SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '310a3e2f85e1f91487908bdd0ad367479e05805f4852710ff61b81192f2e16ff' 
  AND token = 'dF6klORoBnvAXYV0skH3Zmqy6XbAwRXviyAfL+3UzT0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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