SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49a130a989d278a08e37582000c84aca48849c0b3f8045c8914113dad03eb1f0' 
  AND token = 'AYHs0H9ussc1ZykXpkkP5yLo+TUhUkDes2VHXjew3lQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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