SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '833d55faf3fda72d4bf8722a41055ec08c1b3499d41077860240d9230bcb6b62' 
  AND token = 'B/W2mPPJrZ8XoNhKqn4it1M4/2P29eWEAAdRz4aZ0sU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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