Ochthephilus Mulsant & Rey, 1856

Makranczy, György, 2014, Revision of the genus Ochthephilus Mulsant & Rey, 1856 (Coleoptera: Staphylinidae, Oxytelinae), Revue suisse de Zoologie 121 (4), pp. 457-694 : 471-478

Ochthephilus Mulsant & Rey, 1856

Ochthephilus Mulsant & Rey, 1856a: 1 ; type species: Ochthephilus flexuosus Mulsant & Rey, 1856 (by monotypy). – Ancyrophorus Kraatz, 1857: 886 ; type species: Trogophloeus omalinus Erichson, 1840 (subsequent designation by Thomson, 1859: 44). – Misancyrus des Gozis, 1886: 15; type species: Ancyrophorus emarginatus Fauvel, 1871 (original designation). – Psilotrichus Luze, 1904: 69 ; type species: Psilotrichus elegans Luze, 1904 (by monotypy). – Ochthephilinus Eichelbaum, 1915: 104; type species: Ochthephilus flexuosus Mulsant & Rey, 1856 (objective synonym of Ochthephilus ). – Stictancyrus Scheerpeltz, 1950: 65; type species: Trogophloeus flexuosus Fairmaire & Laboulbène, 1856 [syn. of Ochthephilus flexuosus Mulsant & Rey, 1856 ] (original designation).

DIAGNOSIS: Ochthephilus can be recognized by a characteristic “anchorshaped” ridge on the pronotum – in most species well-formed, in a small minority partial. Terminal segment of maxillary palpus quite large and elongate with asymmetrically swollen base, the filamentous sensory structures lay over the swollen side (Figs 32-33). Elytral setation rather short and in most species quite regular. Can be confused (by superficially similar pronotal sculpture) with some Thinodromus species but those either occur in South America or their abdomen posteriorly narrowing more strongly, tarsi shorter (basal three articles compressed); also the formation of tergite VIII in Thinodromus is different, as well as the terminal segment of maxillary palpus.

DESCRIPTION: Small to medium-sized (2. 0-5.3 mm), usually dark brown to black (Figs 481-482), but some species at least partially reddish (Figs 429-430) or peculiarly light coloured, pale brownish-yellowish (Figs 47-48). Body somewhat depressed, moderately densely to densely pubescent, setae regularly spaced and sized in the majority of species. Temples usually moderately well developed, not differing between sexes (no macrocephaly). Head usually smaller (and certainly less broad) than pronotum, latter gently to moderately transverse, posterior corners well-formed, obtuse-angled, but sometimes nearly right-angled. Elytra parallel-sided (only slightly broadening posteriorly), shoulders usually well-developed. Setation in most species regularly spaced and sized, much more so than on head and pronotum. Sutural and outer posterior corners narrowly rounded (except in a few species also with dense, irregularly sized and spaced elytral setation). Abdominal segments moderately shiny with microsculpture and scattered punctation not too conspicuous, only a few species with longer setae on tergites.

Head. Clypeus well-developed, epistomal sulcus (mostly a shinier, transversally sculptured line) present. Dorsum of head with varying strength and density of punctation, usually moderately setose. Supraantennal prominence well developed and separated from vertex by two elongate impressions. Eyes well developed, in the majority of species longer than temples, head at eyes usually wider than at temples. Eye setation generally short (and therefore inconspicuous) but sometimes dense. Gular sutures (Fig. 30) confluent at least anteriorly. Dorsum of head usually with a shallow medial/longitudinal impression connecting epistomal and occipital impressions. Punctation generally more sparse towards middle of vertex, lateral areas (especially near eyes) with microsculpture interferring with punctation. Base of head slightly to strongly constricted to form well-defined/broad neck, but without distinct occipital groove (obsolete; evident as broad, arcuate depression). Antenna slightly incrassate apically, length of segment 3 almost equal to that of article 1 (the longest), segment 2 somewhat shorter, basal disc (ridge) from antennomere 4 onwards quite prominent, all articles with similar sculpture, setation becoming stronger from article 4 onwards. Antennal modification in most species insignificant, but in a number of taxa article 6 unproportionally narrower and shorter than its neighbours (antennomeres 5 and 7) (Figs 353-357); another assemblage of species with a mostly rather conspicuous asymmetrical swelling on one side of antennomere 7 (and in a much smaller extent on article 8) (Figs 70, 95, 117). Compound eyes vary in size, but in most cases prominent, with temples developed (only a few exceptional species with more or less truncate temples) and gently bulging. Labrum undivided, median portion concave but without incisions. Lateral portions bearing large membranous lobes. Epipharynx as in Fig. 1. Mandible (Fig. 3) rather short with somewhat bifurcate apex and one additional, blunt tooth. Prostheca extending from inner edge to at least 2/3 of the length of mandible

FIGS 1-5

Ochthephilus flexuosus Mulsant & Rey ; epipharynx (1), mentum (2), left mandible and apex of right (3), prothorax, ventral view (4), scutellum, dorsal view (5). Scale bar = 0.1 mm for 1-2, 0.12 mm for 5, 0.2 mm for 3, 0.27 mm for 4.

itself, composed of rather long and weak processes. In maxilla, cardo medium sized, triangular, lacinia enlarged with lobe, galea relatively smaller, both with dense setation on apex. Maxillary palpus (Figs 32-33) with first segment very small and ringlike, second rather large with apex broadening, third shorter but wide and less broadening apically and fourth segment almost as broad at base as apex of previous; this terminal segment is of characteristic shape, base bulbous and asymmetrically swollen with sensory filaments on that side (these “filaments” or “fingers” can extend out of the groove in which they are “housed”), apex (Fig. 31) elongate, length similar to that of second article. In labium (Fig. 30 and Fig. 36 in Makranczy, 2006), mentum (Fig. 2) transverse rectangular. Hypopharynx (Fig. 37 in Makranczy, 2006) laterally with row of bulbous setae, none at midline, without coriaceous field, a few coronal pegs (sensillum basiconicum) mostly around midline and near apical edge; with a platelike armature visible in transparent preparations, slightly differently structured in different species groups (Figs 6-22). Labial palps three segmented, second somewhat longer than first and third, second less wide than first, last rather slender. Third segment with a couple of very short sensillae on tip. All segments with coronal pegs at apex.

Thorax. Prosternal process pointed. Scutellum (Fig. 5) with very scattered and short pubescence. Hypomera exposing protrochantins. Pronotum moderately transverse, usually with broadly rounded anterior corners and convex anterior halves of sides, posterior halves often gently concave (may involve multiple very shallow concavities) and posterior corner well-formed, moderately sharp, slightly obtuse-angled to right-angled. Sides and posterior edge with marginal bead, traces of it often observable on anterior margin (Figs 90, 252), at anterior corners sometimes invisible (in dorsal view) due to corners bending down strongly (Figs 447, 509). Metendosternite (Fig. 23) “gingko-leaf shaped”, consisting of a basal stalk, furcal arms poorly developed. – Legs. Tibia (Fig. 379) with mid-tibial spur(s) and spines or rows of stiff setae. Tarsal segmentation 5-5-5 (Fig. 34) with no pseudosegment, basal 3 articles somewhat compressed but still distinct. Ventral setae modified to form tarsal lobes, last tarsomere usually only with sparse setae, but in some species rather setose. – Elytra. Slight marginal bead along parallel elytral suture, epipleural ridge present, elytra rather parallel-sided, very slightly widening posteriorly, usually narrowly rounded both in outer posterior and sutural corners, only in a few species broadly rounded (mainly in sutural corners). Setation rather short, moderately dense and regularly spaced (in a few species more irregular and dense, but not much longer). Elytral apex near sutural corners with a few peculiarly longer setae (Figs 148, 195, 411) and narrow membraneous lobe, mostly confined to near outer corners (Figs 170, 253), rarely extending along entire apical margin (Figs 67, 91).

Abdomen. Abdomen with two pairs of laterosclerites (Figs 25, 27). Intersegmental membrane without brickwall pattern. Second sternite fully developed (Figs 24, 26), a pair of slender (transversal) plate-pieces of what may be thought as remnants of first sternite embedded in concavities on basal edge (Figs 25, 27). Tergal basolateral ridges absent, all sternites without carinae. Fimbriate edge (palisade fringe) on tergite VII either modified medially (see under species treatments) (Figs 64, 65, 451, 466, 480, 497, 513) or unmodified (Figs 223, 386-387). Sternites VII-VIII otherwise lacking peculiar modifications in both sexes, even sternite VIII with very gentle

FIGS 6-22

Platelike armature in hypopharynx. Ochthephilus filum (Fauvel) (6), O. emarginatus (Fauvel) (7), O. californicus sp. n. (8), O. laevis (Watanabe & Shibata) (9), O. biimpressus (Mäklin) (10), O. brachypterus (Jeannel & Jarrige) (11), O. solodovnikovi Gildenkov (12), O. ashei sp. n. (13), O. kirschenblatti sp. n. (14), O. nepalensis (Scheerpeltz) (15), O. schuelkei sp. n. (16), O. szeli sp. n. (17), O. nigerrimus (Cameron) (18), O. hammondi sp. n. (19), O. wrasei sp. n. (20), O. merkli sp. n. (21), O. szarukani sp. n. (22). Scalebar = 0.1 mmfor 6, 8, 13-14, 16-17, 0.09 mmfor 7, 10-11, 15, 0.065 mmfor 9, 12, 18-22.

difference between sexes. Tergite VIII, however, often with characteristic shape providing major diagnostic trait for distinguishing a large portion of species. In males tergite IX paired, ventral sides of anterolateral margins projected, elongate (ventral strut). Sternite IX present as unpaired plate, elongate, apical edge broadly rounded, moderately setose, sides convergent to base. Tergite X unpaired in both sexes, slightly pentagonal in shape, but apex broadly rounded, this plate often strongly modified and shows strong sexual dimorphism. In females tergite IX paired, similar to those in males but ventral strut completely absent, Sternite IX (genital appendages) consisting of a pair of coxites, valvifers and tiny, moderately elongate styli, rather similar in all species.

Male genitalia. Aedeagus (Fig. 37) median lobe bulb-like, moderately sclerotized internal structures (unpaired) with characteristic shape present in majority of species. Inner sclerite (Fig. 37) usually consisting of one distinct piece (IS), but in some species a second, much smaller and weaker sclerotized, more membranous second piece (SS) observable and surrounded by muscles – in everted state of internal sac inner sclerite is more exposed (Fig. 36). Apical opening (AP) simple, moderately elongate (only in a few species very elongate, e.g. Fig. 472). Median face (Fig. 35) membranous, striated band (SB) can also be elongate or short, "croissant-like". Parameres (PR) not wrapping, with a discrete arm (basally). Apical portion of parameres sometimes strongly modified, this can involve an extra but discrete-edged lobe, a membranous lobe or (in one species) a membranous edge turning from inner facies to outer (Fig. 135). Parameres without setae, apex of paramere (PA) sometimes peculiarly broadened (e.g. Fig. 467). Basal orifice (BO) usually well observable, quite large with discrete edge, in corners next to paramere joint (AT) with lobes (OA) either smaller, inconspicuous (e.g. Fig. 49) or quite remarkably developed (e.g. Fig. 467). Basal part of median lobe shell (MS), rather weakly sclerotized, usually rounded. Aedeagus without visible pump and flagellum. – Female genitalia. Spermatheca (Figs 366, 420, 444, 456, 469, 490) weakly sclerotized, so easily unnoticed even in embedded preparation. Receptacle elongate bulb-like, spermathecal gland small and spherical, connected to base of receptacle by long, earthwormlike tube.

DIVERSITY: The genus in the current account includes 62 described species, with a few remaining undescribed (due to insufficient or unsuitable material). Therefore it is a good estimation that when fully known the number of species could go up to 70-80, and most still undescribed species are expected from the Himalaya and mountainous China. Forest destruction and exploitative use of running waters in these latter areas, however, endanger habitats and could prevent discovery of the remaining species.

DISTRIBUTION: Ochthephilus is a Holarctic genus, with the greatest diversity in the Mediterranean area and the Himalayas plus mountainous southern China. Most species occur in montane or premontane areas, a few in lowlands. They are mostly confined to stream- and riverbanks, the majority of species are expected to be rather widespread, all are fully winged, so as long as suitable habitats are not completly destroyed they are not particularly endangered. Exceptions are some of the smallest species that formerly inhabited lowland rivers with predominantly sandy banks FIGS 23-29

(23) Ochthephilus flexuosus Mulsant & Rey ; pterothoracic sterna, without mesocoxae and metacoxae. (24-25) O. filum (Fauvel) ; tergite III plus laterosclerites (24), sternite II, laterosclerite and tergite I, dorsal view (25). (26-27) O. emarginatus (Fauvel) ; laterosclerites of tergite III (26), sternite I (27). (28-29) Female tergite IX; O. praepositus Mulsant & Rey (28), O. rosenhaueri (Kiesenwetter) (29), posterior apex pointing to top. Scale bar = 0.1 mm for 28-29, 0.135 mm for 24-25, 0.2 mm for 26-27, 0.33 mm for 23.

(as opposed to gravel) and are feared as being extinct as uncollected for the last 100 years. Ochthephilus was also found on Canary Islands once, a single male specimen collected by Rafael García Becerra in the northeast of La Palma (Marcos y Cordero *+28.75/-17.78*, 17.VIII.1999), but unfortunately never found again (despite repeated visit of the locality) and based on such insufficient material no new species description can be made .

NATURAL HISTORY: Both larvae and adults are highly hygrophilous and require wet habitats, be it sandy or gravelly banks of rivers and streams (but always running water), or soaking wet moss on rocks. Some species are facultatively cavernicolous. The species which is relatively often found in caves is O. aureus , but occasionally others ( O. angustatus , O. brachypterus , O. tatricus ) are reported, too. As far as it is presently suspected, they feed on algae or various other small particles of freshwater plant material. Almost nothing is known about the life cycle of Ochthephilus . With the exception of O. aureus , which was found in caves most often, and was collected all year round, most specimens were obtained from the spring to autumn months, with the high elevation collections peaking in mid-summer. Specimens are rather rarely recorded to fly to light – although all have developed wings and are capable of flight. This could be partly due to the fact that most light traps are not placed in the vicinity of streams, and it could be that specimens do not fly long distances. On the other hand, a number of specimens were collected by car-nets, indicating that they are frequent fliers. One good example of the varied habitats where adults of Ochthephilus can be found, is O. brachypterus , described from a cave, collected by the present author from moss (High Tatry, 1600 m), gravel-bank of mountain stream (Retezat Mts., 1600 m), but also recorded from car-nets (Kärnten). Almost the same can be said of O. tatricus , and possibly a number of others. Larvae were first mentioned by Ganglbauer (1895), then a tentatively attributed specimen was included in a key to genera by Kasule (1968). Proper larval description of O. aureus was published by Bourne (1975) and larva of the same species was described again by Bruge (2007) without reference to the earlier description. Defensive gland was mentioned in Dettner (1987). Although the genus Ochthephilus is presumably an ancient group within Oxytelinae , no fossils or subfossils are known to the author.

SPECIES GROUPS: Below a conspectus of the herein followed system is given, in order to provide an easier overview. After the valid species names the page number of the respective heading (in bold), the primary habitus illustration(s) and the aedeagus figure (in italics) are listed.