hoy1963: catalog, distribution, host, pp. 165
• KondoHaCo2006: phylogeny, pp. 19
• Koteja1974: structure, taxonomy, pp. 269, 275, 308
• Koteja1974b: description, taxonomy, pp. 56
• Kozar2009: distribution, host, taxonomy, pp. 112
• Lindin1937: taxonomy, pp. 187
• MacGil1921: distribution, host, taxonomy, pp. 131, 145
• Maskel1896b: description, taxonomy, pp. 400
• MillerGi2000: catalog, taxonomy, pp. 392
• MillsMaRi2011: taxonomy, pp. 55
• MorrisMo1922: description, taxonomy, pp. 44, 47-78
• MorrisMo1966: taxonomy, pp. 102
• Nur1980: chemistry, physiology, pp. 104
• Voelck1947: distribution, host, pp. 25
• Willia1991DJ: taxonomy, pp. 461

10 Species