SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33c090b66a9467e01a1f812b4002722b421a98922bf589a2575d0caba7407b14' 
  AND token = 'TNeXCeTb7ViWQUcPcIkwpLXyKqLVYKpFBvAdzEjUsdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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