SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d1b947407bc187f23c2141857ba979fde033f09acd9c7d9d0c560aac27712ea' 
  AND token = 'vyzMwM5tPEu46l2DueoreGmTwtAFKjZs5Ep1LbOZCRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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