''Pinnaspis'', first described by

Theodore Dru Alison Cockerell Theodore Dru Alison Cockerell (22 August 1866 – 26 January 1948) was an American entomologist and Systematics, systematic biologist who published nearly 4,000 papers, some of them only a few lines long. Cockerell's speciality was the insect or ...

in 1892, is a genus of

scale insect Scale insects are small insects of the Order (biology), order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient g ...

s belonging to the family

Diaspididae Diaspididae is the largest family of scale insects with over 2650 described species in around 400 genera. As with all scale insects, the female produces a waxy protective scale beneath which it feeds on its host plant. Diaspidid scales are far mo ...

, or armored scale insects. There are currently 42 species within the genus ''Pinnaspis''.Ben-Dov, Y
"Scales in a Family/Genus Query Results"
18 October 2012. 27 November 2012

Description

In this genus the median lobes are parallel and united by a medial zygosis.Williams, D.J. & Watson, G.W. (1988) ''The Scale Insects of the Tropical South Pacific Region. Pt. 1. Armoured Scales (Diaspididae).'' London, UK: CAB International Institute of Entomology. 290 pp. Two-barred macroducts, a bi-lobed or absent second lobe, and gland spines, rather than fringed plates between pygidial lobes, and lobed pre-pygidial abdominal segments are characteristic of ''Pinnaspis''.Ferris, G.F. & Rao, V.P. (1947) The genus "Pinnaspis" Cockerell (Homptera: Coccoidea: Diaspididae). (Contribution No. 54). ''Microentomology'' 12: 25–58.Ferris, G.F. (1937) ''Atlas of the Scale Insects of North America'' Palo Alto, California: Stanford University Press

Biology

Like all members of the family Diaspididae in ''Pinnaspis'' the females are primarily

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

, molting twice before reaching the adult stage.Koteja, J. (1990) 1.3.2. Life History. pp. 243–254. In: Rosen, D. (ed), ''Armored Scale Insects, Their Biology, Natural Enemies and Control'' eries title: World Crop Pests, Vol. 4A Amsterdam, the Netherlands: Elsevier. 386 pp. The first

instar An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...

, referred to as a crawler, due to the presence of small legs and the dispersal function of this stage. The second instar and adult female lack legs and wings, and have greatly reduced to absent antenna and eyes. A protective covering of wax is produced by the first and second instars and the adult female. The male undergoes four molts before reaching the adult stage, which is legged, winged, and has antenna and eyes. The species ''Pinnaspis buxi'' is thought to be

parthenogenic Parthenogenesis (; from the Greek + ) is a natural form of asexual reproduction in which the embryo develops directly from an egg without need for fertilization. In animals, parthenogenesis means the development of an embryo from an unfertiliz ...

, as male scales have not been found.

Distribution

The genus ''Pinnaspis'' most likely originated in Asia, with the highest diversity of species found in Asia.Ben-Dov, Y. 2012
Scalenet, "Pinnaspis"
18 October 2012 Three species, ''Pinnaspis aspidistrae'', the fern scale, ''Pinnaspis buxi'', the boxwood scale, and ''Pinnaspis strachani'', the lesser snow scale have widespread cosmopolitan distributions. These three species can be found on every continent but Antarctica.

Importance

Many species that fall within ''Pinnaspis'' are not pests, but the genus includes some serious pests. ''Pinnaspis aspidistrae'' and ''Pinnaspis strachani'' have been identified as serious pests.Miller, D.R. & Davidson, J.A. (1990) 3.1.1 "A List of the Armored Scale Insect Pests". pp. 299–306. In: Rosen, D. (ed), ''Armored Scale Insects, Their Biology, Natural Enemies and Control'' eries title: World Crop Pests, Vol. 4B Amsterdam, the Netherlands: Elsevier. 688 pp. Both ''P. aspidistrae'' and ''P. strachani'' are considered

polyphagous Feeding is the process by which organisms, typically animals, obtain food. Terminology often uses either the suffixes -vore, -vory, or -vorous from Latin ''vorare'', meaning "to devour", or -phage, -phagy, or -phagous from Greek φαγε ...

. ''P. aspidistrae'' is recorded to feed on around 60 genera, including, ''

Citrus ''Citrus'' is a genus of flowering trees and shrubs in the family Rutaceae. Plants in the genus produce citrus fruits, including important crops such as oranges, mandarins, lemons, grapefruits, pomelos, and limes. ''Citrus'' is nativ ...

'', and several types of

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

s.Miller, D.R. & Davidson, J.A. (2005) ''Armored Scale Insect Pests of Trees and Shrubs (Hemiptera: Diaspididae)''. Ithaca, New York: Comstock Publishing Associates. ''P. strachani'' is recorded to feed on over 60 genera, most commonly found on, ''

'', ''

Cocus ''Brya ebenus'', the Jamaican raintree, espino de sabana, granadillo, cocus wood, cocuswood, and coccuswood, is a species of plant in the pea family, Fabaceae. It is native to Cuba, and it has been introduced to Jamaica. Horticulturally it is kn ...

'' and ''

Hibiscus ''Hibiscus'' is a genus of flowering plants in the Malva, mallow family, Malvaceae. The genus is quite large, comprising List of Hibiscus species, several hundred species that are Native plant, native to warm temperate, Subtropics, subtropical ...

''. ''Pinnaspis buxi'' is also considered a pest, though not as serious a pest as ''P. aspidistrae'' or ''P. strachani''.

List of species

Notes on species in ''Pinnaspis''

''Pinnaspis orlandi'' (Leonardi) and ''Pinnaspis robica'' Leonardi all lack definite distinguishing characters in their descriptions. The illustration of ''Pinnaspis orlandi'' suggests that it may be ''Pinnaspis strachani''. '' Pinnaspis aspidistrae'' and '' Pinnaspis strachani'' are highly morphologically similar. These two species may possibly containing multiple cryptic species, or form one highly variable species.

References

External links

Scalenet Catalogue of ''Pinnaspis''
{{Taxonbar, from=Q7196332 Diaspididae Sternorrhyncha genera Hemiptera of Asia