SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24d341000c1c7cbb5320eab4f3babd0f12425311f69882a092cdc39ddefd2449' 
  AND token = 'ycM3tAv/GFZl43Wfb3mt1EAobRIZXVaTkElIf+I+gwk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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