SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6474d6babef73ed98043678f94f9e163cd6d4f3e5220584d40b84f2f42d12eb1' 
  AND token = 'lc7O5RsqurivfCQUgYiGx9zZGkHlLFKnaXyiBPzAjHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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