Valid Names Results

Gigantococcus Pesson & Bielenin, 1966 (Monophlebidae)

Nomenclatural History

• Gigantococcus Pesson & Bielenin 1966: 219. Type species: Icerya maxima Newstead by monotypy and original designation . accepted valid name

Remarks

• Systematics: Pesson & Bielenin (1966) placed the genus Gigantococcus in the tribe Monophlebini, subfamily Monophlebinae. Unruh & Gullan (2008) placed this genus in the Iceryini of the Monophlebidae. Unruh & Gullan (2008b) recognised 3 species groups in the genus Gigantococcus as follows: Gigantococcus alboluteus group Three species, Gi. alboluteus, Gi. pattersoni and Gi. schoutedeni, closely resemble one another. The ventral surface of the adult females of all three species has compound multilocular pores with an 8 to 12 lobed centre and 6-8 elongate reniform outer loculi. Gigantococcus schoutedeni can be separated from the other two by the absence of large compound pores, each with a bilocular to trilocular centre and 8-12 reniform outer loculi. Gigantococcus alboluteus and Gi. pattersoni differ by the density of these compound pores: Gi. alboluteus has 3-6 of these pores in marginal clusters on the head and thorax but Gi. pattersoni has only one or two. Also, pore density in the ovisac band of Gi. alboluteus is less than that of Gi. pattersoni. Gigantococcus ewarti group Four species, Gi. euphorbiae, Gi. ewarti, Gi. gowdeyi, and Gi. madagascariensis, were described as forming a marsupium at maturity. A fifth species, Gi. longisetosus, forms a marsupium, but Newstead (1911) did not describe this structure in his original description. These species have identical pores, but are widely distributed across the Afrotropical region (South Africa, Nigeria, Uganda, Madagascar and Tanzania, respectively) and we cannot confidently synonymize all of them without further study. Three other species, Gi. bicolor, Gi. cajani and Gi. caudatus (first collected in Ghana, Nigeria and Uganda, respectively) also closely resemble one another and were described originally as lacking an ovisac or marsupium (Newstead), but examination of the type material of Gi. bicolor and Gi. caudatus reveals that they are teneral adult females that had not yet fully formed the marsupium. Gi. cajani was described as an adult female from immature specimens and is possibly a synonym of a member of this group. We compared the third-instar nymph of Gi. cajani and Gi. gowdeyi and found them to be identical, but refrain from synonymizing them without further information. In the key to species of Gigantococcus, Unruh & Gullan (2008b) separated the former five species from the latter three species by the length and density of hair-like setae around the margin of the body. In life, Gi. euphorbiae and Gi. gowdeyi are described as covered in a thick waxy secretion, and Gi. madagascariensis, Gi. bicolor, Gi. caudatus, and Gi. ewarti are described as having waxy tufts forming longitudinal rows. Newstead commented that the specimens of Gi. longisetosus were too badly damaged for him to give an adequate description of the waxy secretion. Other Gigantococcus species The remaining Gigantococcus species (Gi. bimaculatus, Gi. brachystegiae, Gi. maximus, Gi. nigroareolatus and Gi. theobromae) do not resemble one another nor do they resemble any other Gigantococcus or iceryine species. Each species has unique compound multilocular pores not seen in any other species, except for Gi. brachystegiae and Gi. theobromae, which have unique simple multilocular pores in addition to common compound pores. Refer to the comparison section for each of these species for a discussion of unique features. Unruh & Gullan (2008b) were unable to examine material of Gi. rodriguesi, Gi. splendidus and Gi. sulfureus. The original descriptions were not sufficient enough for them to place any of these species into groups. Gavrilov-Zimin (2018) rejected the molecular evidence for the separation of Gigantococcus from Icerya in favor of a phylogenetic evaluation of reproductivde strategies in different "traditionally accepted genera." Based on his morphological definition of the separation of genera, he considered Gigantococcus a subjective synonym of Icerya. Therefore, he reassigned all species in Gigantococcus to the genus Icerya
• General Remarks: Definition and characters (based on adult female, adult male and first instar) by Pesson & Bielenin (1966). Definition and characters (based on adult female and first-instar nymph) by Unruh & Gullan (2008).

Keys

• Watson2022: pp.320-321 ( Adult (F) ) [Monophlebidae in continental Africa]
• UnruhGu2008: pp.23-24 ( Adult (F) ) [Genera of Monophlebidae - Iceryini]
• UnruhGu2008: pp.24 ( First instar ) [Genera of Margarodidae - Iceryini]
• UnruhGu2008b: pp.50-51 ( Adult (F) ) [Species of Gigantococcus]
• UnruhGu2008b: pp.22 ( Adult (F) ) [Genera of Iceryini]

Associated References

• BenDov2005a: catalog, taxonomy, pp. 180
• Foldi2001a: taxonomy, pp. 201
• HodgsoFo2006: taxonomy, pp. 150
• PessonBi1966: description, taxonomy, pp. 219-251
• UnruhGu2008: description, molecular data, phylogeny, taxonomy, pp. 8-50
• UnruhGu2008b: description, taxonomy, pp. 49-51
• Watson2022: distribution, key, pp. 320,333

19 Species