Purenleon Stange, 2002

Miller, Robert B. & Stange, Lionel A., 2014, A revision of the genus Purenleon Stange (Neuroptera: Myrmeleontidae: Nemoleontini), Insecta Mundi 2014 (384), pp. 1-67 : 3-4

Purenleon Stange

Purenleon Stange 2002: 285 . Type species: Purenleon abruptus Stange , by original designation. = Diazus Navás 1914: 220 (preoccupied by Diazus Leconte, 1859 , Coleoptera : Scarabaeidae ) by Stange

2002: 285.

Further description. Miller and Stange 2011: 17.

Further larval description. Miller and Stange 2011: 17.

Key to species. North America ( Banks 1927: 60–61); Cuba ( Alayo 1968: 65); Hispaniola ( Miller and Stange 2011: 2–3); South America ( Banks 1943: 169).

List of species. Stange 1970 b: 23; 2004: 214–217.

Distribution. West Indies; North America; South America.

Diagnosis. Adult: foretarsus with basal tarsomere no longer than distal one, usually much shorter; basitarsus of hindleg at least 2.5 times longer than wide or midtibia swollen nearly twice as thick as foretibia; forefemur swollen, at widest point wider than interocular distance, with abundant pubescence especially on closing face; femoral sense hair of foreleg elongate, over one-half length of femur; midfemoral sense hair shorter or longer than forefemoral sense hair; tibial spurs present; pretarsal claws not capable of closing against ventral surface of distal tarsomere; forewing costal area narrow to moderately broad near coalescing of subcostal and radial wings, at most 1.5 times higher than at middle of wing, subcostal area not narrowed, at least 1.5 times as wide as radial vein diameter at narrowest point; hindwing not falcate; male ectoproct without postventral lobe; tergite VIII of female terminalia without stout elongate bristle row subapically.

Larva: mandible shorter or longer than head capsule length, with three evenly spaced teeth; basal tooth originates well before mid point of mandible; distance between teeth usually only little longer than distance between basal tooth and mandibular base; labial palpus three segmented; dorsal surface of head capsule usually with scattered dolichasters; mesothoracic spiracle usually borne on tubercle; abdominal spiracles sometimes borne on small tubercle; abdomen without lateral scoli; abdominal sternite VIII without submedian teeth.

Biology. Larvae of Purenleon have been found in diverse habitats such as in cave mouths and rock overhangs (mostly inscriptus group), in sand under Palm fronds ( P. minor ), in sand tracts, and living in loose soil around tree bases. Four species ( P. bistictus , P. minor , P. parallelus , P. reductus ) are found in coastal sand areas. Larvae have specific adaptations to different substrates. Spiracles borne on elongate tubercles are the norm for species living in coarse sand or a sand and organic matter combination. This type of substrate is favored also by species with dolichasters or thick shafted setae. Species in fine dust or sand tend to have shorter spiracular tubercles and finer simple setae. Careful sand testing of substrates by females utilizing the digging setae on their terminalia ensures that larvae hatch in close proximity to microhabitats suited to their physical adaptations, and temperature and light requirements.

Zoogeography. This genus is restricted to the Western Hemisphere although absent in Canada and the eastern United States (east of 100 th meridian). The five species of the inscriptus group are found in the southwestern United States south to Costa Rica. Seven species are restricted to the West Indies with the preponderance of species in Cuba (4 species) and Hispaniola (4 species). Two of the West Indian species, P. bistictus and P. minor are widespread Caribbean species ranging from the Florida Keys to St. Kitts with the former species also found on the Yucatan Peninsula. One endemic species is found in the Cayman Islands and one in Jamaica. The tibialis group with two species is restricted to Venezuela and Colombia. Mexico has the most species, with all five species of the inscriptus group and with eight species of the bistictus group of which three appear to be endemic. Purenleon parallelus Banks is the most widespread species ranging from Mexico to Colombia. Except for the tibialis group in Colombia and Venezuela and P. clavatus (Navás) from Brazil, no other species of this genus are found in South America.

Discussion: This strictly New World genus has three distinct species groups. The inscriptus group has small pretarsal claws that are less than one-half the length of the basitarsus whereas those of the bistictus and tibialis groups are as long as the basitarsus. It should be noted that P. abrupus is tentatively placed in this group based on it’s pretarsal claws but the larvae are very different from other members of the P. inscirptus group. The tibialis group is known from Colombia and Venezuela and has the midtibia greatly swollen, much broader than foretibia and the basitarsus of hindleg is about twice as long as greatest diameter. Also, the posterior margin of sternite VIII of the female of the tibialis group have small lateral lobes. Species of the inscriptus and bistictus groups were originally included in the genus Psammoleon Banks. The adults of Psammoleon differ from those of Purenleon in having specialized setae on tergite VIII as part of the egg throwing behavior of this genus. Most of the larvae of Purenleon are known. In general, species in the genus Euptilon (formerly Psammoleon ) have the rows of setae posterior to the lateral tentorial suture in three or more rows, and only about twice as long as wide, except E. decipiens Banks , which lacks this character altogether. In Purenleon , the setae are generally longer than this and occur in no more than two tows. The exception to this is Euptilon normalis of northern California, where they also occur in two rows and are as elongate as in Purenleon . The Purenleon in this area are members of the inscriptus group, and have no such setae. Only six known species of Purenleon have this character. These are P. abruptus , P. apache , P. aztecus P. toltecus , P. cavei , and P. debilis .