STICTOCOCCIDAE Lindinger 1913

Hodgson, Chris, 2020, A review of neococcid scale insects (Hemiptera: Sternorrhyncha: Coccomorpha) based on the morphology of the adult males, Zootaxa 4765 (1), pp. 1-264 : 114-115

STICTOCOCCIDAE Lindinger 1913

Stictococcus Cockerell 1903, 64 . Type species: Stictococcus sjostedti Cockerell. Type designation unknown.

Introduction. The family Stictococcidae contains 3 genera: Hockiana Richard (1976) with 2 species, Parastictococcus Richard (1976) with 8 species, and Stictococcus Cockerell with 8 species. The family is restricted to Africa and some species are pests, particularly of cocoa and cassava. Two species ( S. vayssierei and S. subterraneus ) are subterranean and feed on the roots of cassava, the remainder are non-gall inducing species found on almost any part of the rest of the plant. All species are apparently attended by ants ( Williams et al. 2010). No detailed descriptions of male Stictococcidae have been published although Richard (1971) discussed the males and provided some small but quite detailed illustrations of three species, Stictococcus intermedius Newstead , S. vayssierei Richard and Parastictococcus gowdeyi (Newstead) . No males of Hockiana have been described.

Family diagnosis based on adult male morphology of 2 species of Parastictococcus and 3 species of Stictococcus ( Figs 47–52 ). Body not attenuated, abdomen gradually narrowing to long, needle-like penial sheath; setae frequent and long, fs often hard to distinguisable from hs; loculate pores absent apart from in glandular pouches. Head: simple pores absent; preocular ridge absent; interocular ridge absent; genal setae present; ocelli present, almost touching postocular ridge; striations or reticulations present associated with mid-cranial ridge; postoccipital ridge well developed (absent on P. multispinosus and P. brachystegiae ); antennae short, 6 or 7 segmented; flagellar segments with both hs and fs; capitate setae retricted to 3 on each apical segment. Thorax: prosternal median ridge poorly developed or absent; prosternal setae present; prescutum oval, prescutal ridge and prescutal sclerite often poorly developed, prescutum often appearing to be fused with scutum; prescutum with prescutal setae; margin between prescutum and median part of scutum marked by narrow reticulations; scutum without a median membranous area; scutal setae mainly present laterally; scutellum with a large foramen and scutellar setae; postmesospiracular setae present; basisternum without a median ridge but with many setae; lateropleurite with setae along dorso-lateral margin; mesepimeron with setae; mesepisternal setae present; metasternum with many setae; metaprecoxal ridge absent; postmetaspiracular setae present (absent on S. vaysierei); hamulohalteres absent; alar lobes absent; alar setae absent; alar sensoria absent; trochanter with sensoria in a line on each side; legs with many fs and some hs, each tibia with 2 large spurs; tibio-tarsal segmentation distinct; tarsi 1 segmented; tarsal campaniform pore present; tarsal digitules capitate but offset and dissimilar, one arising on dorsal surface and other close to claw lateroventrally; claw digitules capitate; claws narrow but with a large denticle at broad proximal end. Abdomen: tergites and sternites often showing some sclerotisation; fs common on both dorsum and venter; glandular pouches present on segment VIII, shallow, with very few loculate pores (absent on S. vaysierrei ); glandular pouch setae long; caudal extensions on segment VIII small but present; segment IX particularly large and separated from style by what appears to be an intersegmental membrane; segment IX with 2 or 3 long setae on lateroventral margin; with 2 pairs of long hs; anus large and distinct, located near posterior margin of segment IX; style bulbous anteriorly, becoming needle-like; style long and narrow (at least 2–3 times as long as segment IX); aedeagus very broad anteriorly, narrow posteriorly and as long as or longer than penial sheath.

The most unique characters of this family appear to be the: (i) form of the tarsal digitules, (ii) presence of fs on the lateropleurite; (ii) presence of setae on mesepisternum; (iv) reduced number of antennal segments and (v) complete separation of abdominal segment IX from the style.

Key to the adult male Stictococcidae (based on those described below).

1. Antennae 6 segmented. With both tarsal digitules hair-like with a small capitate apex. Loculate pores absent........................................................................................... Parastictococcus spp. … 2

- Antennae 7 segmented. With one tarsal digitule about half the length of the other and much broader. Loculate pores present near posterior spiracles … Stictococcus spp.................................................................... 4

2. Style long and narrow, about 5 times longer than basal width. Most setae on antennae very long, their length 2 or more times width of antennal segments. Mesepisternal setae present.......................... P. hargreavesi (Vayssière) ( Fig. 48 )

- Style short and broad, only about 2–3 times longer than basal width of segment IX. Most setae on antennae short, only about as long as width of each antennal segment. Mesepisternal setae absent............................................. 3

3. With about 14 dorsal head setae on each side of mid-cranial ridge. Reticulations on scutum absent laterally................................................................................. P. multispinosus Newstead * ( Figs 49 , 50 )

- With less than 10 dorsal head setae on each side of mid-cranial ridge. Reticulations present throughout scutum..................................................................................... P. brachystegiae (Hall) * ( Fig. 47 )

4. Glandular pouches absent. Pleural setae in this position much shorter than length of abdominal segment IX......................................................................................... S. vayssierei Richardǂ ( Fig. 52 )

- Glandular pouches present. Glandular pouch setae as long as or longer than abdominal segment IX............................................................................................. S. intermedius Newstead ( Fig. 51 )

Notes: *The adult males of P. multispinosus and P. brachystegiae are very similar and the significance of these differences is unknown.

ǂ Richard (1971) considered that the adult males of P. vayssierei are apterous. However, as the mesothorax is normally developed (i.e., heavily sclerotised and apparently similar in structure to that of alate species), it is here assumed that the specimen is damaged and that this species is alate. On the other hand, P. vayssierei feeds on the roots of its host plants and the possession of wings might be a disadvantage ….!

Richard (1971, p. 582) also illustrates the adult male of P. gowdeyi . Based on these illustrations, the adult male of P gowdeyi has a style somewhat intermediate in length compared with the long style of P. hargreavesi and the short style of P. multispinosus , has quite long setae on the antennae and the abdominal tergites are all sclerotised.

Figures

FIGURE 47. Parastictococcus brachystegiae (Hall). Macropterous male. (Stictococcidae).

FIGURE 48. Parastictococcus hargreavesi (Vayssière). Macropterous male. (Stictococcidae). Where A=cranial apophysis.

FIGURE 49. Parastictococcus multispinosus (Newstead). Macropterous male. (Stictococcidae). Where D=fleshy setae and E=hairlike seta.

FIGURE 50. Parastictococcus?multispinosus (Newstead). Macropterous male. (Stictococcidae). Where A=cranial apophysis.

FIGURE 51. Stictococcus intermedius Newstead. Macropterous male. (Stictococcidae).WhereA=cranial apophysis and L=loculate pore.

FIGURE 52. Stictococcus vayssierei Richard. Macropterous male. (Stictococcidae). Where L=loculate pore. Where A=cranial apophysis, E=divided hair-like seta and L=loculate pore.