SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a75112d879abf0bd95501a78c87f34dcd87327395c61ad8748aa35a0e52a7904' 
  AND token = 'YyDDCFJZ+HGvO6VIavPuni/7pK0YTGg1WTNlYmdUoOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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