7-locular pore: A kind of multilocular pore with 7 divisions or loculi.


8-shaped ducts: Ducts that are shaped like an eight.

8-shaped pores: Wax producing structures that look like the number 8. Common in pit scales.


Abdomen: The posteriormost section of the three main body parts of an insect (see also head and thorax).

Abdominal segment: Division(s) of the posteriormost section of the body. See also abdomen.

Abdominal spiracle: Respiratory opening (spiracle) located on the lateral areas of 1 or more abdominal segments in the more primitive families of scale insects including the ensign scales and margarodoid groups.

Anal area: The region of the body that bears the anus; usually near the posterior end. Many important taxonomic characters are to be found in the anal area of scale insects. These characters usually correspond to adaptations that help excrete honeydew away from the relatively immobile, phloem-feeding adult female.

Anal bar: A narrow sclerotization on the ventral surface of the anal lobe of mealybugs.

Anal cerarius: The posteriormost cerarius, usually associated with the anal lobe of mealybugs and putoids (sometimes called the anal-lobe cerarius).

Anal cleft: A notch originating near the anal opening and ending at the body margin. Common in soft scales and aclerdids.

Anal fold: Apex of anal invagination when anal tube is retracted.

Anal fringe: A series of dermal projections in the anal region of lac scales.

Anal invagination: Tube containing anal ring that is everted when honeydew is excreted.

Anal lobe: Projection(s) from the body margin that are usually laterad of the anal opening. Common on felt scales.

Anal opening: The distal most portion of the excretory system; often the external source of honeydew.

Anal plate: One or two sclerotized areas that surround or cover the anal opening. Common on soft scales and aclerdids.

Anal plate protuberance: Raised area surrounding the anal plate that normally is sclerotized. Most common in the soft scale genus Ceroplastes.

Anal ring: Usually an oval sclerotized area that surrounds the anal opening; often adorned with wax pores and setae. See also anal tube sclerotization.

Anal ring pores: Wax pores embedded in the anal ring. Producing a wax tube that carries the honeydew away from the body of the scale insect.

Anal ring setae: Setae that originate on the anal ring. Usually with 6 or 8 such setae, sometimes with fewer or more.

Anal tube: A cylindrical structure that terminates at the anal opening.

Anal tube apodemes: Sclerotized bars attached to each side of the anal tube on aclerdids.

Anal tube sclerotization: Heavy pigmentation on the anal tube either as a ring on the dermal surface or as a ring internally. See also sclerotization.

Anal tubercule: A heavily sclerotized posterior prolongation of the body of lac scales.

Antenna: (pl. antennae) Pair of jointed appendages located on the head of an insect above the mouthparts. Each antenna usually consists of one or more articulated segments bearing sensory organs.In some scales, such as adult female diaspidids, the antenna is reduced to an unarticulated, unsegmented stub.

Antennal articulatory process: A projection that protrudes from the basal segment of the antenna and articulates with the second segment. Common on mealybugs.

Antennal bar: A narrow, heavily sclerotized area that extends from the base of the first antennal segment toward the distal part of the segment. See also antenna.

Antennal segments: Distinctly sclerotized section(s) of the antenna separated by membranous unsclerotized membranes. See also antenna.

Anterior: Front; or, towards the head.

Anterior cerarius: (i.e., frontal cerarius) The anteriormost cerarius on the head in mealybugs and putoids.

Anus: The posterior opening of the digestive tract.

Apical: At the end, tip, or opposite of the base (apex); i.e., the apical segment of the antenna is the segment at the tip.

Apical setae: Setae located near apex of anal plates on dorsal surface on soft scales.

Arch plate: Narrow, semicircular sclerotized area located anterior of the anal ring in lecanodiaspidids and asterolecaniids.

Areolate pattern: Oval or oblong clear areas on dorsal body surface (i.e., areolate derm pattern).

Atrium: Chamber or room-like area.

Atrium of thoracic spiracles: A chamber in the sclerotized area that surrounds the opening of the respiratory system on the thorax. See also spiracle.

Auxiliary setae: Usually long, slender setae that occur on the cerarii of mealybugs (sing. seta).


Basal: Proximal end of a structure; i.e. the base of the scale antenna is where the antenna attaches to scale body. See also antenna.

Basal claw denticle: Small projections at base of the claw of putoids. Not to be confused with the claw denticle which is near the apex of the claw.

Basal sclerotization: Heavily pigmented areas that usually are associated with the cerarii.

Bifurcate: With 2 projections, e.g., microtubulars bifurcate in Acanthococcus araucariae.

Bilocular pore: Pore with two loculi.

Brachial plate: Heavily chitinized areas perforated by pores of various types, associated with the spiracles. As a rule, the brachial plates are borne upon a process called a brachium, but in some cases they are sessile. Characteristic of lac scales.

Brachium: A more or less elongate and chitinous, or sometimes membranous process, bearing a series of brachial plates. Characteristic of lac scales.


Campaniform sensilla: Sensory pore usually located on second antennal segment and on tarsus.

Capitate setae: Setae with a swollen apex.

Carina: Ridge (pl. carinae).

Cerarian setae: Usually stout, conical seta(e) that occur on the cerarius of mealybugs and putoids.

Cerarius: (pl. cerarii) Typically an aggregation of 2 or more closely associated conical setae and a basal cluster of trilocular pores, with or without filamentous setae and discoidal pores, located near body margin. Atypically with any combination of associated conical, enlarged filamentous, or truncate setae, one or many basal trilocular or quinquelocular pores, filamentous setae, and discoidal pores. Occasionally located in medial or mediolateral areas of dorsum. In genera such as Delottococcus or Paracoccus it is difficult to make a decision about what constitutes a cerarius and is somewhat arbitrary.

Cicatrices: Minute to large pore-like structures overlying glandular cells and surrounded by a slightly sclerotized rim (Foldi 1991); they occur on the ventral and/or dorsal cuticle of females and sometimes males of many species belonging in the margarodoid families.

Circulus: Circular, oval, rectangular, or hourglass shaped areas of cuticle on the ventral side of the abdomen, present in mealybugs (Pseudococcidae), rhizoecids and putoids. The circulus functions as an adhesive organ in the mature female (Williams 1978).

Claw: Apical segment of leg, attached to tarsus. When present, always single. See also leg.

Claw denticle: Typically a single tooth on the plantar surface of the claw.

Claw digitules: Typically 2 setae originating at the base of the claw; these setae may or may not have enlarged apices.

Clubbed setae: Seta(e) with apex enlarged.

Clypeolabral shield: Basal portion of mouthparts, usually shield-shaped.

Conical seta: Enlarged seta that is cone-shaped.

Coxa: Basal segment of leg attached to trochanter.

Coxal cavity: Concave depression on coxae of hind two pairs of legs of Kilifia species.

Crenulations: Irregular raised areas usually along posterolateral margin of abdomen especially on aclerdids.

Cribriform plates: Sclerotized cuticular plates bearing numerous pores or projections that occur on the posterior dorsal portion of the abdomen of some Coccidae, Cerococcidae, and Lecanodiaspididae.

Cruciform pores: Pores with 4 loculi arranged in the form of a cross. Common on Eriococcids.

Cyst: The resting stage of some margarodoids that develops after the first instar and before the adult female. It lacks legs and has reduced antennae. 


Derm: Surface of body; skin.

Derm rugosities: Roughened areas that occur on the derm of phoenicococcids.

Dermal pocket: A series of dorsal invaginations that contain several pores and usually are arranged in longitudinal lines on certain species of stictococcids.

Digitules: Typically 2 modified setae originating at the base of the claw or on the tarsus; these setae may or may not have enlarged apices. See also claw digitules and tarsal digitules.

Dimples: Small indentations on the brachial plate of species of lac scales.

Discal setae: Setae located near center of anal plates on dorsal surface.

Discoidal pore: Simple pore(s), without obvious loculi.

Distal: The area or segment most distant from the base of a structure. For example, the distal segment on a 9-segmented antenna is segment 9.

Dorsal: Top of the structure (dorsum). For example, the dorsum of a scale insect is the top of the body.

Dorsal cerarius: Cerarii occurring on the top surface of the body.

Dorsal duct: Usually 2 large tubular ducts on dorsum anterior of anal lobes on species of Bambusaspis.

Dorsal setae: Seta(e) that occur on the dorsal surface and are not part of the cerarius.

Dorsal tube: A pair of tubelike structures found dorsally near the posterior end of the body of some adult female asterolecaniids.

Dorsomedial cerarius: Cerarii occurring along the midline of the top surface of the body.

Dorsomedial spine: (dorsal spine) Spire-shaped structure that occurs on the dorsomedial area of the abdomen on lac scales.

Duct cluster: Relatively round regions with a concentration of microducts. Characteristic of lac scales.


Enlarged setae: Setae that are not slender and filamentous. Common in eriococcids.

Eye: Generally a dome-shaped structure on the lateral margin of the head that is simple, without facets except in some adult males.


Femur: Leg segment between the trochanter and tibia. The third leg segment when all segments are present. In some families, such as Ortheziidae, the trochanter and femur are fused.

Ferrisia-like tubular duct: An oral-rim like tubular duct that has a heavily sclerotized area surrounding the duct orifice comprising sclerotizations A & B; occurring on Ferrisia species.

Filamentous duct: Thin dendritic ducts near body margin of certain species of Ceroplastes.

Filamentous seta: A slender seta.

Flower-shaped setae: Setae with apices divided into 3 or more petal-like structures located on dorsum of some species of stictococcids.

Fluted: With series of longitudinal ridges, e.g. the ovisac of Iceya purchasi.

Forelegs: The anterior pair of legs; projecting from the scale's prothorax.

Fringe setae: Ventral setae located on the anal fold anterior of the subapical setae.

Frontal cerarius: (i.e., anterior cerarius) The anteriormost cerarius on the head.


Geniculate antenna: Elbowed. Characteristic of antennae of Rhizoecidae.

Gland spines: Simple projections occurring between the pygidial lobes of armored scales; usually with 1 or more associated microducts; found in armored scales.


Head: First major portion on the body of the scale; containing the mouthparts, antennae, and eyes.

Hindlegs: The posterior pair of legs; projecting from the scale's metathorax.


Instar: The stage in an insect's life history that occurs between any two molts; e.g. the first instar is the insect that hatches from the egg, the second instar is the insect that occurs between the first and second molt.

Internal tube: Same as anal tube.

Invaginated setae: Setae that are in a pocket in the derm, i.e., sheathed.

Invaginated tubular duct: Tubular duct with a cup-like structure at the inner end.


Labial segments: 1 or up to 4 segments on the distal portion of the mouthparts.

Labium: Distal portion of the mouthparts; usually triangular shaped and the posterior section of the mouthparts on mounted specimens.

Lateral: Marginal, or on the side.

Lateral view: Looking from the side.

Leg: When present, the ambulatory structures on each side of the thoracic segments comprising the coxa, trochanter, femur, tibia, tarsus, and claw. In adult female scales, legs vary from well-developed to completely absent.

Loculus: (pl. loculi) Section(s) of various kinds of wax pores. For example, a trilocular pore has 3 sections or loculi.


Macroduct: Large-sized ducts usually on pygidium of diaspidids.

Macrotubular duct: Large-sized tubular ducts on families such as Eriococcidae.

Margin: Outside edge of a structure.

Marginal: At the margin.

Marginal duct cluster: A cluster of microducts close to the margin of the body of lac scales.

Marginal setae: Setae occurring along body margin or outside edge of body.

Marsupial band: A band of pores surrounding the external opening of the marsupium located on the ventral abdomen; occurring in some species of Steatococcus.  Homologous with the  ovisac band but usually smaller and located more centrally around the marsupium.

Marsupium: An internal pouch that holds the eggs or first instar nymphs after they are produced by some species of monophlebids; the pouch contains the vulva and cicatrices.

Median: (or medial) Middle

Metasternal sclerotization: Darkly pigmented area near hind pair of legs on ventral metathorax of conchaspidids.

Microduct: Small-sized tubular ducts on scales like diaspidids.

Microduct: Small-sized tubular ducts on scales like diaspidids.

Microtubular duct: Small-sized tubular ducts usually on eriococcids.

Midlegs: The middle pair of legs; projecting from an insect's mesothorax.

Mouthparts: The mouthparts of scale insects are composed of a clypeolabral shield, a labium, and 4 needle-like stylets. The mouthparts are found on the ventral side of the body, between the fore-coxae. They project backwards and are modified for piercing and sucking. Some adult females have reduced, or vestigial mouthparts.

Multilocular pores: Pores with more than 5 loculi. Usually abundant around the vulva.


Narrow rimmed quinquelocular pore: With thin sclerotized area around rim of pore.


Ocellar spot: 2 round or circular areas normally with radiating wrinkles on the dorsum of the head on conchaspidids.

Open center pores: Unusually large pores with central area clear and perimeter with many loculi; usually present around body margin; occurring in some species of Icerya and Steatococcus.

Operculum: Oval or round area near posterior end of body of halimococcids in second instar.

Oral collars: (oral-collar tubular ducts) Oral-collar tubular ducts are cylindrical structures that have a narrow area surrounding the orifice of the duct.

Oral rims: (oral-rim tubular ducts) Cylindrical structures that have a broad area surrounding the orifice of the duct.

Ornate setae: Multibranched or feather-shaped setae on caryonemid scales.

Ostioles: A pair of slit-like organs located between the head and prothorax and on the sixth abdominal segment (Williams 1985) of nymphs and adult females of the Phenacoleachiidae, Putoidae, most Pseudococcidae and Rhizoecidae. They discharge a fluid apparently derived from the hemolymph that solidifies on contact with air (Ferris 1950). Ostiolar secretions appear to have dual functions in defense and releasing alarm pheromones (Williams 1978).

Ovisac: A waxy secretion produced by the adult female that encloses the eggs.

Ovisac: A waxy secretion produced by the adult female that encloses the eggs.

Ovisac band: A marginal area on ortheziids and some monophlebids containing a concentration of pores and setae.  Homologous with the marsupial band in monophlebids but usually much larger, encompassing most of the ventral abdomen.


Paraphysis: (pl. paraphyses) Sclerotized processes along body margin of armored scale pygidium.

Pedicel: Membranous stalk holding dorsal spine.

Perivaginal pore clusters: Groups of pores surrounding the vulvar area on certain lac scales.

Polygonal pores: Series of variably sided pores inside anal tube of some monophlebids.

Pores: Dermal openings of secretory organs. The distribution, abundance, and morphology of these structures are frequently diagnostic.

Posterior: Toward the rear of the body, toward the anus.

Predominant pore type: Most abundant kind of pore.

Preopercular pores: Discoidal pores normally located in a cluster anterior of anal plates in soft scales.

Prevulvar setae: Ventral setae located just anterior of anal area and conspicously larger than other setae in area occurring in species of soft scales.

Pseudospines: A series of conical projections on the brachial plate of species of lac scales.

Pygidial lobes: Typically, sclerotized protrusions from the body margin of posterior abdominal segments arranged segmentally. Typical of armored scales.

Pygidial plates: Fringed projections occurring between the pygidial lobes of armored scales.

Pygidium: Posterior portion of the abdomen which has the segments coalesced into a sclerotized structure that acts like a trowel for forming the wax cover of armored scales.


Quadrilocular pores: Pores with 4 loculi.

Quinquelocular pores: Pores with 5 loculi. Common on eriococcids, soft scales, and some groups of mealybugs, to name a few groups with quinquelocular pores.


Reticulate pattern: Area of markings that contains numerous enclosed areas forming a distinct dermal pattern.

Reticulate pattern of antenna: Cross-hatched lines on at least some antennal segments. Present on some margarodoid groups. See also antenna.


Sclerotization: Hardened area that stains more darkly in slide-mounted specimens.

Sclerotization A: Inner portion of sclerotized rim of Ferrisia-like tubular duct that surrounds duct opening; in some species this area is conspicuous, in others it is inconspicuous.

Sclerotization B: Outer portion of sclerotized rim of Ferrisia-like tubular duct normally less sclerotized than sclerotization A; in some species this sclerotization may be weak or absent.

Sclerotized bar: Typically, a dark stained narrow area lateral of each side of the anal opening. Sometimes fused with the arch plate. Common on some asterolecaniids.

Seta: Sensory sclerotized structure that projects from the derm and has a basal socket. Setal shape and size can be quite diverse. See also conical seta and filamentous seta.

Setal base: The base of the seta. See also base (basal).

Simple pore: Another name for discoidal pore.

Spiracle: Sclerotized area surrounding the opening of the respiratory system or tracheae. Spiracles are present on the thorax and, in some cases, the abdomen.

Spiracular (stigmatic) setae: Marginal setae that are differentiated from other marginal setae in their size and/or shape and are located at the lateral end of the spiracular furrow. See also spiracle.

Spiracular furrow: Narrow area connecting the spiracular opening with the body margin that appears as a tubular depression in the derm and generally contains a concentration of wax pores. See also spiracle.

Spiracular pores: Pores that are placed in the spiracular atrium or immediately surrounding the spiracle. See also spiracle

Stigmatic area: Body margin surrounding bases of stigmatic setae.

Striations: A series of thin lines on the surface of a structure.

Subapical setae: Setae located near posterior apex of anal plates on ventral surface, often associated with ventral thickening. Present on soft scales.

Subdiscal setae: Setae located anterior of apical setae on anal plates on dorsal surface, but not in center of plate. Present on soft scales.

Submarginal: Near margin of structure.

Submarginal tubercles: Tubular ducts often located in submarginal areas of many species of Coccidae, usually associated with a raised area on the derm and a conspicuous duct orifice. Also see two-ringed ducts.

Submedial: Near the middle of the structure.


Tarsal digitules: Usually 2 setae located near the distal apex of the tarsus that are differentiated from other leg setae by their size or shape; usually with an apical swelling.

Tarsus: Leg segment between the tibia and the claw. The fifth segment of the leg when all segments are present. In some families, such as Micrococcidae, the tibia and tarsus are fused.

Test: Covering of scale insect body.

Thoracic spiracles: Sclerotized areas surrounding the opening of the respiratory system or tracheae. Normally located behind the first two pairs of legs or near the junction of the pro- and mesothoracic segments and between the meso- and metathoraic segments.

Thorax: Middle portion of the body containing the legs and thoracic spiracles.

Tibia: Leg segment between the femur and tarsus. The fourth segment of the leg when all segments are present. In some families, such as Micrococcidae, the tibia and tarsus are fused.

Tibio-tarsal sclerosis: Sclerotized area between tibia and tarsus on many species of Coccidae.

Tibio-tarsal spur: Noticeable membranous protrusion between the tibia and tarsus on some species of Kilifia.

Translucent pores: Clear areas on the surface of any or all of the coxa, trochanter, femur, or tibia. Usually appearing as small clear dots in the more heavily sclerotized derm of the leg. Occurring in pseudococcids, dactylopiids and eriococcids.

Trilocular pores: Pores with 3 loculi. Common on mealybugs where they have a swirled appearance when focusing up and down with a compound microscope.

Tritubular ducts: Tubular ducts in some Rhizoecidae that possess three coalesced partitions.

Trochanter: Leg segment located between the coxa and femur. Second leg segment when all segments are present. In some families, such as Ortheziidae, the trochanter and the femur are fused.

Trochanter pores: Sensory pores on each side of the trochanter, usually 2, sometimes more.

Truncate setae: Setae that look abbreviated, with the tip cut off. Common in cochineal scales.

Tubular ducts: Cylindrical structures that are the vestibules of 1 or more wax-producing glands.

Two-ringed duct: Large tubular duct that often contains two concentric rings located near the dorsal body margin on the coccidae. Especially predominant on Philephedra.


Venter: Bottom of the body.

Ventral: Bottom of the structure. For example, the venter of a scale insect is the bottom of the body.

Ventral duct group: 1 or 2 clusters of ducts anterior of mouthparts on Paratachardina species.

Ventral groove: Sclerotized indentation anterolateral of the anal plate on aclerdids.

Ventral thickening: A sclerotized bar laterad of the anal fold and fringe setae in soft scales.

Vulva: Female genital opening usually located ventrally between the 7th and 8th abdominal segments. See also abdomen.

Vulvar orientation: Arrangement of the long axis of the opening of the vulva. Usually horizontal.


Wax plates: Aggregations of spines on ortheziids that form ornate wax structures.

Wide rimmed quinquelocular pore: With broad sclerotized area around rim of pore. Present on cochineal insects.