SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd3854004dd62c778ea8f2470848e263e76bc666e47aa25559392ad75feb3217' 
  AND token = 'Ch0yhBL7mjPnZb1sVtqMWZu7c+M9Tev5/44u+4tzXgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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