SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba450ee3bc8b17c79c105b32218c36b44fc73f2d7a10ade068c43d784028f517' 
  AND token = 'PYUsVgvqya6aXV0aCKw7VgIKckKTdt6jBZc/pRVNT+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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