Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdefe8212f13661b900059b6fb1d8d30feb0f978ae03c8d5aeb57a40f0ce2c8f' 
  AND token = 'FDVpKp8Q0PoY2QZkYwZEGQ+TFdelzyR/grdJVYJiT+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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