SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '919154c35e01682382f312d5829041def0426bc375a29ae5df281aa91a2ef5e8' 
  AND token = '1xsv9COec7S2WPmQRzyO0csPM4Z8jDdYXOQRGrCYBBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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