Coccus cameronensis Takahashi, 1952

Cao, Tong, Watson, Gillian W., Hodgson, Chris J., Jing, Qi & Feng, Ji-Nian, 2022, The genera Coccus and Prococcus (Hemiptera: Coccomorpha: Coccidae) in China with two new combinations and descriptions of two new species, Zootaxa 5087 (1), pp. 112-128 : 114-118

Coccus cameronensis Takahashi, 1952

( Fig. 3 )

Material examined. Type series: 2 adult females on 1 slide ( NHMUK). Lectotype (here designated) + paralectotype. Top label: Coccus / cameron- / ensis / Takah. Lower label: Coccus / acutissimus / Green, subsp. / 29.ix.1944 / Cameron / Highlands / R. Takahashi. [ Takahashi (1952) states that the specimens were collected on an undetermined tree.]

Notes: The lectotype is the specimen nearest to the small round label with “Type” on it. Both specimens have been attacked by fungus and each has a parasitoid exit hole centrally (marked X in figure). Both specimens have lost all the ventral surface except for a narrow marginal area. The line in the figure (marked Y) indicates the extent of the venter – thus all the more central structures, such as mouthparts, limbs and spiracles and other ventral dermal structures, are missing. It is thought likely that, when the parasitoids pupated within the scales, each glued the venter of the scale to the substrate; consequently, the ventral cuticle was left behind when the scales were collected.

Description of slide-mounted adult female ( Fig. 3 ): Body very elongate and narrow, slightly banana-shaped and rather pointed at each end, 6.5‒7.0 mm long and 1.6‒1.8 mm at widest point. Anal cleft 0.9 mm long. Stigmatic clefts small (compared with size of insect) but distinct. Dorsum with well-spaced areolations, these perhaps more abundant medially. Eyespots displaced onto dorsum, situated well away from margin.

Dorsum mildly sclerotised but with an elongate area of darker sclerotization medially, and on either side of anal cleft just posterior to anal plates. Dorsal setae spinose, strongly conical and sharply pointed, often with a slightly bent apex; largest (about 20‒25 um long) in a paired series of more-or-less discrete groups, with 3 groups on head (frequency taken from lectotype specimen) (anteriormost single (medial) group, I, 2 setae; paired groups: II, 0 or 1 each; more or less level with eyespots, III, 2 or 4 setae each); thorax with 3 group pairs (IV, with 5 or 7 setae each; V, with 7 or 9 each; and just anterior to posterior stigmatic cleft, VI, with 12 or 14 setae each), and abdomen with 5 group pairs (VII, each with 7 or 8 setae each; VIII, with 6 each; IX, with 6 each; X, with 5 or 6 each; and XI with 1 or 2 setae each, just anterior to anal plates). Dorsal spinose setae also present in a sparse submarginal band, these often smaller, down to about 11‒12 um long. Each areolation containing a small micropore, each about 1 um wide. Dorsum also with a slightly larger dark pore type with an inner ductule, the latter quite broad and tubular near pore, then narrowing abruptly to a fine filament with a small glandular end; fairly frequent throughout (referred to as tubular pore in Fig. 3 caption). Preopercular pores present just anterior to anal plates, each about 2.5‒3.0 um wide and probably bulbous; number uncertain but probably 4 or 5. Tubular ducts and submarginal tubercles absent. Anal plates quadrate, with anterolateral margins shorter than posterolateral margins; plate length 295‒310 um, combined widths 340 um; each plate with a setose discal seta, about 105 um long; other setae unclear but each plate perhaps with a fine apical seta. Setae along anterior and lateral margin of anal fold not visible (possibly absent).

Margin. Marginal setae of 2 sizes: (i) very large setose setae in a group anteriorly on head and on either side of anal cleft; with 4 near head apex, each 60‒120 um long, and with a single moderate-length seta situated slightly further back, each 40‒60 um long; also with 4 or 5 similar setae on either side of anal cleft, each 35‒80 um long; and (ii) rather fine setae that generally curve posteriorly, each 16‒20 um long; very sparse, distributed on each side as follows: between head apex to about level with eyespot 0, between eyespots and anterior stigmatic cleft 7 or 8; between stigmatic clefts 6‒10; on side of abdomen 12‒17 (but see under submarginal setae below). Stigmatic clefts quite small but distinct and quite deep, each with 3 fairly blunt, spinose stigmatic setae; median spines often bent, each 16‒20 um long; lateral setae small, each 8‒10 um long.

Venter. Only two ventral features could be discerned. Submarginal setae very short, each straight and about 5 um long, set very close to margin and easily mistaken for marginal setae; very sparse, with perhaps 4 on each side between stigmatic clefts. Spiracular disc pores present, occasionally visible near each stigmatic cleft, each with 5 loculi.

Comments. It is not surprising that Takahashi could not see the antennae and legs, as almost all of the venter is missing. The above description differs slightly from the brief description given by Takahashi in that there appear to be more groups of dorsal spinose setae than he mentioned.

The absence of the venter makes a discussion of the taxonomic relationships of this species difficult. Outwardly, C. cameronensis is much more similar to P. acutissimus than to C. hesperidum Linnaeus (the type species of Coccus ). However, the presence in P. cameronensis of: (i) very large marginal setae anteriorly and posteriorly, (ii) a discal seta on each anal plate, (iii) the shape and distribution of the dorsal setae, and (iv) the absence of submarginal tubercles all suggest that its relationship to P. acutissimus is not close. Prococcus cameronensis also differs in having (character-states for C. acutissimus given in brackets): (i) dorsal setae clustered into about 11 submarginal groups on each side of body (evenly distributed over dorsum); (ii) dorsal setae slender, spinose, pointed, and slightly curved distally (robust and slightly tapering with bluntly rounded apices, and straight). Despite these differences, C. cameronensis is here thought to be closer to P. acutissimus than to C. hesperidum and is here transferred to Prococcus as Prococcus cameronensis ( Takahashi, 1952) , comb. n.

Figures

FIGURE 3. Adult female of Prococcus cameronensis (Takahashi, 1952). Dorsal view of adult female, where A = marginal seta as found along lateral margins; B = ventral submarginal seta; C = large dorsal spinose seta plus setal socket found in groups on dorsum (note that the width of the socket is less than the width of an areolation (L)); D = dorsal tubular pore; E = dorsal view of anal plate; F = anogenital area; G = marginal seta as found at anterior and posterior ends; H = section of dorsum with dorsal spinose setae; J = spiracular disc pore (ventral); K = smaller dorsal spinose seta located near margins; L = areolation with dorsal microduct; M = preopercular pore; N = portion of dorsum without dorsal spinose setae; and where x = exit hole of parasitoid wasp; y = margin of existing venter, and z = ventral view of marginal area.