Latrodectans
hasselti Anhang
[Marks
Bronwyn/Julia Twohig]
Description
of Latrodectus hasseltii
The spider
belongs to the phylum Arthropoda, the order of Araneae and the family of
Theridiidae.
The female
Latrodectus hasseltii is approximately 6 - 11mm long with a characteristically
globular satin black abdomen which bears on the dorsal aspect a bright red or
orange longitudinal stripe. The coloured marking may
vary in
shape and can be fragmented. The markings can also be, although deemed rare,
coloured pink or light grey. The ventral abdomen depicts a red hourglass
marking. The abdomen is large compared to the cephalothorax.
The legs
are thin and long. Ventrally and distally on tarsus IV is a "comb"
consisting of serrated bristles used for combing out silk from the spinnerets
to wrap the prey.
The male
redback is rarely seen. It is approximately one third of the size of a
fullgrown female, the abdomen is oblong rather than spherical and the
colourings are creamy brown to brown. The characteristic stripe is paler
than that
exhibited by the female. The male is considered relatively harmless.
Habitat and
distribution
Latrodectus
hasseltii is primarily a ground dwelling, web building spider. They prefer
dark, dry places, storage areas and outbuildings rather than permanently occupied
rooms. Redback spiders arc commonly found near
human
habitation: under houses, in boxes, including letter and pas boxes, sheds und
around metallic objects such as tins and machinery. When outdoor toilets are
common in Australia, the redback would frequently he seen
there. In
the bush they are found in logs, under hark or rocks, and in foliage of dense shrubs.
The spider is distributed widely throughout Australia with the denser populations
being found in the warmer areas.
Lat-h. has
been identified in a wide range of climatic conditions with lempcraturcs
ranging from freezing to 41°C.
The web
The
irregular and untidy web of the redback generally consists of three parts; a retreat,
a trap section, and an array of several strands that act as trap threads. Any
contact with the sticky trap threads signals the spider to come
out of its retreat.
The prey is swathed with extremely strong silk which effectively immobilises
it. Once the prey has been restrained it is bitten and taken back to the retreat
where it is ingested.
The spider
has a varied diet with beetles and insects being most common, but other larger
and heavier animals including lizards, snakes and mice, have fallen prey to the
redback.
Reproduction
The male
presence in the web generally goes unnoticed by the female, as she is unresponsive
to prey less or equal in weight to that of the male spider. The courtship of L.
hasseltii is activated by web pheremones. To alert the female of his presence
the male performs many acts including abseiling, leg waving, web cutting and
web bouncing. This performance may continue for many hours and is considered to
be physiological priming for the female.
When the
female adopts the mating posture, the male climbs onto the ventral aspect of
her abdomen and continues pre-copulatory foreplay by stimulating the epigynum
(female reproductive opening) with his palps.
The embolus
(male reproductive organ) is then inserted into the epigynal duct. Immediately
after insertion the male raises himself into a headstand position and somersaults
towards the female's sternum. She secures his
abdomen
with her fangs and exudes digestive fluids onto her mate. This behaviour is
unique to L. hasseltii and is not seen in any other Latrodectus species.
The female
eventually releases the male, 5 to 20 minutes later, however he returns in
approximately 10 - 15 minutes and performs a 2nd insemination. The somersault
is also performed again. At this point the female then
begins to
ingest her mate. This sexual cannibalism is seen in relatively few other
species.
The female
may lay as many as six egg sacs each containing up to 300 eggs. The sacs are
spherical and are approximately 10mm in diameter and are usually suspended in
the spider's retreat. Neonatal spiderlings disperse by "ballooning",
an aerial mode of transport which utilises silk.
Young
spiderlings are highly cannibalistic and the mother may also devour some of her
offspring. Cannibalism seems to be a growth strategy for the female, from the
neonatal stage to adulthood the cannibalistic female
grows
quickly and in this competitive environment they prey on smaller siblings.
The female
L. hasseltii is not aggressive unless she is protecting her young, or otherwise
threatened. Usually she will feign death if disturbed.
Frei nach: A. Richter:
Tiefe Sehnsucht nach Zuhause/kommen nie an/unerreichbare Wünsche
Verlangt Gemeinschaft (nicht Ehemann)
alter Kummer über Verlassen sein durch Eltern
trauern: alte Wunden öffnen sich/heilen nicht (kein Trost)
Gedanken kreisen um Beziehung
(Kopfschmerz tief in Augen)
tiefe Angst/bedroht: (nachts)/alleine sein/Zukunft/verfolgt sein/eigene Gesundheit (panische Angst)
Reizbar/Wut/Abgeneigt: Beziehung/Familie/Partner/Berührung
abwertende Beziehung: zu anderen/zu sich selbst
Selbstvorwürfe - sehr kritisch zu anderen
Traum von Selbstverletzung
will harten Druck
fühlt sich hässlich/schmutzig
Pickel/Ulcera im Gesicht
1. Sinne alarmiert: Geräusche/Geschmack
Schmerz
Genitale (Clitoris/Glans)
2. Gehetztes kurzes Agieren/wirft im Ärger mit Gegenstände/wildes Tanzen
kurzer Schlaf/schlaflos
springt aus Bett
ängstliche Ruhelosigkeit (Inneres Kribbeln: Rücken/Zähne/Larynx/Genitale/Arme/Haut)
innen erregt/schnelle Stimmungswechsel
kurz vor dem Sprung - auf und weg
Kitzelhusten, heftiges Niesen und Nase läuft massiv (Pollinosis)
häufiges/unwillkürliches Wasser lassen
fleißig, klarer Geist, fast hellsichtig
„Heiß werden“
3. Schmerzende Mitte (stechende Schmerz in Brustkorb/Herz)
Druck u. Schwellung der Drosselgrube (= Kuhle über Sternum)/“Wie Kloß“ in Schilddrüse
wunder Schmerz der Brüste/wunder Nacken/Schulter/Rücken
tiefer Nierenschmerz („es geht an die Nieren“)
Gestaut/voller Wünsche/überfüllt von Gedanken
Schwellung lokal
voll, schwer, dumpf, drückend/schmerzend
Kopf, Occiput - Rücken/Kehle/Brustkorb/Brüste/Sternum/Uterus/Beine
verstopfte Nase, blockierte Menses
Gesicht pulsierend gebläht
Steif - schmerzend Nacken/Lendenwirbelsäule
4. ?
5. Verzettelt: fruchtlose Aktivität/ungeschickt – stolpern/läuft gegen Gegenstände, knickt um
Zeit vergeht zu langsam
Kopf und Körper tun Verschiedenes
Indifferenz für Essen
abgelenkt, vergisst einzupacken
Konfusion/Fehler:
Schreiben, Sprechen, Rechnen, Zeit
lesen schwierig
müde Augen
Ohrgeräusche
6. Kalt ausgelaugt
will nicht aufstehen, lethargisch/verlangsamt/nicht zusammenhängend
Kälte: Abneigung sich aufzudecken
Ohnmacht - Übelkeit mit Hunger und auch Appetitlosigkeit
Kaltes schmerzt
ohne Selbstgefühl/-bewusstsein
taube Arme/Hände/Füße/Kopf
will eigenen Raum - „Detached“
weit entfernt gefühlt
tiefe Verlassenheit - isoliert