SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf0cad63390c5c035b0275b4cbf85c38852bea3d0ada2436dfc6dfb220e3f662' 
  AND token = 'hddxEXSJi2RrwwUoDgA7hZmfq9odQ0VC+8xtagK1zwo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}