SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '176247c96111d7ab3d78bb19e68f55101cb3fbf50b62cb1c9753c9b0b4346f4d' 
  AND token = 'h0BYrjJb/PdluCWMJiBpHUS5T6gvIvk8JX8K78EAgGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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