Technomyrmex horni Forel, 1912

Yamane, Seiki, Leong, Chi-Man & Lin, Chung-Chi, 2018, Taiwanese species of the ant genus Technomyrmex (Formicidae: Dolichoderinae), Zootaxa 4410 (1), pp. 35-56 : 51-55

Technomyrmex horni Forel, 1912

( FIgS. 13–16 )

Worker diagnosis. TL 2.5–3.5. SCAPE LONg; SI>118 IN MOST SPECIMENS. CLYPEUS WITH LARgE ANTERIOR INCISION; INNER MARgIN OF THIS INCISION MEETINg WITH ANTERIOR CLYPEAL MARgIN IN ROUND bUT DISTINCT ANgLE ( FIg. 13C ). WITH PROPODEUM IN PROFILE, DORSAL FACE STRAIgHT TO SLIgHTLY CONVEX ANTERIORLY, OFTEN WITH WEAK INDENTATION POSTERIORLY; POSTERODORSAL ANgLE ROUND bUT DISTINCT; STRAIgHT-LINE LENgTH OF PROPODEAL DORSUM gREATER THAN LENgTH OF DECLIVITY TO SPIRACLE ( FIg. 13A ). METATHORACIC SPIRACLE FAR FROM METANOTAL gROOVE; DISTANCE bETWEEN THEM AS LONg AS TWO SPIRACLE DIAMETERS OR MORE. HEAD LIgHT bROWN TO bROWN; MESOSOMA SLIgHTLY PALER, OFTEN WITH YELLOWISH TINgE; gASTER DARK bROWN (RARELY WHOLE bODY ALMOST UNIFORMLY LIgHT bROWN); FEMORA AND TIbIAE DARK bROWN WITH APICES WHITISH; MID- AND HIND COXAE MILKY WHITE; TARSI OF ALL LEgS WHITISH TO YELLOWISH.

Worker description. MEASUREMENTS (N=10). TL 2.5–3.5, HW 0.71–0.92, HL 0.77–0.94, SL 0.87–1.10, EW 0.14–0.17, EL 0.18–0.23, PRW 0.46–0.59, MNW 0.26–0.37, CI 86–98, SI 113–130. HEAD ( FIg. 13C ) LONgER THAN bROAD, ALMOST AS LONg AS bROAD IN LARgER SPECIMENS; CI DECREASES WITH INCREASE IN HEAD WIDTH; HEAD IN FULL-FACE VIEW WITH ROUNDLY CONVEX LATERAL MARgIN AND WEAKLY CONCAVE POSTERIOR MARgIN. EYE LARgE, LOCATED IN FRONT OF MIDLENgTH OF HEAD, NOT bREAKINg LATERAL MARgIN OF HEAD WHEN HEAD IS SEEN IN FULL-FACE VIEW (DISTANCE bETWEEN OUTER MARgIN OF EYE AND LATERAL MARgIN OF HEAD TENDS TO bE LONgER IN LARgER SPECIMENS). CLYPEUS POSTERIORLY MARgINED WITH WEAK SUTURE WHICH IS OFTEN INDISTINCT, WITH DEEP AND bROAD ANTERIOR EMARgINATION FORMINg ROUNDLY PRODUCED LATERAL LObES. FRONTAL CARINAE WEAKLY DIVERgINg POSTERIAD, HARDLY ATTAININg LEVEL OF MIDLENgTH OF EYE. MANDIbLE WITH A SERIES OF 10 DISTINCT TEETH, FOLLOWED bY MINUTE DENTICLES ON MASTICATORY MARgIN TOWARD bASAL ANgLE; THIRD TOOTH (COUNTED FROM APEX) DISTINCTLY SMALLER THAN SECOND AND FOURTH. ANTENNAL SCAPE SURPASSINg POSTERIOR MARgIN OF HEAD bY AROUND 2/5 OF ITS LENgTH. PRONOTUM IN DORSAL VIEW DISTINCTLY bROADER THAN LONg, MUCH bROADER THAN MESONOTUM ( FIg. 13B ); MESOPLEURON NOT DEMARCATED FROM MESONOTUM bUT DEMARCATED FROM METAPLEURON bY DEEP SUTURE ( FIg. 13A ); METATHORACIC SPIRACLES LOCATED FAR FROM ANTERIOR MARgIN OF PROPODEUM; DISTANCE bETWEEN THEM AS LONg AS DISTANCE bETWEEN SPIRACLES. PROPODEUM MASSIVE, IN DORSAL VIEW AS bROAD AS MESONOTUM, IN PROFILE ( FIg. 13A ) NOT DEMARCATED FROM METAPLEURON; DORSUM FLAT, OFTEN WITH WEAK INDENTATION IN FRONT OF POSTERODORSAL CORNER THAT IS ROUNDLY ANgLED; STRAIgHT-LINE LENgTH OF DORSUM gREATER THAN LENgTH OF DECLIVITY TO SPIRACLE. GASTRAL TERgITE I DISTINCTLY NARROWED bASALLY, WITH STRAIgHT bASAL MARgIN THAT IS AS LONg AS WIDTH OF PETIOLE.

DORSUM OF HEAD AND MESOSOMA MINUTELY AND DENSELY PUNCTO-RETICULATE. VENTER OF HEAD AND LEgS MORE WEAKLY SCULPTURED AND SLIgHTLY SHINY. ANTENNAL SCAPE MICROSCULPTURED AND DULL. MANDIbLE AND PETIOLE SMOOTH AND SHINY. GASTRAL TERgITES WITH SUPERFICIAL SCULPTURE AND RATHER SHINY.

ENTIRE HEAD EXCLUDINg CLYPEUS AND MOUTHPARTS, AND ENTIRE MESOSOMA EXCEPT ON PROPLEURON WITHOUT STANDINg HAIRS. ANTERIOR MARgINS OF LATERAL LObES OF CLYPEUS EACH WITH TWO LONg AND STRONg HAIRS AND SEVERAL SHORTER AND WEAKER ONES. MANDIbLE WITH DENSE SOMEWHAT APPRESSED HAIRS ON OUTER MARgIN. FEMORA, TIbIAE AND TARSI OF ALL LEgS WITHOUT STANDINg HAIRS; FORE COXA WITH TWO STANDINg HAIRS ON ANTERIOR FACE AND A FEW SHORTER ONES ON POSTERIOR FACE. GASTRAL TERgITE I WITHOUT STANDINg HAIRS; II WITH ONE PAIR, III AND IV EACH WITH TWO PAIRS OF HAIRS; ALL TERgITES WITH DENSE APPRESSED HAIRS THAT ARE SIMILAR TO PUbESCENCE ON HEAD AND MESOSOMA; gASTRAL STERNITES EACH WITH A FEW STANDINg HAIRS.

HEAD, MESOSOMA, FORE COXA AND PETIOLE YELLOWISH bROWN (HEAD SLIgHTLY DARKER). GASTER AND FEMORA AND TIbIAE bROWN TO DARK bROWN. MID- AND HIND COXAE, AND TROCHANTERS, bOTH EXTREMITIES OF FEMORA, AND TARSI OF ALL LEgS WHITISH TO YELLOWISH. (FOR A REDESCRIPTION OF THE SYNTYPES, SEE BOLTON, 2007).

Queen (previously undescribed). MEASUREMENTS (N=2; 1 DEALATE AND 1 ALATE qUEEN). TL 4.5, 5.2; HW 0.97, 0.96; HL 1.01, 0.99; SL 1.00, 1.00; EW 0.25, 0.25; EL 0.32, 0.32; PRW 0.69, 1.04; MSW 0.82, 0.96; CI 96, 97; SI 103, 103. HEAD SHORT, ONLY SLIgHTLY LONgER THAN bROAD, WITH WEAKLY CONVEX SIDES AND VERY SHALLOWLY EMARgINATE POSTERIOR MARgIN ( FIg. 14C ). CLYPEUS ANTERIORLY WITH bROAD, MODERATELY DEEP MEDIAN CONCAVITY; LATERAL LObES LARgE WITH ROUND ANTERIOR MARgINS; CLYPEUS POSTERIORLY MARgINED bY SUTURE. EYE LARgE, ALMOST REACHINg LATERAL OUTLINE OF HEAD OR WEAKLY bREAKINg THE LATTER. DISTANCE bETWEEN POSTERIOR OCELLI MUCH LONgER THAN THAT bETWEEN POSTERIOR OCELLUS AND ANTERIOR OCELLUS. SCAPE SURPASSINg POSTERIOR MARgIN OF HEAD bY ITS 2/5 LENgTH ( FIg. 14C ). WITH MESOSOMA IN PROFILE ( FIg. 14A ), MESOSCUTUM LARgE COMPOSED OF ANTERIOR SLOPE AND POSTERIOR FLAT PORTION; SEEN FROM AbOVE, MESOSCUTELLUM ROUND, SLIgHTLY bROADER THAN LONg ( FIg. 14B ); MESOPLEURON DIVIDED INTO TWO PARTS bY A DISTINCT SUTURE; ANEPISTERNUM DISTINCTLY MARgINED WITH CARINA. METANOTUM VERY SHORT (jUST A NARROW bAND); METAPLEURON NOT DEMARCATED FROM PROPODEAL SIDE bY SUTURE. PROPODEUM WITH SHORT DORSUM AND FLAT DECLIVITY, WITH PAIR OF LOW TUbERCLES bETWEEN DORSUM AND DECLIVITY; STRAIgHT-LINE LENgTH OF PROPODEAL DORSUM SHORTER THAN LENgTH OF DECLIVITY TO SPIRACLE; PROPODEAL SPIRACLE LOCATED ON SIDE OF PROPODEUM, VERY CLOSE TO ITS POSTERIOR MARgIN.

ALMOST ENTIRE bODY VERY FINELY AND DENSELY PUNCTATE AND MAT; MANDIbLE, MSOSCUTELLUM AND gASTER MORE SHINY; PETIOLE NEARLY IMPUNCTATE AND SHINY. PILOSITY AND COLORATION ALMOST THE SAME AS IN THE WORKER.

Distribution. BORNEO, KRAKATAUS, SINgAPORE, MALAY PEN., INDIA, SRI LANKA, THAILAND, CHINA, TAIWAN.

Specimens examined ( MNMS, SKYC, TFRI). CHIAYI COUNTY: 6 WORKERS & 1 FOUDRESS qUEEN, ALISHAN, SHUISHELIAO (CA. 1,200 M ALT.), 3.VII.2017 , NEST IN DEAD bAMbOO, SK. YAMANE LEg. (TW17-SKY-13); 2 WORKERS, SAME LOC. AND DATE, SK. YAMANE. LEg. NANTOU COUNTY: 2 WORKERS, NANSHANCHI, 22.VIII. 1 987, M. TERAYAMA LEg.; 2 WORKERS, HUISUN EXP . FOREST (500–800 M ALT.), 24.0896°N, 121.0305°E, 27–30.IV.2017, SECONDARY FOREST, C. M. LEONg LEg.; 7 WORKERS, ENVIRONS OF PULI, SHIKENg ROAD, 23.9964°N, 121.0055°E, 6.VII.2017, NEST UNDER STONE, SK. YAMANE LEg. (TW17-SKY-63). TAIPEI COUNTY: 1 WORKER, ULAI, FUSHAN, 20. IV.2010 , ON Mallotus LEAF, SK. YAMANE LEg.; 7 WORKERS, SAME LOC. AND DATE, NEST IN DEAD bAMbOO STEM, SK. YAMANE LEg. (TW10-SKY-05). TAITUNg COUNTY: 16 WORKERS & 2 WINgED qUEENS, TUNgHA (660 M ALT.), 24. IV.2010 , NEST IN CREVICE OF ROCK, SK. YAMANE LEg. (TW10-SKY-14); 7 WORKERS, DULANSHAN (650 M ALT.), 24.IV.2010, LOWER VEgETATION, SK. YAMANE LEg.

Remarks. BOLTON (2007) NOTED THAT IN T. horni , WITH THE PROPODEUM IN PROFILE THE DORSUM IS FLAT TO SHALLOWLY CONVEX, bUT DID NOT MENTION THE WEAK IMPRESSION jUST IN FRONT OF THE ANgLE bETWEEN THE DORSUM AND DECLIVITY. THIS IMPRESSION IS VERY OFTEN SEEN IN THE SPECIMENS LISTED AbOVE. THE SPECIMENS FROM HIgHER ELEVATIONS ARE DARKER IN bODY COLOUR THAN IN THOSE FROM LOWER ELEVATIONS IN bOTH WORKERS AND qUEENS. THE VARIATION IN bODY PROPORTION IN WORKERS IS MUCH MORE PRONOUNCED IN THIS SPECIES THAN IN THE RELATED TAIWANESE SPECIES, T. formosensis sp. nov. (SEE CI AND SI FOR bOTH SPECIES). IN THE MEASUREMENTS THE TWO qUEENS (ORIgINATED FROM DIFFERENT COLONIES) ARE ALMOST IDENTICAL EXCEPT IN THE VALUES FOR THE PRONOTAL WIDTH AND MESONOTAL WIDTH; THIS MAY bE bECAUSE IN THE DEALATE qUEEN THE THORAX SHRINKS AFTER SHEDDINg THE WINgS. THE CELL dc1 OF THE FOREWINg IS PRESENT IN T. horni ( FIg. 15A ), bUT AbSENT IN T. brunnus AS THE VEIN 1m-cu IS AbSENT.

Figures

FIGURE 13. Technomyrmex horni worker (LCM00066). A, habitus in profile, B, ditto in dorsal view & C, head in full-face view.

FIGURE 14. T.horni queen (LCM00065).A, habitus in profile, B, ditto in dorsal view &C, head in full-face view.

FIGURE 15. T.horni queen (LCM00065).A, fore wing & B,hind wing.