SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32017bc4517a3883946f8f046a10cdb84954e236323bef20350e69a23e94226d' 
  AND token = 'DyXma/A5LnFzREbpTqIt/szhTxFvc5/VNkxHyqDX5v8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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