Pheidole flavens Roger

Sarnat, Eli M., Fischer, Georg, Guenard, Benoit & Economo, Evan P., 2015, Introduced Pheidole of the world: taxonomy, biology and distribution, ZooKeys 543, pp. 1-109 : 26-29

Taxon classification Animalia Hymenoptera Formicidae

Pheidole flavens Roger Figs 77, Fig. 88d

Pheidole flavens . Pheidole flavens Roger 1863a: 198 (s.w.q.) CUBA. Wheeler, W.M. 1905: 92 (m.). Neotype designated: Barrajagua, Las Villas, CUBA (E.O. Wilson): Wilson 2003: 419.

Pheidole tuberculata . Pheidole exigua var. tuberculata Mayr 1887: 585 (s.) St. Catharina, BRAZIL. Subspecies of flavens : Emery 1894: 157. Junior synonym of flavens : Wilson 2003: 419.

Pheidole vincentensis . Pheidole flavens var. vincentensis Forel 1893a: 411 (s.w.q.m.) SAINT VINCENT. Junior synonym of flavens : Wilson 2003: 419.

Pheidole gracilior . Pheidole flavens r. gracilior Forel 1901a: 78 (s.w.q.) GERMANY (intercepted in quarantine, from West Indies). Junior synonym of flavens : Wilson 2003: 419.

Pheidole haytiana . Pheidole flavens var. haytiana Forel 1907: 6 (w.) HAITI, Port-au-Prince (Keitel). Wheeler, W.M. & Mann, 1914: 24 (s.q.m.). Junior synonym of flavens : Wilson 2003: 419.

Pheidole spei . Pheidole flavens st. spei Santschi 1930: 77 (s.w.) CUBA, Pinar del Rio, Punta Esperanza, 4.i.2030, 7 s., 10 w. (Bierig). Junior synonym of flavens : Wilson 2003: 419.

Pheidole aechmeae . Pheidole floridana subsp. aechmeae Wheeler, W.M. 1934: 166 (s.w.) MEXICO, Camaron near Mirador, Vera Cruz, in Aechmea bracteata , No. 472 (Skwarra). Junior synonym of flavens : Wilson 2003: 419.

Pheidole greggi . Pheidole greggi Naves, 1985: 62, figs. 21, 45, 57 (s.w.) U.S.A., Miami, Florida, 19.xii.1945 (W.F. Buren). Junior synonym of flavens : Wilson 2003: 419.

Diagnosis among introduced Pheidole .

See notes under Pheidole flavens -complex. Neotype major: HW 0.72, HL 0.74, SL 0.42, CI 103, SI 58. Paraneotype minor: HW 0.34, HL 0.42, SL 0.34, CI 124. SI 100. Non-type measurements, major: HW 0.68-0.83, HL 0.74-0.88, SL 0.39-0.42, CI 87-97, SI 52-59. Non-type measurements, minor: HW 0.34-0.45, HL 0.39-0.49, SL 0.34-0.42, CI 81-93, SI 89-104.

Identification, taxonomy and systematics.

Pheidole flavens belongs to the Pheidole flavens -complex along with a putatively large number of other nominal taxa. However, the Pheidole flavens group as conceived by Wilson (2003) is now known to be polyphyletic ( Economo et al. 2015; Moreau 2008). Readers are referred to the Pheidole flavens -complex for additional discussion of identification, taxonomy and systematics. The taxonomy of Pheidole flavens and its close relatives remains in a state of confusion. It is beyond the scope of the present study to resolve this issue, but we contribute the following discussion as a step towards that goal.

Pheidole flavens was originally described by Roger from Cuba, but the type material is considered to be lost. Wilson (2003) designated a neotype from Cuba and synonymized a total of eight nominal taxa with Pheidole flavens . Of these, Pheidole greggi Naves (Florida) and perhaps Pheidole flavens st. spei Santschi (Mexico) are most similar to the Cuban neotype. They, together with the types of Pheidole moerens subsp. creola, are the only specimens examined thus far that have clearly reticulated rugulae posterior to the scrobes of major workers. Naves’ (1985: fig. 55) concept of Pheidole flavens Roger, at least as evidenced by his figures and descriptions, more closely matches our concept Pheidole navigans , a species that is spreading across the southeastern United States. The syntype major of Pheidole flavens var. vincentensis Forel differs substantially from the neotype in that the head is completely glossy between the rugulae, which are themselves entirely longitudinal and do not extend far beyond the maximum extent of the antennal scapes in repose. These characters make it at least superficially more similar to Pheidole moerens and Pheidole navigans . Pheidole flavens r. gracilior and Pheidole navigans were both described by Forel from workers intercepted at a Hamburg quarantine facility, which is testament to the dispersive ability of this complex. The syntype major of the latter species and that of Pheidole floridana subsp. aechmeae Wheeler, also described from Mexico, are quite similar. Pheidole exigua var. tuberculata Mayr has the strongly convex head and promesonotal dome of Pheidole exigua Mayr, and also exhibits tuberculate angles on the mesonotal declivity. Type specimens of Pheidole flavens var. haytiana Forel were not examined for this study.

The only material from outside Central America and the Caribbean that we were able to confirm as matching the Wilson’s neotype was from Florida. The Florida populations referred to here as Pheidole flavens and Pheidole navigans are almost certainly heterospecific. We suspect that Nearctic records of Pheidole flavens outside of Florida such as those reported from Louisiana ( Colby and Prowell 2006; Dash and Hooper-Bùi 2008) refer to either Pheidole bilimeki or the species we are treating as Pheidole navigans in the southeastern USA.

Biology.

The biology of Pheidole flavens , as currently conceived, was reviewed by Wilson (2003) with contributing observations by Jack Longino. The species prefers rotting wood, but also nest beneath the bark of trees, in dead knots on tree trunks, in sod on rocks, in the soil beneath stones, and in epiphyte masses. In the Caribbean it is recorded from forests and thickets from sea level to 900 m, and in Costa Rica it occurs in both wet and dry forests below 1000 m. The nest galleries are diffuse and irregular. Mature colonies are large containing up to thousands of workers. Workers collect small arthropods and will recruit to sugar baits.

Distribution.

Pheidole flavens is among the most widespread and abundant species of its genus in the New World, although this range might be representative of multiple cryptic species. As currently conceived, however, we consider Pheidole flavens native from southern Mexico east through the Caribbean and south to Uruguay and northern Argentina. It is difficult to know whether the disjunction separating the western and eastern regions of South America is accurate or a sampling artifact. The Florida population is believed to have derived from an accidental introduction by commerce ( Deyrup et al. 2000; Wilson 2003).

Risk statement.

Pheidole flavens (or at least it’s very close relatives) are easily transported long distances, and are known to hitchhike with fresh plant material ( Wilson 2003). However, the species is not known to cause significant impact to agricultural systems or native ecosystems, and is not considered a house pest ( Hedges 1998; Klotz et al. 1995).