SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16bb9933601984428164dbd845110e72587c402f8a54823ceb541829f80fb701' 
  AND token = '2r1L6we9L87tLEJsXrQQGp/hG8HnLRcMFOl43loZoZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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