Miagrammopes is a genus of cribellate orb weavers first described by Octavius Pickard-Cambridge in 1870. These spiders have a unique shape and only four of their original eight eyes. They spin a single line of web, actively watching and jerking the line to catch their prey.

Life style

Miagrammopes species construct a horizontal, usually single thread between two branches or twigs. The spider lays down a thick band of viscid silk and then takes up a position upside down near a point of attachment, with only the central section consisting of cribellate silk. The thread has one or a few sticky capture threads attached to it that are held under tension. The line is kept under tension and released with a snap when prey alights on the inviting line and becomes entangled.

The attack behaviour involves rapid jerking and sudden sagging of the capture thread. In some tropical species such as Miagrammopes brevicaudus, the web consists of three threads. The spider positions itself at the end of one of the upper threads and only approaches the mid-section in darkness.

The female carries the cylindrical egg-sac until the spiderlings emerge.

Description

The carapace is longer than wide, low, and weakly convex above. The cephalic region is broad and obtusely rounded in front. The thoracic region has nearly subparallel sides and is truncated behind.

The eyes are unequal in size and arranged in two unequal transverse rows. The eyes of the front row are minute or obsolete, with evidence of anterior median eyes seen in small, dark pigment spots in some specimens. The posterior row is recurved with median eyes widely separated. The clypeus is broad and sloping, equal in width to two or more diameters of the posterior median eye.

The sternum is elongated and divided into two unequal sternites seemingly joined to the carapace between second and third coxae by narrow sclerites. The abdomen is elongated, often tubular. The calamistrum is a broad lobe with the spinning field entire.

The leg formula is 1423. The legs are quite long and unequal, with the second and third pairs short and thin. The fourth pair is long and laterally compressed, while the first pair is stoutest and longest with apical segments laterally compressed. The trochanters of the first and fourth legs are strongly developed, exceeding the coxae in length. The metatarsus IV is laterally compressed with a ventral comb of short spines. The calamistrum occupies most of the length of the compressed fourth metatarsus and consists of a single, sinuous series of curved bristles set on a thin keel on the dorsal surface of the segment. The front tibiae of males often have rows of stout spines.

Species

, this genus includes 71 species:

Miagrammopes albocinctus Simon, 1893 – Venezuela Miagrammopes alboguttatus F. O. Pickard-Cambridge, 1902 – Guatemala to Panama Miagrammopes albomaculatus Thorell, 1891 – India (Nicobar Is.) Miagrammopes animotus Chickering, 1968 – Puerto Rico Miagrammopes apostrophus Sen, Saha & Raychaudhuri, 2013 – India Miagrammopes aspinatus Chickering, 1968 – Panama Miagrammopes auriculatus Cai & Xu, 2021 – China Miagrammopes auriventer Schenkel, 1953 – Venezuela Miagrammopes bambusicola Simon, 1893 – Venezuela Miagrammopes bifurcatus Dong, Yan, Zhu & Song, 2004 – China Miagrammopes birabeni Mello-Leitão, 1945 – Argentina Miagrammopes biroi Kulczyński, 1908 – Papua New Guinea Miagrammopes bradleyi O. Pickard-Cambridge, 1874 – Australia (New South Wales) Miagrammopes brasiliensis Roewer, 1951 – Brazil Miagrammopes brevicaudus O. Pickard-Cambridge, 1882 – South Africa, Eswatini Miagrammopes brevior Kulczyński, 1908 – Papua New Guinea Miagrammopes brooksptensis Barrion & Litsinger, 1995 – Philippines Miagrammopes cambridgei Thorell, 1887 – Myanmar, Indonesia (Sumatra) Miagrammopes caudatus Keyserling, 1890 – Australia (Queensland) Miagrammopes ciliatus Petrunkevitch, 1926 – Puerto Rico, St. Vincent Miagrammopes constrictus Purcell, 1904 – South Africa Miagrammopes corticeus Simon, 1893 – Venezuela Miagrammopes cubanus Banks, 1909 – Cuba Miagrammopes extensus Simon, 1889 – India Miagrammopes fasciatus Rainbow, 1916 – Australia (Queensland) Miagrammopes ferdinandi O. Pickard-Cambridge, 1870 – Sri Lanka Miagrammopes flavus (Wunderlich, 1976) – Australia (Queensland) Miagrammopes gravelyi Tikader, 1971 – India Miagrammopes grodnitskyi Logunov, 2018 – Vietnam Miagrammopes gulliveri Butler, 1876 – Mauritius (Rodriguez) Miagrammopes guttatus Mello-Leitão, 1937 – Brazil, Argentina Miagrammopes indicus Tikader, 1971 – India Miagrammopes intempus Chickering, 1968 – Panama Miagrammopes kinabalu Logunov, 2018 – Malaysia (Borneo) Miagrammopes kirkeensis Tikader, 1971 – India Miagrammopes larundus Chickering, 1968 – Panama Miagrammopes latens Bryant, 1936 – Cuba, Hispaniola Miagrammopes lehtineni (Wunderlich, 1976) – Australia (Queensland) Miagrammopes licinus Chickering, 1968 – Panama Miagrammopes longicauda O. Pickard-Cambridge, 1882 – South Africa Miagrammopes luederwaldti Mello-Leitão, 1925 – Brazil Miagrammopes maigsieus Barrion & Litsinger, 1995 – Philippines Miagrammopes mexicanus O. Pickard-Cambridge, 1893 – United States, Mexico Miagrammopes molitus Chickering, 1968 – Jamaica Miagrammopes oblongus Yoshida, 1982 – Taiwan, Japan Miagrammopes oblucus Chickering, 1968 – Jamaica Miagrammopes orientalis Bösenberg & Strand, 1906 – China, Korea, Taiwan, Japan Miagrammopes paraorientalis Dong, Zhu & Yoshida, 2005 – China Miagrammopes pinopus Chickering, 1968 – Virgin Is. Miagrammopes plumipes Kulczyński, 1911 – Indonesia (New Guinea) Miagrammopes poonaensis Tikader, 1971 – India Miagrammopes raffrayi Simon, 1881 – Tanzania (Zanzibar) Miagrammopes rimosus Simon, 1886 – Thailand, Vietnam Miagrammopes romitii Caporiacco, 1947 – Guyana Miagrammopes rubripes Mello-Leitão, 1949 – Brazil Miagrammopes rutundus Liang & Xu, 2021 – China Miagrammopes satpudaensis Rajoria, 2015 – India Miagrammopes scoparius Simon, 1892 – St. Vincent Miagrammopes sexpunctatus Simon, 1906 – India Miagrammopes similis Kulczyński, 1908 – Papua New Guinea Miagrammopes simus Chamberlin & Ivie, 1936 – Panama Miagrammopes singaporensis Kulczyński, 1908 – Singapore Miagrammopes spatulatus Dong, Yan, Zhu & Song, 2004 – China Miagrammopes sutherlandi Tikader, 1971 – India Miagrammopes thwaitesi O. Pickard-Cambridge, 1870 – India, Sri Lanka (type species) Miagrammopes tonatus Chickering, 1968 – Jamaica Miagrammopes trailli O. Pickard-Cambridge, 1882 – Brazil Miagrammopes uludusun Logunov, 2018 – Malaysia (Borneo) Miagrammopes unguliformis Dong, Yan, Zhu & Song, 2004 – China Miagrammopes unipus Chickering, 1968 – Panama Miagrammopes viridiventris Strand, 1911 – Indonesia (Kei Is.)

References