Stewart B. Peck.
Systematics and Evolution of Forest Litter Adelopsis in the Southern Appalachians (Coleoptera: Leiodidae: Catopinae).
Psyche 85:355-382, 1978.

Full text (searchable PDF, 2652K)
Durable link: http://psyche.entclub.org/85/85-355.html

The following unprocessed text is extracted from the PDF file, and is likely to be both incomplete and full of errors. Please consult the PDF file for the complete article.

SYSTEMATICS AND EVOLUTION OF
FOREST LITTER ADELOPSIS
IN THE SOUTHERN APPALACHIANS*
(COLEOPTERA: LEIODIDAE; CATOPINAE)
BY STEWART B. PECK
Department of Biology
Carleton University, Ottawa, Ontario KlS, 5B6, Canada The beetle genus Adelopsis was described by Portevin in 1907, and was proposed for a microphthalmic soil-inhabiting species from Bolivia. Since then, some 20 additional species have been described, and the genus is known to be distributed through the Neotropics from Mexico to southern Brazil and adjacent Argentina. The species are generally large-eyed and winged, and are probably all scavengers of decaying organic matter in mesic tropical lowland and montane forests. They may occasionally occur in caves. The beetles are seldom represented in collections, but they may be frequently collected by sifting forest litter, or by using dung or carrion-baited pitfall traps. My field program of such collecting in the Neotropics since 1966 shows the genus to be far more diverse, abundant, and widespread than indicated in the present literature (Peck, 1977).
Adelopsis was first found to occur outside the Neotropics when I (Peck, 1973) realized that Adelops mitchellensis (Hatch, 1933) from Mt. Mitchell, North Carolina, actually belonged in the genus Adelopsis. Some authors had placed the species in the genus Ptomaphagus. At that time I noted that I also had material of other species from North Carolina, Georgia, Tennessee, Alabama and West Virginia. My indication that they were also in New Mexico was in error (Peck, 1978). The purpose of this paper is to describe these species which occur in forest litter and soil habitats in the southeastern United States, and to consider their distributional and evolutionary history.
Generic diagnosis. The characters are those ofrLeiodidae, Cato- pinae, Ptomaphagini (as given in Peck, 1973). As such they are small beetles with a loose antenna1 club, with segment 8 always smaller than 7 and 9. They have transverse pronotal and oblique *Manuscript received by the editor May I, 1979. 355




================================================================================

356 Psyche [December
elytral strigae, and the summits of their tibiae are armed with a comb of many short and equal spines, as well as by two longer spurs (see Peck, 1973, 1977 and their cited references). Adelopsis is generally difficult to separate from its nearest neighbor, the genus Ptomaphagus, using only external characters. Tropical species of Adelopsis (but not those of the U.S.) usually differ by being smaller (length 2.6 mm or under) and in having the antenna1 club more loosely composed of gradually larger segments, of which the last two are often conspicuously lighter in color. The genera are more reliably separated by the chitinized internal repro- ductive structures of the aedeagus and spermatheca. In Adelopsis the spermatheca (as far as is known) is a more simple curved tube, and the aedeagus has a tip which is more elaborately sculptured, or Map 1.
Distribution of known species of Adelopsis in the southeastern United States. Heavy irregular line indicates maximum extent of Pleistocene glaciations. A, A. mitchellensis. B, A. sieevesi. C, A. alle,qhenyensis. D, A. suteri. E, A. rich- landensis. F, A. appalarhiana. G, A. jonesi. H, A. bedfordensis. I, A. cumberlanda. J, A. scoitsboroensis. K, A. nashvillensis. L, A. fumosa. M, A. aha. N, A. Joanna. 0, A. pisgahensis. P, A. orichalcum.




================================================================================

19781 Peck - Adelopsis in the Southern Appalachians 357 is broader and more blunt. The orifice is dorsally sub-terminal and cuts the left side of the aedeagus as in Ptomaphagus. The south- eastern U.S. Adelopsis species are all forest litter and soil inhabi- tants. They are all wingless and have eyes reduced to a collection of about 20 pigmented facets. These structural features will help to distinguish them from most Ptomaphagus, which are either winged and with larger eyes, or are more subterraneanly adapted (for life in caves) and have more-reduced eyes.
Description. The following applies only to the range of variatio-7 known in the species in the southeastern U.S. Additional details on Neotropical species may be found in Jeanne1 (1936) and Szymcza- kowski (1964, 1968, 1969, 1975). Length 2.3 to 2.6 mm, width 1.2 to 1.3 mm. Form elongate oval, compact, convex (Figs. 1, 2). Color light to dark reddish brown. Pubescent, with numerous short recumbent hairs. Head finely punctured; eyes reduced to collection of about 20 pigmented facets (Fig. 3); eye width 1 /3 width of space from antenna1 base to head margin across eye. Antennae short, compact; club darker, somewhat flattened; reaching from middle to hind margin of pronotum when laid back; segment 3 shorter than 2, segment 6-10 wider than long; 8 over twice as wide as long (segments usually longer and thinner in upper elevation deep-litter species than in lower elevation litter-soil species). Last article of maxillary palp slightly shorter than preceding; conical, thinner. Pronotum widest 1 / 3 before base, 1.4 to 1.5 times as wide as long; hind angles acute, hind margin straight; sides arcuate; covered with seta-bearing punctures strongly to faintly organized into striae. Elytra fused, sides gradually tapering to apex in both sexes; external apical angles broadly rounded; sutural angles rounded; apex oblique; strigae distinct, oblique, composed of seta-bearing punc- tures. Metathoracic (flight) wings reduced to tiny scales. Meso- sternal carina low, its notch distinct. Legs not noticeably short and compact (seemingly adapted for running and not digging); protibiae bowed-in, mesotibiae bowed-out, metatibiae straight; comb of spines limited to tibia1 apex; protibial apex oblique and rounded in both sexes; sexual dimorphism only in protarsi, males with first 4 protarsal segments expanded and spongy-pubescent beneath. Aedeagus curved, stout, blunt, with orifice cutting to dorsal surface through left side; internal sac with curled, short, terminal stylet with surface ridges on one side of tip; about 6 sensory hairs on under



================================================================================

Psyche [December
Figures 1-3. SEM phutorn~crographs of Ade/ops min hellemis (Hatch). 1. Lat- eral view. left proteg removed. 2. Dorsal view. 3. Lateral view or head showing eye reduced to collection of about 20 poorly defined facets.



================================================================================

19781 Peck - Adelopsis in the Southern Appalachians 359 surface of each side of tip. Parameres fused to aedeagus at base; with three terminal hairs. Spiculum gastrale short, thick, less than '4 its length projecting beyond anterior end of genital plates. Sperma- theca thin and curved; anterior recurved and often with flattened crest; posterior end often laterally curved-back on itself. Bionomics.
The known United States species are all inhabitants of moist moss, litter, and soil of forests in the Appalachian Mountain Chain, south of the limits of glaciation, from the lowlands inside the Fall-line to the summits of the highest moun- tains. They are occasionally found in soil-filled rock crevices or under large rocks deeply embedded in forest soils, but are more usually captured by sifting litter and moss and by extracting them with Tulgren-Berlese funnels. The litter at the sides of rotting logs seems to be a favored habitat. They may be locally abundant in association with decomposing fleshy fungi or material richly im- pregnated with fungal hyphae, but some may be taken at dung or carrion baits in forests, or in caves. The frequency with which they have been collected in caves reflects only that this is a way by which a collector can gain easy access to the faunas of deep soils. In caves, the beetles are found near cave entrances only and not in the deep regions of caves. The beetles are not morphologically adapted for caves as such. This is evident when they are compared to cave- evolved species of Ptomaphagus (Peck, 1973), so they should be termed edaphophiles (or endogeans or edaphobites), rather than troglophiles, or troglobites. In litter, they seem to be more fre- quently encountered in the springtime and early summer, probably because they are more commonly present in the upper layers of litter and soil which are cool and moist at these seasons. They probably retreat downwards with the increasing warmth and dry- ness of summer. Records do not indicate it, but I think they would be active and accessible to the collector in the late fall and at certain times of the winter as well.
Life cycle characteristics have been determined only from speci- mens captured on several occasions in Morrison's Cave, Dade County, Georgia, and kept in laboratory culture at 15OC. The techniques are those used in culturing Ptomaphagus beetles (Peck, 1973, 1975). Eggs are laid singly by the females on the soil surface of the culture vessel. These hatch in a mean time of 12 days (range 9-15, n = 7). There seem to be three larval instars, and these feed for about 20 days before constructing a mud igloo or pre-pupation cell,



================================================================================

360 Psyche [December
in which the larvae spend a mean of 14 days (range 12-1 6, n = 7) before pupating. The total larval duration then has a mean time of 34 days (range 23-40, n = 7). The pupal stage lasts for a mean of 20 days (range 14-24, n = 6), and pupal darkening is evident for the last two days before eclosion. The newly emerged adult remains in the pupal chamber for 5 days (n = 3) before emerging. The cycle is similar to that of several litter and cave species of Ptomaphagus at the same temperature (Peck, 1973, 1975, and unpubl.). Total longevity of adults is unknown. Adults of unknown age collected in April lived in culture for up to 10 months. Oviposition frequency could be determined for only one paired female which laid 9 eggs in 30 days at intervals of from 1 to 10 days. The larvae are very similar to those of Ptomaphagus and I am unable to confidently distinguish the two. There is no strong evidence for seasonality in reproduction. In caves (and deep soil?) it may occur whenever moisture and food conditions are suitable and this probably holds for forest litter situations with cool-moist seasons being better than warm-dry ones. Systematics
Methods and Materials.
Specimens were borrowed from the
following collections and curators: American Museum of Natural History (AMNH), Lee Herman; Field Museum of Natural History (FMNH), Henry Dybas; Illinois Natural History Survey (INHS), Milton W. Sanderson; United States National Museum (USNM), John Kingsolver; Museum of Natural History, University of Ala- bama (UANH), Herbert Boschung; Museum of Comparative Zool- ogy (MCZ), John Lawrence and Alfred Newton. Specimens not attributed to these collections are in that of the author. Types are deposited in the Canadian National Collection (CNC) unless other- wise indicated. Initials of collectors who frequently found material are as follows: SBP, Stewart B. Peck, often helped by Alan Fiske, James Peck, and Jarmila Peck; WBJ, the late Walter B. Jones, often helped by A. Flannagan, J. M. Valentine, and others; HRS, Harrison R. Steeves, Jr., often helped by J. Patrick. WRS, Walter R. Suter. All HRS and WRS material is in the FMNH. My collecting methods are described in sufficient detail elsewhere (1973, 1977, and Newton and Peck, 1975) and need not be repeated. This is also true for the methodology of specimen preparation, with one major exception. A scanning electron microscope (SEM) was



================================================================================

19781 Peck - Adelopsis in the Southern Appalachians 361 found to be of great help in viewing and understanding the three- dimensional structure of the tips of the minute aedeagi. With this understanding, they can be more easily interpreted in the usual slide or glycerine jelly mounts and preparations. SEM photomicrographs were used to make the drawings of the aedeagal tips. A set of three views is usually necessary to interpret and understand the geometry of the aedeagal tip. Although a set of about 6 hairs occurs on each side of the undersurface of the aedeagal tip in all species, these have little value in helping to characterize the species. These hairs have been shown on only a few drawings. Internal sacs were fully seen only in polyvinyl-lactophenol slide mounts. Variation.
Little variation is evident in these species, and little is known of variation within the other species of the genus. Variation over the geographic range of a species is known and illustrated only for A. simoni (Portevin), known from Brazil, Venezuela and Mexico (Szymczakowski, 1968) and in A. brunneus Jeannel, from cave and forest sites from Columbia through Venezuela to Trinidad (Szymczakowski, 1975). Apparent variation in spermathecae is partly due to the difficulty in preparing these fragile structures. When material is limited and the normal spermathecal shape is not known with certainty, several may be illustrated. Individual diagnoses are not given in the following species accounts. In all cases it would indicate that the species are character- ized by the combination of characters of their geographic ranges, and of the aedeagal tips, and possibly of the spermathecae. The gender of the genus is treated as feminine, following the use of its author.
The mitchellensis species group
This group is probably not a closely related assemblage, and is used as a grouping of convenience. Each of the five species is clearly defined, and each may be as phyletically old as the cluster of 11 species placed in the following appalachiana species group. 1. Adelopsis mitchellensis (Hatch)
Figs. 1-5, 50
Adelops mitchellensis Hatch, 1933: 208. Synonymy given in Peck 1973: 55. Material seen.
North Carolina. Yancey County. Mt. Mitchell, no other data, holotype male, allotype female, and paratype male 50133, USNM. Mt. Mitchell 4500-6OOO'(=l475-1967 m); 17-24.VI.



================================================================================

362 Psyche [December
1939, E. D. Quirsfeld, 1 male, MCZ. Mt. Mitchell, 6400' (2098 m), 3-10.1V.1967, S. Peck, carrion trap 214 in summit hemlock and moss forest, 1 female. Black Mountains, no other data, 1 female, USNM; 1 female, FMNH. Black Mts., 8.VIII.1911, 2 females, AMNH.
Description.
Aedeagus (figs. 4-5) with dorsal section of tip flattened and projecting posteriorly over orifice on upper left side. Ventral section broad with central ogival point. Spermatheca fishhook-like (fig. 50) with simple posterior portion, and prominent crest on anterior end.
Distribution. The species is probably limited to the Black Mountains of Yancey County, containing Mt. Mitchell, the highest point in the eastern United States (2191 m). This is the only locality known to have two species of Adelopsis, for here A. mitchellensis is sympatric with A. alta. Some early collection records confused these two.
Notes.
The species is probably most common in the upper elevation forests of spruce-fir or birch-maple. Adults have been collected in April, July, August, and September. 2. Adelopsis steevesi n. sp.
Figs. 6, 7
Holotype male and allotype female in CNC. Type data: North Carolina. Macon County. Norton, Coweeta Hydrological Labora- tory, 24.X. 1965,4,000' (1 3 1 1 m), log-litter, HRS. Paratypes: 17 with same data; 12 with same data but 22.V.1965, 4100' (1344 m) rot wood debris.
Description. Dorsal section of aedeagus tip (figs. 6-7) incised, upraised as knob on left, and as flattened vertical blade on right. Ventral section deeply emarginate, nearly same length as dorsal section. Spermatheca similar to that of A. Joanna, A. alta, A. fumosa, A. richlhdensis, and A. suteri.
Etymology.
Named for Mr. Harrison R. Steeves, Jr., of Bir- mingham, Alabama, in recognition of his extensive field collecting of litter beetles in the southeastern United States (collection de- posited in FMNH).
Distribution. The species should be expected in other sites in the vicinity of Highlands, North Carolina.




================================================================================

19781 Peck - Adelopsis in the Southern Appalachians 363 3. Adelopsis alleghenyensis n. sp.
Figs. 8-10, 51, 52
Holotype male and allotype female in CNC. Type data: West Virginia. Pendleton County. 5 mi (8 km) S Witmer, 3000' (915 m), l6.VII. 197 1, SBP, litter Ber. 21 7. Paratypes: 1 1 with same data; Spruce Knob, 3500' (1 148 m), 8.VI. 1967, SBP. Ber. 58,l male and 1 female; Pocahontas County, Hills Creek Falls, l9.VI. 1971, W. Shear, Berlese, 2 males and 2 females.
Description. Dorsal section of aedeagal tip low and simple (figs. 8-10), with recurved flange on left; ventral section broadly pointed, with tip downcurved, extending far beyond dorsal section. Sperma- theca (figs. 51-52) thick and gently curved, anterior crest large. Etymology. The name refers to the northwestern flank of the Appalachians called the Allegheny Mountains, lying along the border of Virginia and West Virginia and extending into Pennsyl- vania.
Distribution. The species probably has a wider range than the known 60 mile (100 km) long NE-SW line along the Allegheny Mountains of West Virginia.
4. Adelopsis suteri n. sp.
Figs. 11, 12, 53, 54
Holotype male and allotype female in CNC. Type data. Georgia. Rabun County. Mountain City, Black Rock Mountain State Park, l5.VI. 1973, W. R. Suter, litter at log under Rhododendron. Para- types: 1 with same data; Black Rock Mountain State Park, 3000' (91 5 m), 21 .VII. 1967,2 males. North Carolina. Macon County. 5 mi (8 km) NE Highlands, 27.X.1969, W. Shear, Rhododendron litter, 1 male. Jackson County, 7 mi (1 1 km) S Cashiers, 1 1 .VI. 1973, White- water Falls, elm-maple pseudofork, WRS, 1 female. Description. Dorsal section of aedeagal tip (figs. 1 1 - 12) inflated, upturned, with broad and shallow depression in middle, equal in length to uniformly emarginate ventral section. Spermatheca (figs. 53-54) with sharp bend in posterior end, which projects strongly above plane of central curved section, anterior crest high. Etymology. Named for Dr. Walter R. Suter of Carthage Col- lege, Kenosha, Wisconsin, in recognition of his extensive collecting



================================================================================

Psyche
[December




================================================================================

19781 Peck - Adelopsis in the Southern Appalachians 365 of litter beetles in the southeastern United States (collections deposited in FMNH).
Distribution. The species is to be expected in other localities in the Coweea Mountains in the vicinity of Highlands, North Caro- lina, which has been found to be a region rich in species of ground dwelling beetles.
5. Adelopsis richlandensis n. sp.
Figs. 13, 14, 55, 56
Holotype male and allotype female in CNC. Type data. North Carolina. Haywood County. Richland Balsam, 6000' (1967 m), 7-26.VIII.1965, S. & J. Peck, carrion trap. Paratypes; three females with same data; and 1 female, Haywood-Jackson Counties, Rine- hart Knob, 6000' (1967 m), 1.VIII.1960, T. C. Barr. Description. Dorsal section of aedeagal tip (figs. 13-1 4) uni- formly rounded, but with slight emargination; sloping downwards from high crest on right to low and flat left side, ventral section uniformly rounded and projecting beyond dorsal section. Sperma- theca as in figs. 55-56, characteristic form not known with certainty. Etymology.
The name refers to Richland Balsam, the type locality, and highest point on the Blue Ridge Parkway. Distribution. There seems little reason to expect only this species on Richland Balsam. Mt. Pisgah, with A. pisgahensis, is on the same mountain ridge and there are no intervening lowland barriers to dispersal of these flightless beetles. Soco Gap and Balsam Gap to the northwest, each above 3000' (1000 m) separate Richland Balsam from the Plott Balsams and Balsam Mountains, but these also seem inadequate barriers to isolate Richland Balsam from species in- habiting these other mountain regions. Intensive collecting should resolve the questions of how these species are distributed with regards to each other.
Figs. 4-18. Structures of Adelopsis. 4. Left lateral view of entire aedeagus of A. mitchellensis, with internal sac (IS), ventral blade of tegmen (VBT), and dorsal (D) and ventral (V) sections of aedeagal tip. 5. Dorsal view of aedeagal tip of A. mitchellensis indicating right (R) and left (L) sides, and dorsal (D) and ventral (V) sections of the tip. 6-7. Dorsal and lateral views, aedeagal tip, A. sleeves/. 8-10. Dorsal, lateral, and posterior view, aedeagus, A. alleghenvensis. 1 1 -12. Aedea- gal tip. A. suteri. 13-14. A. richlandensis aedeagal tip. 15. Internal sac A. appalach- iana. 16-18.A. appalachiana, note that parameres and hairs on ventral surface of ventral section of aedeagus are not shown in most drawings.



================================================================================

366 Psyche [December
The appalachiana species group
This group is seen as a naturally based and closely related phyletic unit. It is based on A. appalachiana, the most widespread species in both lowland and montane regions. Progressive modification of the relatively simple aedeagus (assumed to be generalized and pleiso- typic) in the nominate species could readily produce the other aedeagal types known in the group.
6. Adelopsis appalachiana n. sp.
Figs. 15-18, 57-60
Holotype male and allotype female in CNC. Type data: Alabama. DeKalb County. Fort Payne, Manitou Cave, 1937, W. B. Jones, trap. Paratypes: 49 with same data; 8 with same data except 1939; and the following: Alabama. DeKalb County. Kelly Girls Cave, 1 mi (1.6 km) SE Collinsville, 25.VIII.1965, SBP, 2; Cook Cave (Ala 253), l3.VIII. 1958, WBJ, 2; Lykes Cave, 27.VIII. 1965, SBP, fungus on entrance talus, 22; Cherokee Cave, 4.5 mi (6.5 km) NE Ft. Payne, 15.VIII.1967, SBP, 1. Blount County. Blount Springs, 19.111.1966, SBP, litter in limestone crevice, 1; 7 mi (1 1 km) S Cleveland, outside Horseshoe-Crump Cave, 28.VI.1967, SBP, litter Ber. 70, 2; outside Bangor Cave, 19.111.1966, SBP, rotten tree roots, 4; outside Bangor Cave, 5.1V.1967, SBP, 1; inside Bangor Cave, 20.XII.1965, SBP, 1; near Inland Lake, 28.1X.1958, HRS, forest floor debris, 4. Shelby County. Helena, 3.1.1959, HRS, treehole, 1. Jefferson County. Near Purdy Cave #1, 13.1X.1958, HRS, forest debris in rock crevice, 1. Morgan County. 3% mi (6 km) SE Fayette, 21.V.1972, SBP, Ber 241, litter outside cave entrance, 14. Georgia. Dade County. Mor- rison~ Cave 13.VII.1967, SBP, 6; l6.IX. 1968, SBP, 1; 16-23.VI. 1972, SBP, 3; 4 mi (6.5 km) NE Rising Fawn, 15.VII.1967, SBP, forest litter Ber 78, 4; Johnson Crook Cave #2, 4 mi (6.5 km) NE Rising Fawn, 14.VII. 1967, SBP, 2 in cave entrance; outside Johnson Crook Cave #2, 14.VII.1967, SBP, 6 in litter. Tentatively associated material. Alabama. Etowah County. Wright Cave, 11 .VII.l958, WBJ, 1 male, 1 female. Morgan County, Inge Cave, 2.V.1959, T. C. Barr and HRS, under debris, 2 males. Cleburne County, Cheaha Mountain State Park, 330 m, 13.VI. 1967, SBP, litter Ber 59, 2. Marshall County. Guntersville, near Griffith Cave, 3O.IV. 1960, HRS, 1 female; Kelly Ridge Cave, near Warren- town, 23.VIII.1958, HRS, 1 female. Georgia. Walker County.



================================================================================

19781 Peck - Adelopsis in the Southern Appalachians 367 McLemore Cove, 9 mi (15 km) SW LaFayette, 14.VII.1967, forest log litter Ber 79, SBP, 3. Dawson County. Mt. Oglethorpe, 2000' (610 m), 20.VIII.1967, SBP, litter Ber 80, 1 damaged male. Description. Dorsal section of aedeagus tip (figs. 16- 18) regu- larly curved, unadorned, shortest on left side and longest on right; ventral section regularly curved with downturned tip; posterior view with dorsal section forming a uniformly arched genital orifice, with a uniform border; setae on ventral surface lying in groove rather than separated depressions. Internal sac thick, not narrowed into curved tube at apex (fig. 15). Spermatheca (figs. 57-60) smoothly curved, anterior part broadened and without crest, posterior part recurved off structural plane.
Variation. The Morgan County, Alabama, sample has a lower arch, with a flattened middle to the genital orifice when seen from behind. This opening is most highly arched in the Cheaha Moun- tain, Alabama, male which also has a differing left margin to the ventral section.
Etymology. The name refers to the Appalachian Mountains, around the southern end of which this species is distributed. Distribution. This is the most widely distributed species, ranging from north-central Alabama, south of the Tennessee River, east- wards into northwestern Georgia.
Field Notes. This is the most frequently collected species because it has a wide range, and occurs in a region which has received much collecting attention. It has been found in forest litter and in the entrance zone of caves, in the months of January, March, May, June, July, August and September. It is probably active throughout the year.
7. Adelopsis jonesi n. sp.
Figs. 19-21