SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ac0ffd5dd8e71d12397f5ddd33fce98ccbbffbc119ea295ae915fa983696a30' 
  AND token = 'twKDaE4YEuhVU5lPcmaAAeP6wP26+k7RZXT49ncr5ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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