SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd50bc47ef9ccf789f87e4fba2883e17af49391905323d2661f92b12cb88d8da2' 
  AND token = 'ffxlBZgRU/KCiPJ4LXIEzBmY5X7govmIfMHkh/Hr+O0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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