Marchalina, Vayssiere, 1923

Hodgson, Chris & Gounari, Sofia, 2006, Morphology of Marchalina hellenica (Gennadius) (Hemiptera: Coccoidea: Marchalinidae) from Greece, with a discussion on the identity of M. caucasica Hadzibeyli from the Caucasus, Zootaxa 1196, pp. 1-32 : 3-4

MARCHALINA Vayssière

Marchalina Vayssière, 1923: 427 .

Type species: Monophlebus hellenicus Gennadius by monotypy and original designation.

Generic diagnosis. Restricted to Pinaceae , where most stages live in cracks and crevices on the branches and/or the trunk. All stages yellow. Adult female ( Fig. 1 ; Plate 1 ): large, secreting a white, woolly ovisac during oviposition. Derm membranous; dorsum and venter covered in abundant hairs, rather fewer setae, ranging from hair­like setae with shallow basal sockets to collared setae with deep, collar­like basal sockets; with quite large loculate pores, each with a central ring of 2–9 loculi arranged like petals on a flower, and an outer ring of perhaps 12–18 (rather obscure) loculi; distribution of setae and pores rather clearly segmental on thorax and abdomen; also with some small conical pores between eyespots and scape; cicatrice absent. Antennae 11 segmented; eyespots surrounded by a strongly sclerotised area; mouthparts represented by some poorly sclerotised sclerites and a membranous labium; stylets totally wanting; legs well developed, without articulation between tibia and tarsus; prothoracic legs with particularly well­developed coxal ridges; each trochanter with a long seta on ventral surface in addition to other setae; claw with several minute denticles; claw digitules setose; thoracic spiracles relatively small; with 7 pairs of small abdominal spiracles, each with a distinct atrium; anal tube sclerotised, tubelike, without pores; possibly with a spermatheca associated with the oviduct. 3rd­instar female ( Fig. 2 ): similar to adult female but with well­developed mouthparts, many dermal spines on posterior abdominal segments and antennae with only 9 segments. 2nd­instar (probably female) ( Figs 3 & 4 ): as for 3rd­instar but with fewer dermal spines on posterior abdominal segments and only 6­segmented antennae; claw digitules without capitate apices. 1st­instar nymph ( Fig. 5 ): similar to 2nd instar in having 6­segmented antennae but body much less hirsute, with few hairs, setae and very few dermal spines; claw digitules with small capitate apices; mouthparts proportionately rather large. Prepupa ( Fig. 6 ): rather similar to 3rd­instar female in having only 9­segmented antennae but mouthparts reduced to a few sclerites and a membranous labium without stylets; also with very few dermal spines on posterior abdominal segments. Pupa (of apterous male) ( Fig. 7 ): somewhat similar to pupa but with 10­segmented antennae; very few hairs and setae; no dermal spines on abdomen; legs without claws; anal tube present; genital structures present as a more or less round sclerotised area on ventral surface of posterior abdomen. Adult male (apterous) ( Fig. 8 ; Plate 2 ): derm mainly membranous; both dorsum and venter with hairs, setae, loculate pores and a few small conical pores; loculate pores forming a denser band across dorsum of abdominal segment VI; tubular ducts restricted to a transverse group across abdominal segment VII; post­tergites present on M. hellenica (possibly absent from apterous male of M. caucasica ); antennae 10 segmented, most segments with satellite setae; compound eyes well developed; head with ( M. hellenica ) or possibly without ( M. caucasica ) a cervical groove between head and thorax; dorsally with ( M. hellenica ) or without ( M. caucasica ) a post­occipital ridge; both species with a ventral mid­cranial and pre­ocular ridges but pre­oral ridge also present on M. hellenica ; legs well developed; each trochanter with a long seta on ventral surface in addition to other setae; tibia and tarsi with bifurcated spines; tarsi 2 segmented; claws with several minute denticles; claw digitules setose; thoracic spiracles well developed; abdominal spiracles smaller, with 7 pairs; penial sheath well developed, with an elongate, eversible, spinose endophallus.

Comment. One of the main characters that diagnoses Marchalina (and therefore the Marchalinidae ) is, on the adult male, the restriction of the tubular ducts on the dorsal surface of the abdomen to abdominal segment VII only, these being replaced by numerous loculate pores on segment VI. In all other margarodoid families which have both tubular ducts and loculate pores on the abdomen, the tubular ducts are present on both segments VI and VII (i.e., Margarodidae , Xylococcidae , Kuwaniidae , Stigmacoccidae and Callipappidae) (Hodgson & Foldi, in press). The tubular ducts on male Matsucoccidae are also restricted to segment VII but males of Matsucoccus species lack loculate pores. The arrangement described here almost certainly applies also to the winged males of M. caucasica , as Hadzibeyli (1965) indicates that there are several times more pores in the anterior group (segment VI) than in the posterior group (segment VII) (ratio of pore/duct frequency 105:30), suggesting that those on segment VI are loculate pores and those on segment VII, tubular ducts.

Figures

FIGURE 1. Adult female of Marchalina hellenica. Note: 11­segmented antennae; virtual absence of mouthparts and total absence of stylets, and absence of dermal spines. On this and subsequent figures, A = small conical pore; B = loculate pore; C = minute sclerotised pore; D = tubular duct of spermatheca; E = hair; F = hair­like seta; G = collared setae; H = satellite setae; L = bifurcated seta; M = abdominal spiracle; N = anal tube; P = part of leg; Q = claw; R = view of part of dorsal derm; S = view or part of ventral derm; T = abdominal tubular duct; Z = spine on eversible endophallus. Also note that, on central drawing, density of setae only shown on one abdominal segment and leg setae only shown on methorax

PLATE 1. Adult female. Note large size, oval shape, yellow colouration and short pale antennae.

FIGURE 2. Third­instar nymph of female Marchalina hellenica. Note 9­segmented antennae, fully­developed mouthparts and presence of numerous dermal spines on posterior abdominal segments. See FIGURE 1 for labels. Also note that, on central drawing, density of body setae and loculate pores only shown on ventral abdominal segments.

PLATE 2. Adult male. Note elongate body form, yellow colouration, long dark antennae and legs, compound eyes, distinct neck region, and penial sheath with eversible endophallus.

FIGURE 3. Second­instar nymph, probably female, of Marchalina hellenica from Crete. Note 6­segmented antennae. Also fewer dermal spines on posterior abdominal segments as compared with FIGURE 4. See FIG­ URE 1 for labels.

FIGURE 4. Second­instar nymph, probably female, of Marchalina hellenica from Thessaloniki. Note 6­segmented antennae and greater frequency of dermal spines on posterior abdominal segments compared with FIG­ URE 3. See FIGURE 1 for labels.

FIGURE 5. First­instar nymph (sex undetermined) of Marchalina hellenica. Compared with 2nd­instar nymph (Figs. 3 & 4), note proportionately much larger mouthparts, many fewer setae and pores, capitate ends to claw digitules and many fewer dermal spines. See FIGURE 1 for labels.

FIGURE 6. Prepupa (3rd­instar male) of Marchalina caucasica. Note 9­segmented antennae. Also, compared with 3rd­instar female, note great reduction in mouthparts and absence of stylets, many fewer setae and pores, and many fewer dermal spines on posterior abdominal segments. See FIGURE 1 for labels.

FIGURE 7. Pupa of Marchalina hellenica. Note 10­segmented antennae; complete absence of mouthparts, claws and dermal spines; and presence of genital structures on posterior abdominal segments. See FIGURE 1 for labels.

FIGURE 8. Apterous male of Marchalina hellenica. Note shallow but distinct "neck" and large compound eyes. See Fig 1 for capital labels; other labels: ab = antennal bristle; ads = dorsal abdominal setae; as = abdominal sternite; asp = abdominal spiracle; at = abdominal tergite; avs = ventral abdominal setae; c = claw; camp = campaniform pore; cd = claw denticle; cdgt = claw digitule; ce = compound eye; cp = small conical pore; cs = collared setae; cv = cervical sclerite; cx = coxa; dhs = dorsal head setae; eph = eversible endophallus; epm 3 = metepimeron; f = femur; hs = hair; hrs = hair­like seta; lp = loculate pore; o = ocellus; ocs = ocular sclerite; pd = pedicel; plr 1 = prothoracic pleural ridge; plr 2 = mesothoracic pleural ridge; plr 3 = metathoracic pleural ridge; pls = pleural setae; pos = postoccipital sclerite; pror = preoral ridge; ps = penial sheath; psp = penial sheath pores; pss = penial sheath setae; pt = post­tergite; sc = scape; sp = minute sclerotised pore; sp 2 = mesothoracic spiracle; sp 3 = metathoracic spiracle; st 1 a = prosternal apophysis; st 2 a = mesosternal apophysis; st 3 a = metasternal apophysis; ta 1 = 1st­tarsal segment; ta 2 = 2nd­tarsal segment; tdgt = tarsal digitule; ti = tibia; tibs = tibial spurs; tr = trochanter; vhs = ventral head setae; vmcr = ventral mid­cranial ridge; vp = ventral plate; vs = ventral sclerite; and I­VIII = abdominal segments (Modified after Hodgson and Foldi, Zootaxa, in press).