SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92691f3c72e1fcc7a82d5c4542abe695ad9f91e44b621cadaa0485a6243f6c3d' 
  AND token = 'dVaBMFBDbsdF1QLnHdyFMD/Ojba65TinMuECncKlQrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}