SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd583d4406dc7971e4119553208e68b7af2d382573755dfe43d7ff9b832bf4fb1' 
  AND token = 'OJpTigjcQBXLHcMsc+tVhV5zPXkyntQrE0oH3TTLbjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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