SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a67f678d3e26a1809569cf3bd71ae441f6e50c8071539d5b0613fd2db8c5190a' 
  AND token = 'FZnhBPdJaZKTbGJP/O/6SIRzwmVSX9PY3wmevTPMLWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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