SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e5cb5f10255e9f424f85e25b06590efd6b97e0c961ff17d84164aa2f8b68096' 
  AND token = 'LWXHCCuqJqn002QNdDK6Izay4CTGGLIddCgxzcNfENc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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