SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05f94a7b3fe5c3b5f8a9a994f2056e5ff30b0124cd717498c2ea8a14cfbb4676' 
  AND token = 'tZjkKPTvnZJ3LKxXBe7xSa1gh3qUMbPT7zRjmd/1sV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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