SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '470eb28a5db9f317da34fe281ee12d0ed7f459a2552cc6e517b94bdb07ca57fe' 
  AND token = 'dejqKfTfYE5Efyu8jKaY463+DKXVTMKW1OBGYaBkTXA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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