SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26295f5e5f67b145e16dd8c394d9d59d705a9708b8fa88fce079de94d3ce07f7' 
  AND token = 'nIpWqgTSx3iinuY7jhC4VHAB3QnRAHKY+NRmV0z5oJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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