SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7e0d0201bf0422c56b37970c97c77841644e07aefeeeaae60df11f0ab5e440e' 
  AND token = 'V26NY8FpmtVEfCkwl80sSvWIzE0HN/iBVqSnXuk5xdw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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