SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c604add3bfa1f501ddcc37589a74fe63dcfdba7e7c18228142e855c36c88f06' 
  AND token = 'uHM5vEHplB+6FXis+QFzUYd/6rRAeC/PIfRLBYwUPpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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