SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd6b7262f4fb01f461b011da8568faa57a80c919a75add5ff598e7ab853c5b40c' 
  AND token = 'RXSYSz3egCztstEEmfhGAvyuDH60y6oNQlFq4Z5W7gc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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