SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bff2f8b901416fefe2499354055231699fd01425766e259e5fedbbcad490cc62' 
  AND token = 'ItCDF+ZVmWIITrDri2WxyzDbXYW5UIiS00r/hFZN8XI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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