Lepismatidae Latreille 1802
Creators: name: Molero-Baltanás, Rafael
name: Gaju-Ricart, Miquel
name: Smith, Graeme B.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Zygentoma
Lepismatidae

description: Key to genera of Lepismatidae
The number of genera previously known and considered as valid in the family Lepismatidae is 43. As a 44 th genus is erected in this work, and a genus is split into two, the definitive number increases to 45 extant genera. The following key also includes additional fossil genera, but not Apteryskenoma Paclt, 1953 and Panlepisma Silvestri, 1940; these genera remain unplaced, although their potential position in the key is commented on below the key, together with some additional comments.
1. Thoracic sternites reduced, not free and largely covered by coxae, usually with an acute posterior angle (Fig. 8A). Males with paramera (1), thin and tubuliform, without a subapical glandular area (Fig. 12A) ..................................................................................................subfam. Acrotelsatinae 2
– Thoracic sternites developed, covering coxae, frequently with a more or less rounded hind margin (for example, as in Fig. 8 B-D). With or without paramera. If the prosternum is reduced, antennae have specialized bidigitate sensilla (Fig. 2B) and males lack paramera ........................................... 7
2. Head hypognathous, body short and thorax width usually greater than abdominal length (Fig. 17D). Ventral abdominal segments bare, without chaetotaxy. SE Palaearctic ...... Lepismina Gervais, 1844
– Head not hypognathous, body usually elongate and thorax shorter than length of the abdomen. Most ventral abdominal segments with some combs of macrochaetae (usually 2+2 combs on urosternites III–VIII and sometimes one median comb on urosternites I–VII or I–VIII) .................................... 3
3. Urotergite X triangular, with acute posterior margin, with several lateral combs (similar to Fig. 11D) ........................................................................................................................................... 4
– Urotergite X trapezoidal or rounded, with posterior margin more or less straight or rounded but not clearly acute, with 1+1 lateral combs ............................................................................................... 5
4. Hind margins of thoracic tergites with 1+1 combs of macrochaetae. Ovipositor thin, with fine setae apically (primary type). New Guinea .......................................................... Paracrotelsa Paclt, 1967
– Hind margins of thoracic tergites without 1+1 combs of macrochaetae. Ovipositor with some subapical sclerotized spines (secondary type). Pantropical, synanthropic ......................................... ................................................................................................................... Acrotelsa Escherich, 1905
5. Last segment of labial palp with five papillae arranged in two rows (2+3). Some macrochaetae slightly feathered. Setal collar of pronotum covering 50–60% of anterior margin. E Palaearctic (2) .. .................................................................................................................. Desertinoma Kaplin, 1992
– Last segment of labial palp with four papillae arranged in two rows or forming a diamond. All macrochaetae smooth. Without a setal collar on the pronotum, only with 1+1 setal tufts ............... 6
6. Hind margin of urotergite X concave. Without median combs on all urosternites. Yemen ................ ............................................................................................................... Primacrotelsa Mendes, 2004
– Hind margin of urotergite X rounded, convex. Median combs present on one or more urosternites. Australia ..................................................................................................... Anisolepisma Paclt, 1967
7. Macrochaetae smooth, usually bifid apically (Figs 9B, 16A, 16E). Males with paramera .............. 8
– Macrochaetae frequently feathered (Figs 9C, 16C–D, F); if smooth, some may have rounded tip (“false-smooth” macrochaetae, as the bigger ones in Fig. 16E) and urotergal setation is very dense, consisting mainly of wide setal fringes and if grouped, spaces between groups are narrower than groups and these species are found only in Namib Desert dunes. Males lacking paramera .......... 21
8. Anterior margin of pronotum with setal collar (as in Fig. 5A). Antennae usually with a poor diversity of sensilla (basiconic, trichobothria, chaetic and trichoid sensilla). Femora and tibiae with or without scales; if present, these scales are different to those covering coxae and body .................................. ............................................................................................................subfam. Heterolepismatinae 9
– Anterior margin of pronotum without setal collar (as in Fig. 5B), at most one group of anterolateral macrochaetae inserted on each corner (Fig. 5C). Antennae usually with a higher diversity of sensilla; some basiconic transformed into more specialized types such basiconic F sensu Adel (Silvestri’s type, Fig. 2A) or asteriform sensilla (Fig. 2C–D). Femora and tibiae always without scales, only covered with setae (3) .................................................................................. subfam. Lepismatinae 11
9. Femoral and tibial scales wide, rounded, triangular or sub-rectangular. With three or more pairs of styli. Thoracic sternites wide, trapezoidal, with a broad truncated posterior margin. Hind margin of urotergite X rounded. Australia ........................... Visma Smith, Mitchell & Molero- Baltanás, 2021
– Femoral and tibial scales absent; if present, they are lanceolate. No more than three pairs of styli, frequently one or two pairs. Thoracic sternites parabolic or heart-shaped, with a convex posterior margin; if truncate, straight part not wide. Hind margin of urotergite X variable .......................... 10
10. Labrum with thin setae. Urotergite X usually trapezoidal or parabolic, relatively long. One to three pairs of styli. Urosternal combs short of less than four macrochaetae. Widely distributed in S and C America, E Africa, S Asia and Australia ....................................... Heterolepisma Escherich, 1905
– Labrum with macrochaetae and thin setae. Urotergite X very short and slightly convex. Only one pair of styli. Urosternal combs long, especially medially. Japan, coral cays of E Australia .............. ..................................................................................................... Maritisma Smith & Mitchell, 2019
11. Abdominal sternites lacking median combs of macrochaetae ........................................................ 12
– At least some abdominal sternites with a median comb of macrochaetae ...................................... 14
12. Pronotum with 1+1 tufts of macrochaetae on its anterolateral corners. Last abdominal tergite (segment X) triangular, acutely pointed posteriorly. Two pairs of abdominal styli. North America .. .............................................................................................................. Anallacrotelsa Mendes, 1996
– Pronotum without tufts on its anterolateral corners. Last abdominal segment not triangular, with subtrapezoidal shape. One or 3 pairs of abdominal styli. Burmese amber ..................................... 13
13. Three pairs of abdominal styli. Thorax much wider and clearly detached from abdomen base, which tapers visibly to posterior end ................................... Cretalepisma (†) Mendes & Wunderlich, 2013
– One pair of abdominal styli. Body shape almost parallel-sided ......................................................... ......................................................................................... Burmalepisma (†) Mendes & Poinar, 2008
14. Abdominal tergites with combs of macrochaetae, most of them with 3+3 combs. Paramera pseudoarticulated. Urotergite X acutely pointed or subtrapezoidal with convex hind margin. Holarctic extant species and Baltic amber .............................................................. Allacrotelsa Silvestri, 1935
– Dorsal chaetotaxy of abdomen transformed: combs reduced to one or two isolated setae; typical arrangement on a tergite: 1+1 infralateral groups (usually consisting of 1–3 macrochaetae), 1+1 lateral isolated macrochaetae, 1+1 sublateral and 1+1 submedian (in some species or in some tergites one or two of these isolated setae can be absent or there are supernumerary isolated setae, but not forming combs). Urotergite trapezoidal, usually with a straight, slightly concave or convex hind margin ............................................................................................................................................. 15
15. Without asteriform sensilla on antennae and maxillary palps; instead with specialized sensilla of a globular shape (basiconic type F of Adel or Silvestri’s sensilla, wrongly referred to in some papers as campaniform). Paramera well developed, sacciform, in extant forms they attain or even surpass apex of inner process of ninth coxite (Fig. 12B) (4) ......................................................................... 16
– With asteriform sensilla on antennae and usually also on maxillary palps. Paramera small or medium-sized, clearly not attaining apex of inner process of ninth coxite (Fig. 12C) ................................. 17
16. Posterior trichobothrial areas of pronotum closed, encircled by scales and not in contact with edges of notum. Abdominal tergites II–VIII with 3+3 isolated macrochaetae (infralateral, lateral and sublateral). Dominican amber ........................................... Protolepisma (†) Mendes & Poinar, 2013
– Posterior trichobothrial areas of the pronotum open, contacting with lateral edge of notum.Abdominal tergites II–VIII or III–VIII usually with 4+4 isolated macrochaetae (infralateral, lateral, sublateral and submedian); infralateral macrochaetae usually not isolated but forming a group with another macrochaeta and/or with a thin seta. West Palaearctic and Australia, one species synanthropic, cosmopolitan by human dispersal ................................................................ Lepisma Linnaeus, 1758
17. All trichobothrial areas of nota closed, encircled by scales that avoid contact with the edges of respective nota. Clypeus not reduced. Paramera very reduced. S Africa, India, Malaysia, Australia ................................................................................................. Xenolepisma Mendes, 1981
– At least anterior trichobothrial areas of nota open, contacting with edges of nota. Clypeus strongly reduced. Paramera small or medium-sized ..................................................................................... 18
18. Praetarsus with two well developed pulvilli additional to lateral claws and empodium. With 5+5 to 7+7 isolated macrochaetae on urotergites II–VIII additional to infralateral group. E Africa ............. .............................................................................................................. Lepitrochisma Mendes, 1988
– Praetarsus without pulvilli. Usually with 3+3 isolated macrochaetae additional to infralateral group, but variable ..................................................................................................................................... 19
19. Posterior trichobothrial areas of pronotum closed, encircled by scales that avoid contact with edges of notum. Hind tibiae of males not modified. Afrotropical, India ........... Afrolepisma Mendes, 1981
– Posterior trichobothrial areas of pronotum open, contacting edge of notum (Fig. 5B). Hind tibiae of males modified in chaetotaxy and/or shape or not .......................................................................... 20
20. With a row of small macrochaetae on hind margin of nota (5) .................. Tricholepisma Paclt, 1967
– Hind margin of nota without bifid macrochaetae, sometimes with very small, thin and acute setulae (Fig. 5B) ......................................................................................... Neoasterolepisma Mendes, 1988
21. Anterior margin of pronotum devoid of setal collar, at most with a row of a few isolated setae. Papillae of apical article of labial palp arranged in two rows (2+3) .....subfam. Silvestrellatinae 24
– Anterior margin of pronotum with a setal collar. Papillae of apical article of labial palp arranged in a single row (number variable) ....................................................................................................... 22
22. Antennae with bidigitate specialized sensilla (Fig. 2B). Apex of distal article of maxillary palp with a cylindrical sensillum. Prosternum strongly reduced. Mainly in North America ............................. ............................................................................................................ subfam. Mirolepismatinae 23
– Antennae with different types of sensilla, more or less diverse, but lacking bidigitate type. Apex of distal article of maxillary palp without a cylindrical sensillum. Prosternum often slightly smaller than meso- and metasternum, but rarely with a strong reduction (except in Monachina and some psammophilous species) ...................................................................subfam. Ctenolepismatinae 27
23. Chaetotaxy of abdominal tergites consisting of 1+1 infralateral groups of macrochaetae (combs), 1+1 isolated lateral macrochaetae and 1+1 isolated submedian macrochaetae .................................. ............................................................................................................... Prolepismina Silvestri, 1940
– Chaetotaxy of abdominal tergites consisting of 1+1 infralateral groups of macrochaetae (combs), 1+1 combs of macrochaetae in lateral position and 1+1 combs of macrochaetae in submedian position (6) ............................................................................................... Mirolepisma Silvestri, 1938
24. Hind margin of abdominal sternites only with 1+1 isolated or 1+1 pairs of lateral macrochaetae; macrochaetae in median position absent or only present on one abdominal sternite (I or II) ........ 25
– Hind margin of abdominal sternites (at least II–VI) with one or more macrochaetae in median position, in addition to lateral macrochaetae; these can be isolated or forming small combs ........ 26
25. Pronotum with a row of at least 3+3 isolated setae in its anterior margin and at least 2+2 isolated setae inserted on disc, not very close to hind margin. Some urotergites with 1+1 isolated macrochaetae or 1+1 pairs in lateral and submedian positions, not very close to the hind margin. S Africa .................................................................................................. Silvestrella Escherich, 1905
– Anterior margin of pronotum bare, posterior margin with 1+1 isolated setae or 1+1 pairs, inserted very close to hind margin. Most urotergites with 1+1 isolated macrochaetae in lateral and submedian positions inserted very close to hind margin. Afrotropical and occurring in other regions (S America, Sri Lanka, Cape Verde), probably as a result of human dispersal ...................................................... ................................................................................................... Namunukulina Wygodzinsky, 1957
26. Abdominal tergites with 1–2+1–2 infralateral macrochaetae only, lacking macrochaetae in lateral and submedian positions. Hind margin of pronotum bare. SW Africa ....... Hemilepisma Paclt, 1967
– Abdominal tergites with macrochaetae in lateral and submedian positions, in addition to 1+1 infralateral groups of macrochaetae. Hind margin of pronotum with 1+1 isolated lateral macrochaetae. Arabian Peninsula .................................................................................... Hemikulina Mendes, 2008
27. Abdominal dorsal setation of segments I–VIII or II–VIII forming discrete combs on hind margin; at least with 1+1 small infralateral combs and 1+1 isolated macrochaetae, but more frequently consisting of 2+2 or 3+3 bristle-combs on abdominal tergites II–VIII, separated from each other by distances similar to or higher than width of a comb ....................................................................... 31
– Abdominal dorsal setation consisting of a continuous fringe of macrochaetae, not forming discrete combs; if there are separated groups of macrochaetae, distance between them less than width of a group. Genera exclusive to Namib or Palaearctic deserts .............................................................. 28
28. Macrochaetae smooth, some with rounded tip (Fig. 16E) .............................................................. 29
– Macrochaetae feathered. Namib desert ........................................................ Sabulepisma Irish, 1988
29. One pair of abdominal styli. Without a median group of macrochaetae on abdominal sternite VII. Labrum with three tufts of macrochaetae. Palaearctic deserts .................. Mormisma Silvestri, 1938
– Without abdominal styli. With a median group of macrochaetae on abdominal sternite VII. Labrum with two tufts of macrochaetae. Namib desert ............................................................................... 30
30. Antennae clearly shorter than body length. Setal fringes of anterior urotergites with some gaps at each side, forming 3+3 groups of macrochaetae; setal fringes of the last urotergites continuous. Coxal disc with wide transverse bristle-combs ................................... Namibmormisma Irish, 1988
– Antennae as long as body length or even longer. Setal fringes of anterior urotergites without gaps, continuous, with only one median gap in middle, so only 1+1 wide groups of macrochaetae can be distinguished ............................................................................................. Namiblepisma Irish, 2018
31. Abdominal segments I–VIII only with 1+1 infralateral small combs of macrochaetae and 1+1 isolated lateral macrochaetae. There are no urotergites with 2+2 or 3+3 bristle-combs. Afrotropical, including Cape Verde Islands .................................................................. Monachina Silvestri, 1908
– Abdominal segments I–VIII with a higher number of combs of macrochaetae. Some urotergites with 2+2 or 3+3 bristle-combs in infralateral, lateral and submedian positions ..................................... 32
32. Last abdominal tergite triangular or subtriangular, posteriorly acute or somewhat rounded; its lateral margins frequently with more than 1+1 bristle-combs, but sometimes with only 1+1 combs or without defined combs, only with marginal setae. When 1+1 combs are present, they rarely have more than three macrochaetae and are not located close to posterior margin (Fig. 11A–F) .......... 33
– Last abdominal tergite with a different shape (trapezoidal, subtriangular) but not posteriorly acute, convex, straight or slightly convex, usually with quite prominent 1+1 combs near posterior margin (Fig. 11G–O) ................................................................................................................................... 37
33. Abdominal styli on segments III–IX (seven pairs). Lateral combs of urosternites divided by insertion of styli, resulting in 2+2 lateral combs. Antennae with fan-shaped scales (Fig. 15A–B). Terminal filaments covered by scales (Fig. 15F). South America, Caribbean coasts, Galapagos islands, SW Africa (introduced?) ........................................................................................... Stylifera Stach, 1932
– Abdominal styli on segments VIII–IX or VII–IX (2 or 3 pairs). 1+1 lateral combs on urosternites (rarely 1+1 +1). Antennae without fan-shaped scales. Terminal filaments with or without scales .... ......................................................................................................................................................... 34
34. Posterior trichobothrial areas of nota closed (Fig. 7B). Terminal filaments without scales. Caribbean area .................................................................................................................... Caribesella gen. nov.
– All trichobothrial areas open. Terminal filaments with or without scales ...................................... 35
35. Urotergites II–VII with 3+3 combs ................................................................................................ 36
– Urotergites II–VII with 2+2 combs (Australia) ........................................... Qantelsella Smith, 2015
36. Usually two pairs of styli, rarely three or one pair; coxites IX of female usually elongate (three or more times as long as wide at base); coxites IX lacking long transverse combs, although some short combs may occur along inner margins (11) ................................................ Acrotelsella Silvestri, 1935
– One pair of abdominal styli only; coxites IX of female short (less than two times as long as wide at base, with long transverse combs (Australia) ............................................ Hemitelsella Smith, 2016
37. At least some abdominal tergites with 3+3 bristle-combs .............................................................. 38
– All urotergites with at most 2+2 bristle-combs .............................................................................. 44
38. Abdominal tergite I usually with 1+1 bristle-combs, sometimes with 2+2 .................................... 39
– Abdominal tergite I with 3+3 bristle-combs ................................................................................... 42
39. Median bristle-comb of abdominal sternites divided into two combs. Praetarsus without empodium. Namib desert .................................................................................................. Swalepisma Irish, 1988
– Median bristle-comb of abdominal sternites single or absent. Praetarsus with empodium ............ 40
40. All abdominal sternites without median combs or only one small comb on one sternite. Last abdominal tergite of variable shape (trapezoidal with convex, straight or slightly concave hind margin, subtriangular, or short and slightly convex). N and Central America, S Palaearctic, Oriental region, Africa, some species almost cosmopolitan by human dispersal (7) ......................................... ............................................................................................. Ctenolepisma Escherich, 1905 stat. nov.
– Several abdominal sternites with median bristle-combs ................................................................ 41
41. Praetarsal claws normal, empodium smooth. Last abdominal tergite trapezoidal, with its hind margin slightly convex, straight or slightly concave. S Eurasia and Africa ................................................... ..................................................................................... Sceletolepisma Wygodzinsky, 1955 stat. nov.
– Praetarsal claws thin and very long, empodium rugose. Last abdominal tergite short, rounded subtriangular, with its hind margin clearly convex. Southern N America .......................................... .................................................................................................................... Leucolepisma Wall, 1954
42. Each praetarsus with two claws (of similar or different size), without empodium or very reduced .. ......................................................................................................................................................... 43
– Each praetarsus only with a single claw. SW Africa ............................... Nebkhalepisma Irish, 1988
43. Each coxa with one or more transverse bristle-combs. Inner process of coxite IX also with one or more transverse bristle-combs, frequently multiseriate and/or with a large number of macrochaetae. Deserts of S Palaearctic: Sahara, Arabia .............................................. Hyperlepisma Silvestri, 1932
– Coxae lacking transverse bristle-combs. Inner process of coxite IX without transverse comb or with a small comb with few macrochaetae. Namib desert ................................. Gopsilepisma Irish, 1989
44. Abdominal sternites without median bristle-combs. SW Africa ............... Ornatilepisma Irish, 1988
– Several abdominal sternites with a median bristle-comb (8) ............................................................ 45
45. Urotergite X trapezoidal, with its hind margin straight or slightly concave ................................... 46
– Urotergite X subtriangular, with its hind margin convex, more or less rounded (Fig. 11G–H). S Palaearctic and S Africa, some species domestic, almost cosmopolitan by human dispersal (9) ............. .................................................................................................................. Thermobia Bergroth, 1890
46. Abdominal sternites I and II bare; abdominal sternite III with only one median comb. Apical article of labial palp with five sensory papillae. S Africa ................................. Psammolepisma Irish, 1988
– Abdominal sternites I and II with one median comb; abdominal sternites II and III with 1+1 lateral bristle-combs. Apical article of labial palp with three sensory papillae. Mongolia (10) ....................... .................................................................................................................... Asiolepisma Kaplin, 1989
Comments to the key
(1) Parameres are not described for Paracrotelsa, where only the female sex was described by Uchida (1949)
.
(2) The genus Apteryskenoma s. str. has not been included due to its poor original (and only available) description. If it fits with the previous options of this key (i.e., thoracic sternites reduced and covered by coxae, males with thin paramera, ventral abdominal segments with at least 2+2 combs of macrochaetae), it differs from Desertinoma in having six papillae arranged in a single row.
(3) The fossil genera attributed to this subfamily are included here because of the absence of a setal collar; antennal sensilla and scales of legs are not clearly visible in preserved specimens.
(4) Antennal sensilla cannot clearly be seen in the fossil specimen of Protolepisma, but the paramera are large, almost attaining the apex of the inner process of the coxite IX.
(5) Recent genetic and morphological phylogenetic studies suggest that the distinction between Tricholepisma and Neoasterolepisma makes no sense, and that they conform to a single clade. The priority of the name Tricholepisma will eventually give this name to the clade, according to ICZN rules.
(6) According to Mendes (1991), Mirolepisma and Prolepismina should be considered as a single genus.
(7) Heterogeneous group requiring revision, especially of American and some Afrotropical and Oriental species.
(8) Following the description of Silvestri, the genus Panlepisma fits here, but the identity of this genus from Argentina is not clear.
(9) This genus is probably heterogeneous and S African species could be separated into a different genus. Specimens recorded in natural habitats of N. America should be revised, since they probably are more related to Leucolepisma or to a lineage of the heterogeneous Ctenolepisma.
(10) It seems that Kaplin (1989), when describing the new genus Asiolepisma, was not aware of the description of the genus Psammolepisma by Irish, and unfortunately no discussion comparing these genera was included. We have not seen specimens of Asiolepisma, but they seem to be similar to Sceletolepisma from neighbouring areas in other characters, so probably Asiolepisma derives from some Sceletolepisma by losing one urotergal bristle-comb. If this is the situation, Asiolepisma probably lacks scales on the tibiae, and we have observed that Psammolepisma has scales on this article.
(11) The genus Acrotelsella has many undescribed species and is in need of revision. Molecular and morphological studies currently underway have identified two clades within the Australian species currently included under Acrotelsella. Females in one clade have simple, primary ovipositors, sheathed on either side by very long extensions of the inner processes of coxites IX; this clade represents Acrotelsella s. str. The second clade contains species with secondary ovipositors and shorter inner processes on coxites IX, however the molecular data places Qantelsella and Hemitelsella within the same clade. Furthermore, Acrotelsella escherichi Womersley, 1939 was described as having both elongated inner processes but a secondary type ovipositor.
description: Published as part of Molero-Baltanás, Rafael, Gaju-Ricart, Miquel & Smith, Graeme B., 2024, New insights in the taxonomy of Lepismatidae (Insecta, Zygentoma) with an updated key to genera and future challenges, pp. 80-126 in European Journal of Taxonomy 943 (1) on pages 111-117, DOI: 10.5852/ejt.2024.943.2587, http://zenodo.org/record/12634985