Lachnodius maculosus Beardsley, Gullan & Hardy

Hardy, Nate B., Beardsley Jr, John W. & Gullan, Penny J., 2019, A revision of Lachnodius Maskell (Hemiptera, Coccomorpha, Eriococcidae), ZooKeys 818, pp. 43-88 : 43

Lachnodius maculosus Beardsley, Gullan & Hardy sp. n. Fig. 8

Diagnosis.

Dorsum with numerous sclerotic invaginations; marginal fringe of conical setae; some dorsal macrotubular ducts with seta touching rim; anal ring invaginated.

Description.

Adult female (n = 3). Body outline circular; length 3.45-4.84 mm (4.36 mm for holotype), greatest width 3.30-3.94 mm (3.94 mm for holotype). Eyes dorsal, very weakly developed, ca. 35 μm wide. Antennae seven-segmented; length 680-690 μm; with two hair-like setae on segment I, ca. three hair-like setae on segment II, two or three hair-like setae on segment III, three hair-like seta on segment IV, one fleshy seta on segment V, two hair-like setae + one fleshy seta on segment VI and six hair-like setae + three fleshy setae on segment V. Tentorial box with anterior extension of the dorsal arms, 285-335 μm long, 245-265 μm wide. Labium 125 μm long, 190-195 μm wide. Spiracles 130-155 μm long, 65-85 μm wide across atrium. Legs increasing in size caudad; fore legs: trochanter + femur 500 μm, tibia 425-460, tarsus 170-210 μm; mid legs: trochanter + femur 510-520 μm, tibia 445-480 μm, tarsus 170-210 μm; hind legs: trochanter + femur 555-560 μm, tibia 495-520 µm, tarsus 200-218 μm; claw 50-56 μm; fore coxa with 6 setae, mid and hind coxae each with 5 setae, trochanter with 5-7 setae, femur with 12-19 setae, tibia with 20-27 setae, tarsus with 6-15 setae; tarsal digitules 68-74 μm long, claw digitules 43-50 μm long; translucent pores on all segments of hind leg, ca. 60 pores on dorsal surface and ca. 30 pores on ventral surface. Anal ring invaginated, cuticle surrounding ring sclerotic, 68-78 μm wide, with 10-12 setae; ring setae 60-140 μm long. Pair of elongate caudal setae ca. 45 μm long.

Dorsum. Derm beset with sclerotic spicules (i.e., well-developed microtrichia), in addition to sclerotic varioles 8-12 μm wide. Dorsal setae lanceolate, 5-8 μm long, scattered over dorsum. Macrotubular ducts of two size-classes: (i) larger ducts ca. 20 μm long, with rim of dermal orifice ca. 10 μm wide; (ii) smaller ducts ca. 10 μm long, with rim of dermal orifice ca. 7 μm in diameter; many of larger ducts with one seta affixed to rim of dermal orifice. Microtubular ducts each ca. 7 μm long, with rim of dermal orifice ca. 2 μm wide, scattered over dorsum. Dorsum delimited by fringe of ca. 275 setae on each side of body; each seta with acute apex, length of setae 18-33 μm; marginal fringe interrupted between thorax and abdomen.

Venter. Ventral setae 22-60 μm long; elongate setae medial of each coxa decreasing in size caudad: ca. 100 μm long near fore coxa, ca. 55 μm long near hind coxa; longest setae on head 120-140 μm long. Macrotubular ducts of two types: (i) larger ducts with shaft subtending vestibule constricted, each ca. 22 μm long, with rim of dermal orifice ca. 6 μm wide, found along posterior margin and in transverse band across abdominal segment IV; (ii) smaller ducts with uniform shaft diameter ca. 15 μm long, with rim of dermal orifice ca. 4 μm wide, along margin anterior of larger ducts, in transverse rows across abdominal segments, amongst clusters of setae medial of each coxa. Quinquelocular pores of two distinct size-classes: (i) larger pores 5-6 μm in diameter, found on posterior abdominal segments; and (ii) smaller pores 3-4 μm in diameter, near spiracles and along margin.

Etymology.

The species name is taken from the Latin noun macula meaning spot, referring to the shallow, sclerotic pits on the dorsal body surface, combined with the Latin suffix -osus to give the meaning abundance of spots or spotted. The species epithet is a Latin masculine adjective.

Notes.

Adult females of L. maculosus are most similar those of L. melliodorae and L. parathrix . See notes under L. melliodorae for a comparison. Adult females of L. maculosus can be distinguished by having (i) two size classes of macrotubular duct on both the dorsal and ventral body surfaces ( L. melliodorae and L. parathrix have only one size class per body surface); and (ii) numerous minute sclerotic invaginations on the dorsum, each with interior margin sinusoidal ( L. parathrix without minute sclerotic invaginations, L. melliodorae with minute sclerotic invaginations urn-shaped, interior margin convex).

HMB’s Specimen Index card for collection 161/54 notes that the adult females were laying eggs in large numbers under the bark.

Material examined.

Holotype: South Australia: adult female, on slide: under bark of Eucalyptus sp., National Park, Belair, 5 Dec 1954, DC Swan, HMB Specimen Index No. 161/54 (ANIC). Paratypes: South Australia: two adult females, same data as holotype (ANIC).