SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f293220dca977efec61c375fb28ed5b5ca1d188ed8d8c50f1360eb5c6a553626' 
  AND token = 'KCgCzQ9zH/kVJfUWTx/nKMLHU6G5jpQYLG2KMwZBuSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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