Description Sphecomyrma

1 description

1.1 s. canadensis
1.2 s. freyi
1.3 s. mesaki
1.4 unplaced specimens

description

drawing of s. freyi worker

sphecomyrma ants can distinguished other ants extremely primitive body structure, small, narrow wasp-like mandibles, short scapes (the basal segment of antenna) , exceptionally long funiculus, 4 times longer scape. suture (a pattern of shallow grooves on head) developed , trochantellus (the proximal end of femur) absent. node (a segment between mesosoma, middle part of body, , gaster) of petiole noticeably dome-shaped , separated propodeum, first abdominal segment, , parts of metasoma, posterior part of body, several constrictions. cuticle (outer exoskeleton of body) not sculptured , covered either scattered or spare setae, different types of bristle or hair-like structures. body structure shows sphecomyrma ants medium-sized formicids. workers known have stingers.

s. canadensis

s. canadensis described holotype , paratype specimen, 1 of canadian amber , other, paratype, poorly preserved , collected medicine hat amber. holotype , paratype specimens, numbered cas 330 , cas 205 respectively, preserved in biosystematics research institute in ottawa, canada. body similar s. freyi, has narrower head s. canadensis (the head of s. freyi 1.00 millimetre (0.039 in) wide). mesosoma more robust , third funicular segment extremely short , long second segment, while twice long in s. freyi. width , length of head same @ 0.66 millimetres (0.026 in) , scapes measure 0.50 millimetres (0.020 in) length of mesosoma varies in holotype , paratype, ranging 1.32 1.57 millimetres (0.052 0.062 in).

s. freyi

drawings of various body parts of s. freyi

s. freyi ants small, measuring 4 millimetres (0.16 in). mandibles wasp-like, 12-segmented antennae far apart each other , second funicular segment longer other segments. unusual ants, such case occurs in nothomyrmecia macrops. scapes short @ 0.57 millimetres (0.022 in). compound eyes long , convex, situated on middle side of head. clypeus (one of sclerites make face of arthropod or insect) broad , convex , ocelli (photoreceptors) developed. mesosoma slender , closely resembles of methocha malayana, measuring 1.48 millimetres (0.058 in). mesonotum long , slender distinct convexed scutum , scutellum, these 2 features separated each other axillary region. spiracles present on metathorax, situated below scutellum. petiole has raised node , separated propodeum , gaster. gaster measures 1.51 millimetres (0.059 in), , acute protruding stinger, measuring 0.33 millimetres (0.013 in) present. legs long , slender 2 tibial spurs present @ each tibia, , tarsal claws have median tooth. 2 worker specimens have little morphological differences, range in size. head , segments of antenna tend smaller in holotype specimen while in paratype larger. pubescence short scattered throughout body, measuring 0.001 millimetres (3.9×10 in). colour of specimens appears light-brown. metapleural gland exhibits notably wide , oval-shaped orifice, (openings body). separation between orifice , posterior portion of propodeum twice diameter orifice itself. cuticle situated in anterior portion (referring in front) of orifice thinner in contrast cuticle surrounding mesosoma, notably transparent. oddly shaped chamber can seen beneath cuticle, atrium (chamber hardened, thickened wall). gland covered in whitish mass , located in anterodorsal region (meaning in front , toward back) of subcuticular chamber. gland said shrunken original size.

s. mesaki

closeup view of s. mesaki

s. mesaki found in small piece of amber barely larger ant itself. incomplete specimen numbered amnh nj-1023 preserved @ american museum of natural history in new york city. appendages breach surface of amber while petiole , gaster absent. engel , grimaldi coined specific epithet after bob mesak, original collector donated specimen museum. species discernible other species portion of clypeus having elongated ventral lobe. broad shallow scrobes of antennae, size of head , oval-shaped eyes can further distinguish s. mesaki other sphecomyrma ants. body parts of ant preserved legs, mesosoma , head. head notably large, shorter mesosoma. head 2.2 mm (0.087 in) long , 1.95 millimetres (0.077 in) wide, eyes alone measuring 0.66 millimetres (0.026 in). vertex covered in sparse pilosity 0.2 millimetres (0.0079 in) setae. ocelli present on top of ants head, precisely located above dorsal tangent. base of antennae emerges scrobes, equally long scape. eyes developed , located above bottom of antennae. clypeus setose, meaning bears bristles or setae, except on middle part. mandibles small , contain 2 teeth. antennae moderately long, scapes short pedicel shorter. mesosoma measures 2.66 millimetres (0.105 in) , setose. several setae seen around metanotum (the dorsal sclerite) , propodeum. coxae, proximal segment , functional base of leg, setose (bearing bristle or setae), inflated , large. metapleural gland opening small , noticeable, located away propodeum , above metacoxa (the hind of coxa). legs moderately long. forelegs first tarsomere (subsegments of tarsus) longer combined length of other tarsomeres more distant first subsegment. number of stiff setae varies on each tarsomere: example, first tarsomere has 7 pairs while fourth tarsomere has 2 pairs. pretarsal claw has single subapical tooth , metasoma absent.

unplaced specimens

s. freyi worker

an additional specimen described possible sphecomyrma male, never assigned specific species. specimen numbered amnh nj-242 collected white oaks outcrop in 1995 , preserved in american museum of natural history. entire body of male specimen preserved. ant genera based on morphology of workers, assigning males species or genus done unless taken colony. however, size, petiole structure, absence of trochantellus , basal antennal structure similar of sphecomyrma worker. small ant, measuring 3.13 millimetres (0.123 in) 3 ocelli present on vertex. stiff hairs can found on frons , vertex. has large eyes , face has 2 pairs of long setae along smaller setae. scape short , around same length flagellomere (one of 3 main segments of antenna); pedicel longer flagellomere 0.3 times, , total length of antenna 2.6 millimetres (0.10 in). of mouthparts covered in bubbles amber, 2 palpals (a pair of appendages found near mouth) seen protruding. mesosoma 1.25 millimetres (0.049 in) in length , petiole 0.35 millimetres (0.014 in), has pairs of long setae on apex of nodus. both tibias have pair of setose , apical spurs on hind tibia pectinate. forewings measure 2.25 millimetres (0.089 in) , hindwings 0.7 times length of forewings. shape of wings consistent other formicids. hindwings have 7 hamuli none found around anterior portions. gaster 1.22 millimetres (0.048 in) long , first , second segments equally long each other (these 2 segments alone cover two-thirds of gaster). terminalia (the last segments of abdomen) difficult examine due layer of froth covering area, there 2 pairs of setose lobes.