Gelae

For the ancient people, see Gelae (Scythian tribe) and History of Gilan.

Gelae (/ˈdʒɛli/) is a genus of round fungus beetles belonging to the family Leiodidae.^[2] The beetles are found in different parts of Central and North America. They are small and rounded, feeding on slime moulds. They were originally placed in the genus Agathidium following the discovery of the first species, G. cognatum, in 1878.^[3] The taxonomic position was revised with description of new species in 2004 by American entomologists Kelly B. Miller and Quentin D. Wheeler. Upon creation of the new genus, the five new species are Gelae baen (sounding like "jelly bean"), G. belae ("jelly belly"), G. donut ("jelly doughnut"), G. fish ("jelly fish"), and G. rol ("jelly roll").^[1][4]

Gelae
Gelae cognatum
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Coleoptera
Family:	Leiodidae
Subfamily:	Leiodinae
Tribe:	Agathidiini
Genus:	Gelae Miller and Wheeler, 2004[1]
Type species
Gelae donut Miller and Wheeler, 2004
Diversity
8 described species

Discovery and taxonomy

The first species of Gelae discovered was Agathidium cognatum (now Gelae cognatum). John Lawrence LeConte discovered the only specimen at Marquette, Michigan, near Lake Superior, in 1878.^[3] Another specimen was found by Andrew Matthews in 1887 from the mountains of Totonicapán in Guatemala, and placed it under the then known genus Agathidium. Henry Clinton Fall collected the third species in 1934 from Sugar Pine, California, US.^[5] In 1998, Stewart Blaine Peck, Pedro Gnaspini and Alfred F. Newton Jr. reported the occurrence of closely related but distinct species from their extensive cataloguing of round fungus beetles. They noted that the species had unique features different from Agathidium and other beetles, and labelled them under "Undescribed Genus 7".^[6] With reexamination of the tribe Agathidiini to which they belong, they were reclassified under a new genus Gelae in 2004. Kelly B. Miller and Quentin D. Wheeler described their significant characters and regrouped them, along with five new species, G. baen, G. belae, G. donut, G. fish, and G. rol.^[7] They derived the name from a Latin word gelatus, which means "congealed" or "jellied", and to be pronounced like the English word "jelly". This refers to the slime moulds in which they were found. The species names are merely wordplays without any taxonomical jargon, and are simply "whimsical arrangement of letters", as the authors noted.^[1]

Description

Species of Gelae are small and almost spherical beetles, with highly curved and dome-shaped backs. As with other agathidiines, their food source is slime moulds. According to a cladogram published in 2014, they are most closely related to Liodopria under the same tribe, and are considered as sister taxa.^[8] In contrast to other round fungus beetle, Gelae have exactly 11 antenna segments (antennomeres), the antennomere VII being similar in size and shape to antennomere VI, and an antenna club with three segments. An extension behind the eye called postocular temporum and its surrounding ridge called supraocular carina, found in other beetles, are absent. The middle front head region called the anterior clypeus is also comparatively extended. In addition the elytra (forewings) are moderately lined with punctures, and do not form longitudinal series.^[1]

Species

As of 2014, there are eight valid species of Gelae, as below:^[1]

1. G. fish Miller and Wheeler, 2004 was actually discovered first in 1977 from Chiriqui, Panama.^[1] It is also found throughout southern Mexico and Central America. It is relatively small compared to other species, measuring only 1.84–1.88 mm in length and 0.41–0.48 in breadth. It is mostly brown, with patches of yellow-brown, in colour. It has distinct male genitalia. The genital part has a pair of extended stick-like projections.
2. G. belae Miller and Wheeler, 2004 was discovered in 2003 from Oaxaca, Mexico.^[1] It is also quite small, measuring 2.10–2.14 mm in length, and 0.25–0.27 mm in breadth, and is more spherical. Its head is narrow towards the posterior. The body is yellow-brown in colour, with yellow antennae.
3. G. baen Miller and Wheeler, 2004 was also discovered in 1986 from Oaxaca, Mexico.^[1] It is not known in any other region. Its body is moderately large and measures 2.45–3.26 mm in length, and 0.47–0.51 mm in breadth. Its main body is yellow, with brown elytra and margins, and yellow antennae. Its head is broad and sharply constricted behind the eyes.
4. G. donut Miller and Wheeler, 2004 was discovered in 1983 from Cerro Carpish, Peru.^[1] It is found only in the highlands of Peru and Bolivia. It is the largest species measuring 3.03–3.46 mm in length and 0.45–0.46 mm in breadth. It is mostly brown, but with yellow appendages. Head is not too broad and is dorsally flattened. Elytra is also very big.
5. G. rol Miller and Wheeler, 2004 was discovered in 2002 from Workman Creek, Sierra Ancha, Arizona.^[1] It is found only in the mountains of southern Arizona. It is large-sized measuring 2.75–2.76 mm in length and 0.46–0.48 mm in breadth. It is brown on most of its body but with yellow-coloured appendages.
6. G. parile (Fall, 1934) was first discovered from Sugar Pine, California.^[5] It is found in all parts of US and Canada. Externally, it is very similar to G. parvulum. Its head is moderately constricted. Unlike other species, its middle body margin is not sharp, while the terminal region is very sharp. It measures 2.28–2.47 mm in length, and 0.46 mm in breadth. The main body is brown, while the peripherals, legs and antennae are yellow-brown.
7. G. parvulum (LeConte, 1878) was discovered from the shores of Lake Superior.^[9] Other than the original location. further specimens are collected so far only in California It is quite robust with body length of 2.35–2.55 mm and breadth of 0.48–0.52 mm. Its colour and most external features are similar to those of G. parile. But it has sharp lateral margin, and large median lobe in male.
8. G. cognatum (Matthews, 1887) was the first species discovered.^[10] It is found in Mexico, Guatemala, Panama, Honduras and Costa Rica. It is a medium-sized species measuring 2.30–3.01 mm in length and 0.47–0.50 mm in breadth. Its body is mostly brown with tinges of yellow and yellow-brown in some parts.

References

1. Miller, Kelly B.; Wheeler, Quentin D. (2004). "Two New genera of Agathidiini from the Nearctic and Neotropical regions (Coleoptera: Leiodidae)". The Coleopterists Bulletin. 58 (4): 466–487. doi:10.1649/633. JSTOR 4009828. S2CID 85779928.
2. Majka, Christopher; Langor, David (2008). "The Leiodidae (Coleoptera) of Atlantic Canada: new records, faunal composition, and zoogeography". ZooKeys (2): 357–402. Bibcode:2008ZooK....2..357M. doi:10.3897/zookeys.2.56.
3. Angelini, F (2010). "World Catalogue of the Tribe Agathidiini (Coleoptera, Leiodidae, Leiodinae)" (PDF). Annali del Museo Civico di Storia Naturale "G. Doria". 102: 1–157.
4. "Bizarre Beetle Branding - Etymology meets Entomology". h2g2. 5 June 2006. Retrieved 12 November 2014.
5. Fall, Henry C. (1934). "A review of the North American species of Agathidium". Entomologica Americana. 14 (3): 117.
6. Peck, S.B.; Gnaspini, P; Newton Jr., A.F. (1998). "Catalogue and generic keys for the Leiodidae of Mexico, West Indies, and Central and South America (Insecta: Coleoptera)". Giornale Italiano di Entomologia. 9 (1): 37–72.
7. Millie (18 February 2014). "Species naming – an alternative view". University of Southampton. Retrieved 9 November 2014.
8. Park, Sun-Jae; Leschen, Richard A. B.; Ahn, Kee-Jeng (2014). "Phylogeny of the Agathidiini Westwood (Coleoptera: Leiodidae) and implications for classification and contractile morphology". Systematic Entomology. 39 (1): 36–48. Bibcode:2014SysEn..39...36P. doi:10.1111/syen.12034. S2CID 86132244.
9. LeConte, J. L. (1878). Hubbard, H. G.; Shwarz, E. A. (eds.). "The Coleoptera of Michigan. Descriptions of new species". Proceedings of the American Philosophical Society. 17: 598. JSTOR 982657.
10. Matthews, A. (1887). "Silphidae". In Godman, F. C.; Salvin, O. (eds.). Insecta. Coleoptera. Vol. II. Part 1. Biologia Centrali-Americana. Vol. Insecta. Coleoptera. v. 2. pt. 1. [Pselapidae, etc.] by David Sharp, Andrew Matthews and George Lewi. London: R.H. Porter. p. 77;Pl. 3, Fig. 2.

External links

• Taxonomy at BioLib
• Classification at Bugguide
• Taxonomy and nomenclature at ITIS Report
• List of species at Global Index Names Archived 2014-11-09 at the Wayback Machine