SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd075faf0baf0ae5e6a131392a6e377e364f32fffbc16342b85168216525ea02f' 
  AND token = 'YW4Vvs9PadNaEuuOMDwSHM/Oa7S/MbkPB6NzozRP9ug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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