SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f81d89b8855711170235efa78393e9a7f51b096c58290662e1cbb2716be7b3b' 
  AND token = 'tN+SLXvVfal2Xo4ft5HdkYx5LRJYKZPieNZH3VGnnC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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