SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92c385e7f94d5b883be36289e0dd45a5bf8c2c8c34ab66dd727b633bc482ba46' 
  AND token = 'N6VEHzHnHkpPZDDgv9vlpiKw/VUhJF2+7gDleTqsYOg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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