LIBRARY OF THE UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN 590.5 FI V.39 cop. 3 NATURAL HISrORV, SURVEY i.. • d FIELDIANA: ZOOLOGY A continuation of the ZOOLOGICAL SERIES 0/ FIELD MUSEUM OF NATURAL HISTORY VOLUME 39 NATURAL HISTORV PURVEY FEB 11 1971 IIRR4RY FIELD MUSEUM OF NATURAL HISTORY CHICAGO, U.S.A. \^ FIELDIANA . ZOOLOGY ^^ *^^ Pvhliihed hy of>»5 CHICAGO NATURAL HISTORY MUSEUM Volume 39 June 24, 1960 No. 36 A New Genus of Blind Beetles From a Cave in South Africa Henry S. Dybas AssociATB Curator, Division of Insects Among the minute feather-wing beetles collected by Borys Malkin in various parts of Africa during 1948^9 are specimens of a new genus of pale, blind, wingless Ptiliidae found in bat guano in Cango Caves, Cape Province, South Africa. The only Ptiliidae previously found in caves were recorded from Europe. Ptenidium coecum Joseph (Joseph, 1882), found in two caves in Trieste Province, is described as eyeless, wingless, and pale yellow. In these respects it contrasts sharply with other species of Ptenidium found outside of caves. It is said to be related to P. laevigatum Erichs., a common species found in a wide variety of situations in Europe and North Africa (Horion, 1949) but occurring chiefly in de- caying vegetation, animal dung, and mammal nests; it has also been recorded a few times from caves (Wolf, 1934-38). Recently, another species, P. ponteleccianum Strassen (1955), has been described from a single individual found in a cave in Corsica. This species is also related to P. laevigatum but it lacks the vestigial features of P. coecum. The other records of Ptiliidae from caves (Wolf, 1934-38) are those of four European species that are normally found in other habitats and are probably only accidentally or occasionally present in caves. The new genus from Africa shows many of the features associated with cavemicoly — it is blind, wingless, and pale in color. Many species of Ptiliidae found outside of caves, however, are dimorphic or polymorphic with respect to these characters. A number of genera such as Ptinella and Pteryx, which occur mostly in logs, under bark, and in tree-holes, have both normal and vestigial individuals in nearly all the described and undescribed species that I have examined. The vestigial individuals are usually much more numerous than the normal ones and in many species the eyes, wings, and body pigmentation are as much reduced as in the new African genus. This Library of Congress Catalog Card Number: 60-1 Jf8J^2 No. 889 399 NATURAL HISTORY SURVEV IW 0-7 .n.. ^'fiRA«^ 400 FIELDIANA: ZOOLOGY, VOLUME 39 situation is virtually unparalleled in the entire order of the Coleoptera and merits future examination and analysis. While all the specimens in the large sample (more than 350 specimens) of the Cango Cave genus are vestigial, there is still the possibility, in view of the preva- lence of dimorphism in the Ptiliidae, that normal individuals may be found in the future. In the same cave, Borys Malkin collected pale beetles of the family Carabidae. Simon (1896) described a new genus and species of spider, Phanotea peringueyi, of the family Agelenidae, from Cango Caves. It was described as not being blind but with eyes smaller than the non-cavernicolous genera it most approached. An account of the geology of Cango Caves has been recently published by King (1952). A brief account of collecting in Cango Caves is included in a popular article by Borys Malkin (1952). Malkinella, new genus. Figures 68, 69. Type species. — Malkinella cavatica, new species. A pale, blind, wingless genus; form convex, oval; elytra truncate at apex; head with an antennal groove beneath that is continuous with a similar groove on the under side of the prothorax, both grooves with the inner edge produced as a shelf. Mesosternum with the med- ian portion overlying the mesocoxae and continued anteriorly as an obtuse carina. Hind coxae small, separated by about half their width; metasternum lateral to coxae produced for the reception of part of the hind femora. Apex of abdomen without teeth. Form oval, convex. Head broad, deeply inserted into the pronotum. Eyes vestigial, not evident on slide preparations. Antennae (fig. 69, a) long, 11-seg- mented; segments 1-2 large; segment 3 inserted deeply into 2, tapering apically; segments 4-8 subcylindrical, approximately twice as long as wide, each with a sub-median whorl of about 6 long setae as well as a sub-basal whorl (except seg- ment 4) of much smaller setae; segments 9-11 enlarged, 10 and 11 each with pale vesicular setae beyond the middle and with scattered normal setae, as well as the median whorls of about six strong, curved setae and the basal whorls of finer setae. Pronotum (fig. 68, c) about twice as wide as long, sides evenly curved, widest at base, overlapping scutellum and base of elytra; very convex in cross section, sides meeting hypomera at an acute angle. Hind angles obtusely rounded, not produced. Scutellum broad, partly covered by pronotum. Elytra (fig. 68, c) trun- cate, together a little broader than long. Epipleuron (fig. 68, d) extending one-half length of elytron. Wings vestigial, not evident in slide preparations. Under side of head (fig. 68, e) with antennal grooves delimited ventrally by a shelf-like projection of the genal area. Mentum trapezoidal. Maxillary palpi 4-segmented. Tentorium with a median spur projecting anteriorly from the trans- verse bar. DYBAS: A NEW GENUS OF AFRICAN BEETLES 401 Prostemum (fig. 68, d) short in front of coxae, shorter than least diameter of coxal acetabulum. Mesosternum (fig. 68, d) carinate in front of coxae. Mesocoxal acetabula broadly contiguous internally. Mesopleural-metastemal suture directed later- ally, convex anteriorly. Metasternum (fig. 68, d) more than three times as broad as long, projecting posteriorly between the hind coxae, which are separated by about one-half their width and by about one-tenth of the metasternal width. Lat- eral to the coxae, the metasternum is produced and partly covers the hind femora when they are retracted. Metendosternite with two divergent, dorsally ascend- ing arms. Abdomen not completely covered by the elytra, apical dorsal segments (IX and X) separate, pygidium (tergum X) without teeth. Tergum VII without the micro-pectinate hind margin that is characteristic of the Ptiliidae (Dybas, 1956). Six visible ventral segments, the first one impressed on each side for the reception of the hind femora. Legs moderately short (fig. 69, b-d); posterior coxae small, subtriangular, lam- inate, separated by less than half their width; tarsi slender; tarsal claws simple. Aedeagus (fig. 68, a) an asymmetrical curved tube without evident lateral lobes. Remarks. — Malkinella is immediately distinguished from all other described Ptiliidae by its unique antennal grooves on the under side of the head and prothorax. The systematic position of the genus within the family is difficult to establish at present because of the lack of an adequate classification of the Ptiliidae. Malkinella re- sembles the Acrotrichis group in general habitus but the resemblance is superficial. Acrotrichis and its allies form one of the most dis- tinctive groups in the family. In that group the pygidium and form of aedeagus are diagnostic. The pygidium is composed of terga IX and X fused, the presence of tergum X being indicated by a tooth on each side. The aedeagus of the male consists of a short sym- metrical tube bearing a pair of hooks on the ventral surface. The new genus has truncate elytra but lacks the distinctive char- acters of the pygidium and aedeagus of the Acrotrichis group. In these structures it resembles the pterycine group (Dybas, 1955) and is tentatively placed there, but it is not closely related to any de- scribed genus. Malkinella cavatica, new species. Figures 68, 69. Description (of dry paratype): Yellow-brown, shining; covered with fine, golden, moderately sparse, recumbent setae that are inserted in transverse, irreg- ular rows. General form oval, strongly convex. Head deeply inserted into apical fora- men of pronotum, its anterior margin broadly arcuate. Antennae reaching to near base of pronotum. Pronotum at base overlapping scutellum and base of elytra, less than twice as wide at base as long; hind angles overlapping humeri, obtusely '>>■. k Fig. 68. Malkinella cavatica, new gen. and sp. a, Aedeagus, ventral view. b, Spermatheca, ventral view (same scale as a), c, Dorsal view, d, Ventral view, composite drawing, e, Head capsule, ventral view. 402 1 DYBAS: A NEW GENUS OF AFRICAN BEETLES 403 rounded from side view; pronotum widest just anterior to hind angles, thence in- creasingly curved to the apical foramen, which is one-half its basal width; sides finely margined, hypopleurae inflected at an extremely acute angle, nearly vertical. Scutellum very broadly triangular, nearly completely concealed by base of prono- tum. Elytra together a little wider at base than long, each side slightly expanded. O.I mm. '^^^^, Fig. 69. Malkinella cavatica, new gen. and sp. a. Left antenna, ventral view. b, Anterior left leg, posterior view, male, c. Middle left leg, anterior view, d. Pos- terior left leg, anterior view. margined, with a sharply infllexed epipleuron that is broadest at the humerus and then narrows to about the apical third of the elytron; sides slightly sinuate, converging gradually to near the apex, thence gradually rounded to the broadly truncate apices, which are a little rounded at the suture. Abdomen with the last three segments variously contracted. Male with aedeagus as in figure 68, a. Female with spermatheca as in figure 68, b. Legs and antennae as in figure 69, a-d (drawing from microscope slide preparations). Measurements: Length (to apex of elytra) 0.80 mm.; width 0.48 mm.; depth 0.31 mm. Holotype. — A female, mounted on a microscope slide, from Cango Caves, Oudtshoom, Cape Province, South Africa; collected October, 404 FIELDIANA: ZOOLOGY, VOLUME 39 1949, in bat guano, by Borys Malkin. In the collection of Chicago Natural History Museum. Allotype. — A male, same data as holotype, mounted on a micro- scope slide. Paratypes. — A total of 369 specimens (not including fragmentary material), same data as the holotype; 5 mounted dry, 16 on micro- scope slides, and 348 in alcohol. In the collection of Chicago Natural History Museum except for 24 paratypes deposited in the collection of the Transvaal Museum, Pretoria, South Africa, and 12 paratypes deposited in the collection of the Institute Scientifique de Madagas- car, Taimbazaza-Tananarive, Madagascar. Remarks.— According to the notes of the collector, the specimens were collected in the cave in the first and largest chamber, which is about 200 feet long and nearly 70 feet high. There were thousands of bats present and their guano covered the floor of the cave to a depth of nearly 4 inches in places. In this guano, the ptiliids were present in great numbers. Of 309 sexed individuals, 148 are females and 161 males. Two associated ptiliid larvae were also collected. I am pleased to name this distinct new genus for my friend, Borys Malkin, whose collections of Ptiliidae, made in many parts of the world, contain a wealth of new and interesting material. REFERENCES Dybas, Henry S. 1955. New feather-wing beetles from termite nests in the American tropics (Coleoptera: Ptihidae). Fieldiana, Zool., 37: 561-577, 7 text figs. 1956. A new genus of minute fungus-pore beetles from Oregon (Coleoptera: Ptiliidae). Fieldiana, Zool., 34: 441-448, 3 text figs. HoRiON, Adolf 1949. Faunistik der Mitteleuropaischen Kafer. 2. Palpicornia-Staphylinoidea (ausser Staphylinidae). xxiii+388 pp. (Ptiliidae, pp. 226-252). Frankfurt- am-Main. Joseph, Gustav 1882. Systematisches Verzeichniss der in den Tropfstein-Grotten von Krain einheimischen Arthropoden nebst Diagnosen der von Verfasser entdeckten und bisher noch nicht beschriebenen Arten. Berlin Ent. Zeitschr., 26: 1-50. King, Lester 1952. The geology of the Cango Caves, Oudtshoorn, C. P. Roy. Soc. S. Africa Trans., 33: 457-468. Malkin, Borys 1952. Africa south. Pacific Discovery, 5: 24-30. DYBAS: A NEW GENUS OF AFRICAN BEETLES 405 Simon, E. 1896. Description d'un Arachnide cavernicole de I'Afrique australe. Bull. Soc. Ent. Fr., 18%: 285-286. Strassbn, Richard Zitr 1955. Eine neue Ptiliide aus Korsika (Ins., Col.). Senck. Biol., 36: 215-218, 1 text fig. Wolf, Benno 1934-38. Animalium cavernarum catalogus. 3, 918 pp. (Ptiliidae, pp. 356-357). Junk, 's-Gravenhage.