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Building upon three late-type galaxies in the Virgo cluster with both apredicted black hole mass of less than $\sim$10$^5$ M$_{\odot}$ and acentrally-located X-ray point-source, we reveal 11 more such galaxies, morethan tripling the number of active intermediate-mass black hole candidatesamong this population. Moreover, this amounts to a 36$\pm$8% X-ray detectionrate (despite the sometimes high, X-ray-absorbing, HI column densities),compared to just 10$\pm$5% for (the largely HI-free) dwarf early-type galaxiesin the Virgo cluster. The expected contribution of X-ray binaries from thegalaxies' inner field stars is negligible. Moreover, given that both the spiraland dwarf galaxies contain nuclear star clusters, the above inequality appearsto disfavor X-ray binaries in nuclear star clusters. The higher occupation, orrather detection, fraction among the spiral galaxies may instead reflect anenhanced cool gas/fuel supply and Eddington ratio. Indeed, four of the 11 newX-ray detections are associated with known LINERs or LINER/HII composites. Forall (four) of the new detections for which the X-ray flux was strong enough toestablish the spectral energy distribution in the Chandra band, it isconsistent with power-law spectra. Furthermore, the X-ray emission from thesource with the highest flux (NGC 4197: $L_X \approx 10^{40}$ erg s$^{-1}$)suggests a non-stellar-mass black hole if the X-ray spectrum corresponds to the`low/hard state'. Follow-up observations to further probe the black holemasses, and prospects for spatially resolving the gravitationalspheres-of-influence around intermediate-mass black holes, are reviewed in somedetail.

Central X-ray point-sources found to be abundant in low-mass, late-type galaxies predicted to contain an intermediate-mass black hole