Fistulococcus, Hodgson, Chris J. & Martin, And Jon H., 2005

Hodgson, Chris J. & Martin, And Jon H., 2005, Fistulococcus, a new genus of soft scale insect (Sternorrhyncha, Coccidae) proposed for two new species from Hong Kong and Papua New Guinea, Zootaxa 1075, pp. 1-40 : 2-6

FISTULOCOCCUS gen. nov.

Type species Fistulococcus pokfulamensis sp. nov.

Caution. The structure of the submarginal chambered ducts and the dorsal concave pores, discussed in the descriptions below, is difficult to ascertain. In particular, the appearance of what is here referred to as the dorsal concave pore appears to be highly variable but is thought to have the following structure: a round concavity about 4–5 m wide, whose borders may become sclerotised in older specimens; each concavity with at least one (rarely with two) heavily sclerotised bar across one end, here interpreted as the side view of an actual pore; in F. pokfulamensis ( Figs 1–3 , 5 ), there may be two types of inner ductule, either a long thin ductule or a thicker inner duct (both shown in Fig. 2 D). The concave pores of F. intsiae ( Figs 8–10 , 12 ) all appear to be identical to each other, each with a narrow ductule and a large glandular end.

Generic diagnosis: female, with four stages. ADULT FEMALE ( Figs 1 , 8 ).

Unmounted material: F. pokfulamensis ­ dorsum covered in a dusting of white wax; body surrounded by a fan of long white wax filaments, each several millimetres long, emerging from close to margin on all sides except that contiguous with plant vein. F. intsiae ­ although no residual dry material remains, a field note described the specimens as being surrounded by a patch of mealy wax on the leaf surface, and the specimens themselves appearing more similar to immature whiteflies ( Aleyrodidae ) than to scales. Mounted material (both species): elongate­oval, slightly pointed at both ends, asymmetrical, generally with one margin rather straight (through being adpressed to a major leaf vein) and other strongly curved. Stigmatic clefts distinct, broad but shallow with a narrow outer opening; margin of cleft strongly sclerotised, with or without stigmatic spines; anal cleft short. Dorsum: derm slightly to moderately sclerotised at maturity, with few or no areolations; signs of asymmetry strongly apparent in distribution of submarginal chambered ducts, these more­or­less restricted to side with curved margin (i.e., side away from leaf vein). All setae and pores absent from a narrow elongate region extending from anal plates anteriorly to head, and possibly from some areas submedially and submarginally. Dorsal setae extremely short, each with a very broad, heavily sclerotised basal socket, subequal in width to length of seta; submarginal setae in small groups of 1–4 between submarginal chambered ducts, these setae stout and more abundant than those elsewhere; other setae fine and sparsely distributed, but perhaps most abundant submedially. Dorsal pores of three types: (i) a small, round, quite heavily sclerotic microductule; (ii) a larger concave pore, generally with a sclerotised margin, with a heavily sclerotised bar across one side, here considered to be side view of actual pore, and (iii) preopercular pores widespread, in two broad bands extending anteriorly from anal plates but absent submarginally. Dorsal tubular ducts, dorsal tubercles, and pocket­like tubercles absent. Submarginal chambered ducts present, of complex structure; each with a long broad outer duct; duct opening onto dorsum complex, each duct with an inverted Ushaped group of 7–12 satellite pores around outer opening, each pore consisting of a funnel­shaped opening, this narrowing to a sclerotised pore at base, with a short inner ductule; area around satellite pores much less sclerotised, with 1–9 stout setae along outer margin, each seta similar in structure to stouter dorsal setae; chambered ducts submarginal, apparently restricted to the side of the body away from the leaf vein. Anal plates each approximately triangular, each with four strong setae ­ anterior and posterior inner marginal setae, an apical seta and an outer marginal seta. Anogenital fold with a long seta at each corner of anterior margin, and 2 or 3 on lateral margins. Anal ring with six long setae. Anal cleft margins without setae. Eyespots apparently absent. Margin: marginal setae spinose, each with rather parallel sides and pointed apex; abundant in a single line around margin; each with a strongly sclerotised and rather deep basal socket. Stigmatic clefts with inner part broad and shallow, but with a narrow outer opening; margin of cleft heavily sclerotised dorsally; stigmatic spines present or absent. Ve n te r: derm membranous, segmentation on abdomen not clear. Distribution of appendages showing distinct asymmetry, with mouthparts, legs, antennae and spiracles all closer to one margin than to other margin. Preanal disc­pores with 5–8 outer loculi, on posterior 4 abdominal segments. Spiracular disc­pores in broad bands, each pore usually with 5 outer loculi. Ventral microducts small, each with a short inner ductule. Preantennal pores present or absent. Ventral tubular ducts absent. Ventral setae infrequent; with or without anal cleft setae; with bands of setae across each abdominal segment, those medially longest; pairs of long preanal setae not always strongly differentiated. Antennae 6 segmented, with pseudo­articulations in segment III; with 3 setae on scape, 2 on pedicel and 3 on segment III; 1 fleshy seta on segment IV; 1 fleshy seta and a hair­like seta on segment V; 3 fleshy setae, 1 or 2 hair­like setae and 4 stiff setae on segment VI. Mouthparts displaced to one side but normally developed; labium twisted through 90 degrees and pointing laterally, probably with 4 pairs of setae. Spiracles normal but asymmetrically placed. Legs variable in size; tarsal campaniform pore absent; tarsal digitules longer than claw; claws either normally developed with a small denticle or very short, appearing almost bifurcate; claw digitules variable. THIRD­INSTAR FEMALE ( Figs 2 , 9 ): similar to adult female but smaller, with fewer chambered ducts and without both preopercular pores and preanal disc­pores. SECOND­INSTAR FEMALE ( Figs 3 , 10 ): similar to 3rd­instar female but significantly smaller and less asymmetrical, with fewer marginal setae and chambered ducts and without groups of dorsal setae submarginally between chambered ducts. FIRST­ INSTAR NYMPH ( Figs 4 , 11 ) (sexes probably not separable): unmounted material of F. pokfulamensis with long lateral threads of glassy wax of different structure to those of older instars (see discussion of F. pokfulamensis ). Mounted material (of both species): body barely asymmetrical; dorsal "chambered" ducts different in structure from those on later instars and more or less symmetrically distributed around submargin; concave pores absent; eyespots present; anal plates each with a very long apical seta; antennae six segmented, hair­like seta on segment 5 exceptionally long; legs well developed; claw normally developed with a denticle; claw digitules dissimilar and offset (digitules on each prothoracic tarsus even more dissimilar, one being short and setose); pair of dorsal "trilocular" pores present anteriorly on head; dorsal setae few, in a line on thorax and head.

Generic diagnosis: male, with 5 stages (pupa of neither species seen in this study). ADULT MALE (Fig. 7): of moderate size, with few hair­like setae and no fleshy setae on body; however, appendages hirsute, with numerous quite long fleshy setae, each easily differentiated from hair­like setae. Wings well­developed. Head: preocular ridge distinct and extending posteriorly to meet ventral mid­cranial ridge medially. Genae large, covered in polygonal reticulations, each without inner microridges; without genal setae. Simple eyes: two pairs, 1 pair each dorsally and ventrally; subequal in size but large and round. Postocular ridge extending medially almost to median crest dorsally and not nearly touching ocelli. Cranial apophysis well developed, long with a bifurcated apex. Antennae: 10­segmented; pedicel with a few ridges or reticulations. Prothorax: pronotal ridge well developed, probably fused medially. Post­tergite present. Mesothorax: scutum with large median membranous area; areas lateral to scutellum with polygonal reticulations; basisternum large, with a strong median ridge anteriorly, which weakens posteriorly. Metathorax: metatergal setae absent or represented by a single hair­like seta laterally; metapleural ridge fully developed; small suspensorial sclerite present; episternum poorly developed, without postmetaspiracular setae; metepimeron welldeveloped and sclerotised, without setae; dorsospiracular setae absent; metasternum unsclerotised and not reticulated; anterior metasternal and posterior metasternal setae absent. Wings: of moderate length and width; hamulohalteres present, each with a single hamulus. Legs: long and hirsute; without coxal bristles; trochanter + femur poorly separated; long trochantal seta undifferentiated; each tibia with a single apical spur; tarsal campaniform pore absent; tarsal digitules longer than claw; claws long and thin, of an unusual shape, each with a strong projection basally but without a denticle; claw digitules slightly longer than claw. Abdomen: caudal extension of segment VII small or absent, rounded and unsclerotised; setae few. Abdominal segment VIII: sternite well sclerotised; tergite with 2 ante­anal setae; caudal extension rounded; glandular pouches present, each with two setae. Genital segment: penial sheath quite stout and strong, narrowing slightly towards base and also gradually towards apex, about 1/5th total body length; basal rod apparently rather diffuse, not nearly reaching basal membranous area anteriorly; aedeagus rather broad. PREPUPA (Fig. 6): a fairly typical coccid prepupa but marginal lobes on abdominal segment VII short and rounded; lobes on segment VIII apparently absent but penial sheath broad and much longer than lobes on segment VII; spiracular disc­pores either absent or very few. SECOND­INSTAR MALE ( Figs 5 , 12 ): fairly similar to 2ndinstar females but with dorsal tubular ducts arranged in a submarginal ring, in two elongate medio­lateral lines anterior to anal plates, and in four pairs of radial lines.

Etymology. The chosen generic name derives from fistulosus (Latin, meaning full of pipes), referring to the chambered ducts around the dorsum; the suffix ­ coccus is commonly used in scale insect nomenclature.

Taxonomic affinities. Fistulococcus bears some resemblance to Ceronema Maskell (Filippiinae) , which also features chambered ducts, and all the material discussed in this paper had been provisionally placed in Ceronema in the BMNH collection by the second author. However, Fistulococcus belongs to the subfamily Coccinae (tribe Paralecaniini), as defined by Hodgson (1994), and this new genus will key out in Hodgson's (1994) key to genera of Paralecaniini with the addition of the following couplet:

1a. Submarginal chambered ducts very asymmetrically distributed, each duct with satellite pores and setae around duct orifice; ventral tubular ducts absent; stigmatic spines present or absent ....................................................... Fistulococcus Hodgson & Martin ­ Submarginal ducts generally absent but, when present, distributed a complete submarginal ring and each duct without satellite pores or setae around duct orifice; ventral tubular ducts present or absent; stigmatic spines present............................................ 1b 1b. As in couplet 1 of Hodgson’s key.

Fistulococcus contains two species, F. intsiae and F. pokfulamensis , both here described as new. However, material is at hand of a possible third species [1 pharate thirdinstar female, tree­crown sample of Anisoptera thurifera s. sp. polyandra ( Dipterocarpaceae ), Papua New Guinea, Morobe Province coast, Buso, 12.xi.1979, J.H. Martin #2843­5 (BMNH)]. Because this specimen is pharate, it is not clear which structures relate to which stage, but it appears to have well­developed legs (therefore unlikely to be F. pokfulamensis ) and to possess no stigmatic setae (therefore probably not F. intsiae ).

Figures

FIGURE 1. Fistulococcus pokfulamensis. Adult female. In this figure and in Figs. 2 to 5 inclusive, A = dorsal chambered duct; B = satellite pore to dorsal chambered duct; C = dorsal seta; D = dorsal concave pore; E = dorsal microductule; F = preopercular pore; G = dorsal tubular duct; H = dorsal view of anal plates; J = ventral view of anal area; K = marginal seta; L = spiracular discpore; M = preanal disc­pores; N = ventral microduct; P = stigmatic cleft; Q = antenna; R = metathoracic leg.

FIGURE 2. Fistulococcus pokfulamensis. Third­instar female nymph. For lettering, see Fig. 1 except S = structure of long wax filaments on all unmounted 2 nd­ and 3 rd­instar nymphs and adult females.

FIGURE 3. Fistulococcus pokfulamensis. Second­instar female nymph. For lettering, see Fig. 1 but where D = various appearances of dorsal concave pores.

FIGURE 4. Fistulococcus pokfulamensis. First­instar nymph. For lettering, see Fig. 1 except A = 1 st­instar form of dorsal chambered duct; D = dorsal " trilocular " pore, and S = structure of glassy filaments on unmounted material.

FIGURE 5. Fistulococcus pokfulamensis. Second­instar male nymph. For lettering, see Fig. 1, except S = ventral seta.

FIGURE 8. Fistulococcus intsiae. Adult female. Unless otherwise stated, in this figure and in Figs. 2 to 11 inclusive, A = dorsal chambered duct; B = satellite pore to dorsal chambered duct; C = dorsal seta; D = dorsal concave pore; E = dorsal microductule; F = preopercular pore; G = dorsal tubular duct; H = dorsal view of anal plates; J = ventral view of anal area; K = marginal seta; L = spiracular disc­pore; M = preanal disc­pores; N = ventral microduct; P = stigmatic cleft; Q = antenna; R = metathoracic leg; S = preantennal pore, and T = portion of dorsal derm.

FIGURE 9. Fistulococcus intsiae. Third­instar female nymph. For lettering, see Fig. 8, except M = ventral setae.

FIGURE 10. Fistulococcus intsiae. Second­instar female nymph. For lettering, see Fig. 8.

FIGURE 11. Fistulococcus intsiae. First­instar nymph (sex not determined). For lettering, see Fig. 8 except that A = 1 st­instar form of dorsal chambered duct, and D = dorsal " trilocular " pore.

FIGURE 12. Fistulococcus intsiae. Second­instar male nymph. For lettering see Fig 8 except M = ventral seta.