Agathidium exiguum, Melsheimer, 1844

MILLER, KELLY B. & WHEELER, QUENTIN D., 2005, Slime-Mold Beetles Of The Genus Agathidium Panzer In North And Central America, Part Ii. Coleoptera: Leiodidae, Bulletin of the American Museum of Natural History 2005 (291), pp. 1-167: 75-85

publication ID

http://doi.org/ 10.1206/0003-0090(2005)291<0001:SBOTGA>2.0.CO;2

persistent identifier

http://treatment.plazi.org/id/038387B3-3707-B950-FFE3-5094FB1F0C76

treatment provided by

Felipe

scientific name

Agathidium exiguum
status

 

exiguum   . 172, A. fawcettae   . Bars = 0.5 mm.

pointed (fig. 124); apical portion of median lobe of aedeagus relatively broad (fig. 193)................................. A. hidalgoense   , new species

10(7). Anterior margin of mesosternum deeply emarginate on each side of midline (fig. 114)... A. skoliosternum   , new species

— Anterior margin of mesosternum not deeply emarginate on each side of midline ............................. 11

11(10). Head and pronotum red, elytra black; eyes relatively large and finely faceted; male metafemoral tooth small, anteapical (fig. 126); median lobe of aedeagus in lateral aspect slender and strongly curved medially, strongly expanded along dorsal and ventral margins at base of apical portion (fig. 200)........... A. erythromelas   , new species

— Head and pronotum concolorous brown to piceous; eyes various, male metafemoral tooth, and median lobe of aedeagus various.................. 12

12(11). With prominent flat, triangular process extending anteriorly from labium; dorsal surfaces with distinct microreticulation between punctures consisting of small, isodiametric cells................ A. rhamphastes   , new species

— Without process extending from labium; dorsal surfaces without microreticulation, smooth between punctures.. 13

13(12). Median lobe of aedeagus with lateral and dorsal carinae and sulcus for reception of lateral lobes weakly developed, indistinct...................... 14

— Median lobe of aedeagus with lateral and dorsal carinae and sulcus for reception of lateral lobes strongly developed, carinae prominently protruding dorsally and/or laterally............... 20

14(13). Size very large (TBL> 4.0 mm); median lobe of aedeagus long, relatively straight, apical portion short, apically rounded (fig. 207), operculum extending to apex of median lobe of aedeagus, with two lateral teeth on each side of apex (fig. 207).................... A. megoniscoides   , new species

— Size smaller (TBL <4.0 mm); median lobe of aedeagus not so long and straight, apical portion longer, lateral sulcus more strongly developed, operculum generally not extending to apex of median lobe of aedeagus..... 15

15(14). With prominent tumidity or prominence on gula..................... 16

— With gula unmodified............ 18

16(15). Male metafemoral tooth large and acutely pointed (fig. 129); gula with prominent medial tumidity; apex of median lobe of aedeagus in lateral aspect with apex gently curved (fig. 211).................... A. grumum   , new species

— Male metafemoral tooth smaller, less prominent; gula with prominent tumidity near anterior margin; apex of median lobe of aedeagus in lateral aspect with apex abruptly hooked...... 17

17(16). Operculum of median lobe of aedeagus relatively slender, subapically narrowed (fig. 213)...................... A. triangularum   , new species

— Operculum of median lobe of aedeagus relatively broadly rounded, margins evenly curved to apex (fig. 216)........... A. lobosternum   , new species

18(15). Operculum of median lobe of aedeagus apically laterally expanded with lateral teeth (fig. 219)............................ A. potosii   , new species

— Operculum of median lobe of aedeagus not apically laterally expanded with teeth........................ 19

19(18). Male metafemoral tooth located about two­thirds distance from base of metafemur (fig. 133); apex of operculum of median lobe of aedeagus rounded, very slightly emarginate (fig. 222)........ A. popocatepetlae   , new species

— Male metafemoral tooth located subapically (fig. 134); apex of operculum of median lobe of aedeagus more strongly emarginate (fig. 225).......................... A. hyle   , new species

20(13). Eyes very strongly dorsoventrally compressed to long, slender lines (fig. 109); median lobe of aedeagus distinctly recurved in lateral aspect (fig. 230)............. A. stenomma   , new species

— Eyes variously reduced, but not so strongly compressed to long, slender lines; median lobe of aedeagus recurved or not in lateral aspect... 21

21(20). Male protrochanter with distinct, prolonged, slender, flattened spine (fig. 115); metatrochanter concave with apex produced ventrally as short, prominent tubercle; median lobe of aedeagus with apical portion long and sharply recurved in lateral aspect, slightly bent, twisted, and asymmetrical (figs. 232, 233)...................... A. tribulosum   , new species

— Male protrochanter without a spine; metatrochanter not concave or with apex produced; median lobe of aedeagus various in shape, but with apex symmetrical..................... 22

22(21). Male procoxa produced into a very broad, flat, ventral tooth (fig. 116); male metafemur with two moderatesized teeth along posterior margin with broad, concave margin between them (fig. 137).......................... A. tribulograndum   , new species

— Male procoxa unmodified, not produced; male metafemur with teeth various, but not configured into two teeth with concave area between............. 23

23(22). Male with prominent series of four denticles on posterior margin of metafemur with largest about two­thirds distance from base of metafemur (fig. 138); operculum of median lobe of aedeagus long and broad, apically distinctly emarginate with each ramus apically expanded ventrad (fig. 240)............ A. invisitatum   , new species

— Male with only a single metafemoral tooth or with multiple very small teeth; operculum of median lobe of aedeagus various...................... 24

24(23). Male with posterior margin of metafemur with series of small but distinctive teeth (fig. 139); median lobe of aedeagus with apical portion very slender in ventral aspect, operculum long, slender, and apically with prominent lateral hooks (fig. 244)...................... A. multidentatum   , new species

— Male with posterior margin of metafemur without series of teeth, although margin has minute serrations in some species; median lobe of aedeagus not slen­ der in ventral aspect and without long operculum bearing lateral hooks.. 25

25(24). Male metafemoral tooth very large, length greater than width, apex acutely pointed...................... 26

— Male metafemoral tooth various, but not very large, length not greater than width and with apex acutely pointed ............................ 27

26(25). Size larger (TBL> 2.5 mm); mesosternal carina of most specimens with low, medial notch; median lobe of aedeagus with prominent, dorsal, lobelike carina with a large fovea along it into which fits the lateral lobes (figs. 248, 249)........... A. sejunctum   , new species

— Size smaller (TBL <2.5 mm); specimens without medial notch in mesosternal carina; median lobe of aedeagus with dorsal carina and fovea less well developed (figs. 251, 252)........... A. grandidentatum   , new species

27(25). Operculum of median lobe of aedeagus extending to apex of median lobe, operculum and apical portion of median lobe similar in shape, each apically similarly truncate (figs. 254, 255)......... A. andersoni   , new species

— Operculum of median lobe of aedeagus in most species not extending to apex of median lobe, operculum and median lobe different in shape and not both apically similarly truncate....... 28

28(27). Operculum of median lobe of aedeagus distinctly T­shaped with apicolateral, pointed projections (fig. 257); median lobe in lateral aspect with apex recurved (fig. 259)........................ A. disgregum   , new species

— Operculum of median lobe of aedeagus not T­shaped; median lobe in lateral aspect various.................. 29

29(28). Median lobe of aedeagus in lateral aspect short, strongly curved, strongly expanded medially due to dorsal production of dorsomedial carina, with very large lateral fovea for reception of lateral lobe (fig. 262); male metafemoral tooth moderately large, anteapical and with series of smaller serrations along posterior margin of metafemur (fig. 144).... A. oaxacaense   , new species

— Median lobe of aedeagus in lateral aspect longer, not so strongly curved, not as strongly expanded medially; male metafemoral tooth various, some species with series of smaller serrations.. 30

median lobe, lateral; 221, left lateral lobe, lateral. 222–224, A. popocatepetlae   : 222, ventral; 223, median lobe, lateral; 224, left lateral lobe, lateral. 225–227, A. hyle   : 225, ventral; 226, median lobe, lateral; 227, left lateral lobe, lateral. 228–231, A. stenomma   : 228, ventral; 229, median lobe, apex, ventral; 230, median lobe, lateral; 231, left lateral lobe, lateral.

30(29). Apex of median lobe of aedeagus distinctly recurved in lateral aspect, apically pointed and abruptly hooked ventrad........................ 31

— Apex of median lobe of aedeagus not distinctly recurved in lateral aspect, apically straight or evenly curved and in some species angled dorsad or ventrad ............................ 32

31(30). Operculum of median lobe of aedeagus short, narrow basally, apically relatively broadly expanded and emarginate with each ramus broad and apically pointed (fig. 264); eyes prominent and multifaceted (fig. 108)...................... A. oculeum   , new species

— Operculum of median lobe of aedeagus long, relatively slender, apex emarginate with each ramus narrowly rounded apically (fig. 267); eyes dorsoventrally compressed, reduced..................... A. recurvatum   , new species

32(31). Operculum of median lobe of aedeagus relatively short and broad, length about 2× greatest width............. 33

— Operculum of male long and slender, about 2.5–4× greatest width..... 35

33(32). Size large (TBL> 4.0 mm); apical portion of median lobe of aedeagus expanded medially along ventral margin in lateral aspect (fig. 272)................. A. impensum   , new species

— Size smaller (TBL <4.0 mm); apical portion of median lobe of aedeagus not expanded in lateral aspect....... 34

34(33). Apex of median lobe of aedeagus in lateral aspect slender, curved slightly dorsad, apex narrowly rounded (fig. 275)........... A. cheneyi   , new species

— Apex of median lobe of aedeagus in lateral aspect broad, not curved dorsad, apex broadly rounded (fig. 278)............ A. tenangoense   , new species

35(32). Apex of operculum of median lobe of aedeagus in ventral aspect with apex laterally flared into relatively prominent, pointed processes............. 36

— Apex of operculum of median lobe of aedeagus in ventral aspect with apex with lateral margins not flared or produced ............................ 37

36(35). Apex of median lobe of aedeagus in lateral aspect distinctly expanded medially along ventral margin (fig. 282); operculum in lateral aspect apically curved ventrad, expanded apically (fig. 282)..... A. rumsfeldi   , new species

— Apex of median lobe of aedeagus in lateral aspect evenly narrowed to pointed apex (fig. 286); operculum in lateral aspect straight to narrowly rounded apex (fig. 286).. A. hirsutum   , new species

37(35). Apex of operculum of median lobe of aedeagus in lateral aspect broad and hooked dorsad (fig. 290); apex of median lobe in ventral aspect very narrow, straight, apically very narrowly round­ ed (fig. 289).............................. A. cortezi   , new species

— Apex of operculum of median lobe of aedeagus in lateral aspect apically not broad, not hooked dorsad; apex of median lobe in ventral aspect not as strongly narrowed, apically broadly rounded..................... 38

38(37). Gula medially with a broad, prominent tumidity.............................. A. tumidiventre   , new species

— Gula unmodified................ 39

39(38). Apical portion of median lobe of aedeagus in lateral aspect expanded along ventral margin (fig. 297); operculum of median lobe shorter and slightly broad­ er, ending distinctly short of apex of median lobe (fig. 296)........................ A. aztec   , new species

— Apical portion of median lobe of aedeagus in lateral aspect not expanded along ventral margin (fig. 301); operculum of median lobe longer and more slender, extending nearly to apex of median lobe (fig. 299).................... A. iridescens   , new species

40(3) ( A. dentigerum   subgroup). Gula with small but prominent medial lobe on gula........................ 41

— Gula unmodified, without medial lobe.. ............................ 43

apex, ventral; 246, median lobe, lateral; 247, left lateral lobe, lateral. 248–250, A. sejunctum   : 248, ventral; 249, median lobe, lateral; 250, left lateral lobe, lateral. 251–253, A. grandidentatum   : 251, ventral; 252, median lobe, lateral; 253, left lateral lobe, lateral. 254–256, A. andersoni   : 254, ventral; 255, median lobe, lateral; 256, left lateral lobe, lateral. 257–260, A. disgregum   : 257, ventral; 258, median lobe, apex, ventral; 259, median lobe, lateral; 260, left lateral lobe, lateral.

41(40). Apical portion of median lobe of aedeagus strongly and broadly sinuate in lateral aspect (fig. 305)........................... A. dentigerum Horn  

— Apical portion of median lobe of aedeagus straight or with only apex of median lobe abruptly sinuate in lateral aspect........................ 42

42(41). Apical portion of median lobe of aedeagus straight to apex in lateral aspect (fig. 308).. A. stephani   , new species

— Apical portion of median lobe of aedeagus with apex abruptly sinuate in lateral aspect (fig. 310).................... A. akrogeneios   , new species

43(42). Posteromedial margin of male metacoxa with broad, rounded, prominent lobe (fig. 117); apical portion of median lobe of aedeagus in lateral aspect strongly curved dorsad (fig. 312), in ventral aspect with apex distinctly arrowhead­shaped (fig. 311)................... A. framea   , new species

— Posteromedial margin of male metacoxa not modified; apical portion of median lobe of aedeagus variously curved or straight in lateral aspect, in ventral aspect not arrowhead­shaped...... 44

44(43). Size very small (TBL <2.2 mm); median lobe of aedeagus with operculum very short, with rami straight and not apically expanded (figs. 314, 317)... ............................ 45

— Size larger (TBL> 2.2 mm); median lobe of aedeagus with operculum longer, rami of some species apically expanded...................... 46

45(44). Apex of median lobe of aedeagus curved dorsad in lateral aspect (fig. 315), in ventral aspect apically truncate (fig. 314).. A. appalachium   , new species

— Apex of median lobe of aedeagus straight in lateral aspect (fig. 318), in ventral aspect apically pointed (fig. 317).......... A. pocahontasae   , new species

46(44). Apical portion of median lobe of aedeagus in lateral aspect strongly curved dorsad (fig. 321), in ventral aspect slen­ der and evenly tapered to narrowly rounded apex (fig. 320).................. A. carolinense   , new species

— Apical portion of median lobe of aedeagus in lateral aspect not strongly curved dorsad, in ventral aspect various, generally somewhat expanded medially, but not evenly tapered to narrowly rounded apex........... 47

47(46). Median lobe of aedeagus in lateral aspect distinctly bent ventrad at base of apical portion (fig. 324).......................... A. gallititillo   , new species

— Median lobe of aedeagus in lateral aspect only slightly or not bent ventrad at base of apical portion.............. 48

48(47). Apical portion of median lobe of aedeagus abruptly narrowed near base, lateral margins subparallel thereafter (fig. 326); rami of operculum apically expanded, rounded, and divergent, extending nearly to apex of median lobe (fig. 326)............................. A. divaricatum   , new species

— Apical portion of median lobe of aedeagus not abruptly narrowed near base in ventral aspect, lateral margins evenly convergent or slightly constricted basally, operculum not apically expand­ ed, rounded, or divergent, not extending nearly to apex of median lobe... ............................ 49

49(48). Apical portion of median lobe of aedeagus with margins evenly convergent to apex (fig. 329), in lateral aspect straight to apex (fig. 330)........................... A. bushi   , new species

— Apical portion of median lobe of aedeagus distinctly constricted near base (fig. 332), in lateral aspect distinctly curved dorsad at apex (fig. 333)................. A. georgiaense   , new species

50(4) ( A. microphthalmum   subgroup). Eyes ovoid, dorsally directed (fig. 110); median lobe of aedeagus stout, apically abruptly curved and sharply pointed in ventral aspect (fig. 335)................ A. chauliodoum   , new species

— Eyes shaped like elongate triangles, more laterally directed (figs. 111, 112); median lobe of aedeagus various... 51

51(50). Median lobe of aedeagus with apex abruptly expanded and truncate (fig. 338)............................. A. microphthalmum   , new species

— Median lobe of aedeagus with apex pointed, not expanded (fig. 341)............. A. nimbosilva   , new species

52(4) ( A. oniscoides   subgroup). Median lobe of aedeagus with operculum long, slender, evenly tapered, with apex laterally expanded...................... 53

— Median lobe of aedeagus with operculum shorter and broader, apex not expanded in most species............... 54

53(52). Size generally larger (TBL = 2.5–5.0 mm); dorsal surfaces black; metasternal fovea moderately large and conspicuous.......................... A. oniscoides Palisot de Beauvois  

— Size smaller (TBL = 2.2–2.9 mm); dorsal surfaces red; metasternal fovea minute, inconspicuous............................... A. rubellum Fall  

54(52). Lateral lobe with apical portion directed at angle dorsad in lateral aspect with subapical expansion on dorsal margin (fig. 352)... A. exiguum Melsheimer  

— Lateral lobe with apical portion various but without subapical dorsal expansion in lateral aspect (fig. 355)................. A. fawcettae   , new species

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Leiodidae

Genus

Agathidium