Scopaeus spathiferus Coiffait, 1970: 106

Herman, Lee, 2023, Generic Revisions Of The Scopaeina And The Sphaeronina (Coleoptera: Staphylinidae: Paederinae: Lathrobiini), Bulletin of the American Museum of Natural History 2023 (460), pp. 1-195 : 110-118

Scopaeus spathiferus Coiffait, 1970: 106 ,

fixed by monotypy.

— Frisch, Burckhardt, and Wolters, 2002a: 45, 46 (may be distinct genus). — Frisch, Burckhardt, and Wolters, 2002b: 2 (subgenus of Scopaeus ). — Smetana, 2004: 615 (subgenus of Scopaeus ; Palaearctic catalog). — Frisch, 2016: 65 (subgenus of Scopaeus ; characters for Australian species).

DIAGNOSIS: Hyperscopaeus is separated from Scopaeus by the short, apically rounded to diagonally truncate metakatepisternal process (figs. 241, 251) and by the absence of a stridulum, which includes mesofemoral plectral ridges (fig. 253) and a metaventral file near the submarginal ridge (fig. 250, 251). For Scopaeus the metakatepisternal process is long, tapered and apically acute (fig. 104) or short, wide, and apically acute (fig. 94) and a stridulum is present (figs. 90, 92; 104–107). The dorsal side of the median lobe of Hyperscopaeus (fig. 243) has a midlongitudinal division, but for Scopaeus (fig. 158) it is entirely sclerotized and without medial separation.

Hyperscopaeus is separated from Micranops by the position of the trichobothrium, a supraocular trichobothrial depression in the former (fig. 245), and an ovoid postocular trichobothrial cavity in the latter (figs. 266, 282). Similarly, the position of the supraocular trichobothrium adjacent to the middorsal margin of the eye for Hyperscopaeus (fig. 245) separates it from Orus with its trichobothrial canal at the posterior margin of the posteriorly tapered eye (figs. 297, 315, 316). The neck of Hyperscopaeus is exceedingly narrow (fig. 240), about an eighth to a sixth as wide as the postocular width of the head; the neck of Trisunius (fig. 342) is about a third to two fifths as wide as the postocular width of head. The neck of most species of Orus (fig. 286) is about a third as wide as the postocular width of the head; the neck of a few species is narrower, about a fifth as wide as the head. The gular sutures of Hyperscopaeus are narrowly separated to nearly contiguous for most of their length (fig. 244), whereas they are moderately widely separated in Trisunius and Orus (figs. 286, 326). The posterior margin of the head of some species of Hyperscopaeus has a tumescence with a shallow to moderately deep median groove, neither Trisunius nor Orus have this cephalic tumescence. Orus is North American; Hyperscopaeus is from Africa, southern Asia, and Australia.

DESCRIPTION: Body length 2.3–6.6 mm.

Head (fig. 240) with postocular lateral margin nearly straight to broadly and shallowly rounded to basal angle; basal angle sharply rounded; basal margin slightly to strongly sinuo-emarginate, interrupted by small to moderately large median tumescence in some species; tumescence with shallow to moderately deep midlongitudinal groove or sulcus; posteroventral surface (figs. 244, 246) with one or two moderately large to tiny tubercles laterad of lateral margin of neck or tubercles coalescent forming low, elongate ridge or tubercles absent; tubercles, if present, visible (fig. 240) or hidden from dorsal view.

Neck (fig. 240) strongly petiolate; nuchal groove deep and strongly constricted, and base of neck abruptly expanded; neck width across nuchal groove one eighth to one sixth as wide as postocular width of head; nuchal ridge strongly to moderately developed dorsally and laterally.

Dorsal cephalic surface with fine, dense, simple punctation or with tiny puncture on peak of microtubercle; punctation or microtuberculation uniform, but slightly less dense between supraantennal bosses; surface without microsculpturing; surface with dull shine, not polished; pubescence fine, dense, and uniform; macrosetae moderately long, peripheral, and scattered.

Cephalic trichobothrium adjacent to middle of dorsal margin of eye; bothrium in rounded or ovoid trichobothrial depression (fig. 245); trichobothrial depression without setae, but with setae along dorsal margin.

Eyes with posterior margin rounded to slightly flattened to slightly emarginate; corneal lenses of dorsal two or three rows with corneal sensilla (fig. 17, 247).

Gular sutures (fig. 244) narrowly separated, nearly contiguous in some species, and parallel for most of length.

Mandibles: left mandible with three denticles; right mandible with four denticles, basal (third) and subbasal (fourth) denticles well separated or both denticles present as part of large, broad, flat, basal lobe on which third and fourth denticles vary from small to moderately large.

Labrum quadridentate (fig. 249).

Pronotum broadly and shallowly convex to nearly flat; surface with fine, uniform, dense punctation; surface without microsculpturing; midlongitudinal strip moderately punctate or narrow and impunctate; surface with dull shine, not polished; pubescence fine, dense, and uniform; macrosetae present, moderately long, and peripheral or absent; median groove present or absent; midlongitudinal line marked by posteriorly directed setae; posterior margin broadly and shallowly to moderately emarginate; surface with dull shine, not polished; pubescence fine, dense, and uniform; macrosetae moderately long and scattered.

Prohypomeron with postprocoxal lobe separated from remainder of hypomeron by well-developed transverse ridge; lobe with a few setae.

Notosternal suture present.

Elytra longer than or subequal to pronotum; surface with microtubercles; microtubercles with minute, dorsal puncture; surface with fine, dense pubescence; posterior margin with row of setae.

Mesoventrite (fig. 250) with deep, ovoid, median depression.

Mesofurcasternum with internal, median mesofurcasternal apophysis on posteromedial margin present (figs. 241, 250) or absent.

Mesofemur without stridular plectral ridges (fig. 253).

Mesocoxal acetabulum margined by long pericoxal ridge and well developed to more weakly developed near middle (figs. 241, 251).

Metaventrite without stridular file (figs. 251, 252).

Metakatepisternal process short and with rounded to diagonally truncate apex (fig. 241, 251).

Sternite III (fig. 255) without median carina; transverse basal ridge moderately sinuate and with broad, median point.

Sternite IV without apparent glandular pore (fig. 254).

MALE: Sternite VII with surface and posterior margin unmodified or variously modified.

Sternite VIII with emargination of posterior margin of variable width and depth ( Frisch, 2016: fig. 59).

Tergite IX asymmetrical: left anteroventral side larger, more broadly rounded, and wrapping medially more than right; posterior margin with U-shaped emargination; middorsal base divided medially from anterior to posterior margin of Tergite IX or for most of length but not reaching tergite X. Sternite IX elongate.

Tergite X elliptical; anterior margin rounded and without median point.

Aedeagus (fig. 243) with dorsal surface of median lobe midlongitudinally divided; median lobe darkly pigmented black medially, beginning near base of ventral process and extending posteriorly; parameres present and appressed to surface laterad of median foramen.

FEMALE: Sternite VII unmodified.

Sternite VIII (fig. 242) with posterior margin moderately deeply to shallowly to feebly emarginate to flattened to broadly rounded and not emarginate.

Tergite IX symmetrical: left and right anteroventral sides of approximately equal size; posterior margin with U-shaped emargination; middorsal base fused medially.

Tergite X elliptical; anterior margin broadly rounded and without median point.

DISTRIBUTION AND HABITAT: Hyperscopaeus is speciose and widely distributed in Africa; although with fewer known species, the distribution extends eastward across southern Asia to Australia. The paucity of Asian and Australian species and specimens is an artifact of collecting and doubtless more will be found there. Of the 77 described species included in the genus, 65 are from Africa where they are known from most countries. To now, none have been recorded from Algeria, Botswana, Burundi, Central African Republic, Ethiopia, Libya, Malawi, Mauritania, Morocco, Namibia, Rwanda, South Africa, South Sudan, and Zambia. No species have been reported from Madagascar.

Among the 12 remaining species, three are Sri Lankan, one is from India, another from Bhutan, four from Myanmar, one from Guam, and two are Australian. Unidentified species have been collected from Indonesia (Sumatra, Java), Pakistan, Singapore, Vietnam, and Papua New Guinea (Normanby Island) and, according to Frisch (personal commun.), Malaysia, Thailand, Laos, and Sri Lanka. The two Australian species are from New South Wales, Queensland, and Northern Territory.

Certainly, many more species will be discovered, and the genus will probably be reported from all countries of Africa, Madagascar, and across southern Asia, including China and India, Indonesia, the Philippines, and the island of New Guinea and Australia. Frisch (personal commun.) affirms this opinion.

Little is known of the habitat of species of Hyperscopaeus . Fagel (1973: 50–125) cited label data from species he described or redescribed. He reported some species as having been collected at lights. Others were collected from forest litter or soil in marshy or inundated forest or from sandy shores of rivers. One species, H. convexiceps , was collected from among roots of a species of Cyperaceae in a swampy area ( Fagel, 1973: 125).

Frisch (2012c: 298) reported nothing definitive about the habitat of H. spinosophallatus and said (Frisch, personal commun.) he knows nothing about the habitat of Hyperscopaeus , but thinks it differs from that for Scopaeus . Frisch (personal commun.) found no specimens of Hyperscopaeus in gravel or sandy banks of streams, habitats typical for Scopaeus . In three expeditions to Java and Sulawesi Frisch (personal commun.) found many species and specimens of Scopaeus on riverbanks, but not a single specimen of Hyperscopaeus .

Most of the specimens in the AMNH collection were collected at lights. A couple of specimens from Sri Lanka were found in the bed of a stream.

DISCUSSION: Hyperscopaeus , originally proposed by Coiffait (1984: 150) as a subgenus of Scopaeus for the Egyptian species, Scopaeus spathiferus , is herein raised to generic rank. Only aedeagal characters were originally cited to separate it from other species of Scopaeus ; the absence of a cephalic “fossette” (= trichobothrial cavity), a small, postocular pit, distinguished it from Microscopaeus (= Micranops ). Of note, the trichobothrium was not cited, perhaps overlooked, by Coiffait (1984) for either Scopaeus or Hyperscopaeus .

Eleven years before Coiffait established Hyperscopaeus for one species, Fagel (1973) described or redescribed 126 African species of Scopaeus , which he assigned to 19 species groups. Sixtyone of those species are congeneric with H. spathiferus , the type species of Hyperscopaeus . Fagel assigned those species to four groups: H. gigantulus with one species, H. nitidicollis with 15, H. pseudomentheri with 38 ( Fagel 1973: 49–125), and H. tristis with seven species ( Fagel, 1973: 151–164). Species of those groups are all moved herein to Hyperscopaeus .

Frisch et al. (2002a, 2002b) continued to define this subgenus of Scopaeus by features of the aedeagus, but also wrote that it might be a distinct genus based on many external and sexual apomorphies ( Frisch et al., 2002a: 45). Among the external characters with which Frisch et al. (2002a: 38) defined Hyperscopaeus are the: (1) slender neck (one eighth the width of the head), (2) elongate, parallel-sided head, (3) concave posterior margin of the head, (4) parallel lateral margins of the pronotum, (5) wide protarsomeres (about three times wider than long), (6) emarginate sternite VIII of the female, and (7) more deeply (than for Scopaeus ) emarginate sternite VIII of males. Accentuating details of the aedeagus, Frisch et al. (2002a: 38 and figs. 7–9) further characterized Hyperscopaeus by the: (8) large aedeagus, (9) long, membranous, unipartite apical portion of the median lobe with distinct apical lobes, (10) broad sclerotized ring of the median lobe, and (11) proximal position of the median foramen on the median lobe.

Despite the list of characters published by Frisch et al. (2002a: 38) Hyperscopaeus seemed to me uncertainly defined. Based on aedeagal characters, Hyperscopaeu s appeared to be a monophyletic group, other characters were somewhat nebulous differences of degree. Although the image of the spermatheca ( Frisch et al., 2002a: fig. 23) of Hyperscopaeus is strikingly distinct from the other spermathecae on the same page, no apomorphic feature was pointed to for Hyperscopaeus , on the image or in the text, for distinction from Scopaeus . However, Frisch et al. (2002a: 44) thought the loss of the process of the spermathecal chamber in Hyperscopaeus and its presence in Scopaeus , reflected an apomorphic feature for the latter. Some of the defining characters listed in the previous paragraph faded away as more species were examined; that was particularly true among the Asian species. Frisch, based primarily on aedeagal characters, published—and stated to me in person—that he thought the subgenus Hyperscopaeus should be recognized separately from Scopaeus . When he and I discussed the idea, I was unconvinced that it should be carved from Scopaeus solely based on aedeagal and spermathecal divergences. My misgivings centered on how a genus of more than 400 species might be defined by derived features if the species of Hyperscopaeus were removed. Although, I had no doubt that Hyperscopaeus was a monophyletic group, as are the (other) species groups of Scopaeus , as a matter of practicality, I was (and am) resistant to forcing people to dissect the genitalia just to identify a genus if that group clearly fits within another. Scopaeus with Hyperscopaeus had been defined by the position of paraocular trichobothrium adjacent to the middle of the dorsal margin of the eye, quadridenticulate labral margin, and skinny neck, characters that circumscribed a genus of approximately 450 species from all other Paederinae . Removing Hyperscopaeus from Scopaeus because of autapomorphic characters detected in the former would leave no characters that defined the much larger, remaining cluster of species, Scopaeus . Removing Hyperscopaeus demanded finding derived characters that defined Scopaeus . Without those characters, Hyperscopaeus appeared to be simply a monophyletic group of robust species within Scopaeus .

My opinion was abruptly transformed upon the sudden, surprising discovery of a stridulum in Scopaeus (figs. 105, 106) and its absence in the species now assigned to Hyperscopaeus (figs. 251–253). This new view solidified on finding the pair of long, slender, apically acute metakatepisternal processes in Scopaeus (fig. 97) in contrast to the shorter, apically rounded processes in Hyperscopaeus (fig. 241), and the dorsally sclerotized and fused midlongitudinal strip of the aedeagal median lobe of Scopaeus (fig. 158) in contrast to the membranous median separation for Hyperscopaeus (fig. 243). All these characters are unique and derived for Scopaeus . Unfortunately, Hyperscopaeus , despite its monophyly based on aedeagal features, remains deficient for the presence of external apomorphic features to distinguish it from Scopaeus .

Most of the characters suggested by other investigators or explored herein to define Hyperscopaeus disappear in a fog of variation. Among proposed defining structures are the following.

The slender neck of Hyperscopaeus is one eighth to one sixth as wide as the head and overlaps with some species of Scopaeus that also have a neck a sixth as wide as the head.

The head and prothorax of some species of Hyperscopaeus are each approximately parallel sided, but the lateral sides of others are moderately convergent or broadly and shallowly rounded and akin to species of Scopaeus .

The concave (or emarginate) posterior margin of the head of Hyperscopaeus is found in some species of Scopaeus (fig. 1).

The basal four protarsomes of Hyperscopaeus are three times wider than long according to Frisch et al. (2002a: 38) and might be useful as a defining feature of the genus. However, in the same paper the authors (p. 30) appeared to report overlapping variation of the width of the protarsomeres for some species groups of Scopaeus with the following statement: “In Scopaeus , the protarsomeres are also dilated (chars. 8:2, 8:3) ... in a few species groups.” Characters 8:2 and 8:3 are “about twice as wide as long” and “three times as long as wide” respectively ( Frisch et al., 2002a: 51). However, even if the difference is diagnostic, Frisch and his colleagues did not appear to explore or employ the character further or state the relative width of the protarsomeres of any species groups of Scopaeus . My exploration of the relative length-towidth ratio of Hyperscopaeus and Scopaeus revealed considerable variation, including variation among the basal four tarsomere of individuals. The width of the basal four protarsomeres of Hyperscopaeus varies from about three times the length, to twice the length, to subequal length and width. Similar results were seen for Scopaeus , the protarsomeres varied from somewhat greater than twice as wide as long to twice the length to subequal length and width.

The posterior margin of sternite VIII of Hyperscopaeus females varies from moderately deeply to shallowly to feebly emarginate to straight and without emargination to rounded.

Among suggested aedeagal characters, the position of the median foramen is more proximal, closer to the anterior margin of the median lobe, for Hyperscopaeus in contrast to the more distal position of the median foramen of Scopaeus (cf. Frisch, 2012c: fig. 2, and Frisch et al., 2002a: fig. 20). However, for some species of Scopaeus , for example S. ooderes , the median foramen is quite close to the rounded base of the aedeagus (see Frisch, 2016: fig. 39). This feature may be plesiomorphic for Hyperscopaeus .

Other structures to define Hyperscopaeus and discriminate it from Scopaeus , but that ultimately proved too variable, were explored. Some of these features may be species specific.

The posterior cephalic margin of Hyperscopaeus has a median tumescence that is medially divided by a shallow to moderately deep depression with a black, vertical, median sulcus; the depression is feeble in some species, but a black line or modest sulcus remains. A similar, but feeble, tumescence with depression and sulcus is found in some species of Scopaeus . However, although a possible, but poor, defining feature, it is too inconsistent to be useful.

The posteroventral surface of the head is strongly sloped and broadly concave in many species of Hyperscopaeus , but not all.

Most African species of Hyperscopaeus have a pair of tubercles on the ventral base of the head near each side of the neck (figs. 240, 244, 246); the tubercles of some species are large, in others tiny; the tubercles coalesce to form a short ridge in some; two tubercles are reduced to one in others. Among Asian species the ventrobasal tubercles are small or absent.

The cephalic and pronotal surfaces of most species of Hyperscopaeus are covered with dense, small to minute punctation. For some Asian species the simple cephalic and pronotal punctures are replaced by microtubercles, each with a tiny setate puncture on the peak. Among the named Asian species with setate microtubercles are H. rubrotestaceus and H. semifuscus .

The right mandible of Hyperscopaeus has four denticles; the fourth is separated and distinct from the third in some species, in others it is part of a large, broad, basal lobe with two denticles, a large third and small to tiny fourth; the basal denticulate lobe, although not found in other scopaeine genera, is not found in all species of Hyperscopaeus .

The neck has a shallow to moderately deep nuchal groove adjacent and anterior to the nuchal ridge in some, but not all species of Hyperscopaeus .

A newly discovered structure, of unknown function, is the long, slender, internal apophysis extending posteriorly from the midline of the mesofurcasternum (figs. 241, 250); at least a few species of Hyperscopaeus lack that apophysis and a few species of the Scopaeus chiriquensis species group possess it (fig. 82). Furthermore, use of this potential character will require a dissection that separates the mesothorax from the metathorax or treatment that makes them transparent.

Tergite IX of females of Hyperscopaeus is medially fused basally, but this may be less derived than a divided base.

Among external features that might support the monophyly of Hyperscopaeus are the following.

The gular sutures of Hyperscopaeus are narrowly separated, virtually contiguous in some species, and parallel for most of their length (fig. 244); for most species of Scopaeus the gular sutures are moderately to widely separated but are narrowly separated for species of the S. opacus species group and for some species of the S. chiriquensis species groups.

Some species of Hyperscopaeus , especially the large ones, have a strong ridge on the probasisternum that extends from the anterior, basisternal margin that connects with the intercoxal carina of the probasisternum/profurcasternum. The ridge is present and distinct but shorter and not reaching the intercoxal carina in most species; for at least a few species the ridge appears to be absent. No species of Scopaeus were found with the ridge. However, few species and specimens of Hyperscopaeus were available to me, so this feature might yet be further investigated as diagnostic for Hyperscopaeus and Scopaeus .

Tergite IX of males lacks apodemes on the ventroanterior angle; the posterior margin of sternite VIII of males has a deep, wide, triangular emargination; the aedeagus is large, the median foramen proximal, and the median lobe darkly pigmented, black, beginning at the base of the ventral process and extending posteriorly.

Although, in the present work no external characters unique to Hyperscopaeus were found, perhaps someone else will find an overlooked structure. After all, look at Scopaeus .

On reflection, it is worth noting that despite the energy and time expended in the intense search for unique, external characters to define Scopaeus , the result was to eject Hyperscopaeus as a plesiomorphic group from Scopaeus and to then remember that more than 20 years ago, Frisch et al. (2002a: 38, figs. 40, 41) had hypothesized the Scopaeus subgenus, Hyperscopaeus , to be the sister group of the hundreds of remaining species of Scopaeus .