Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52d6fd03a2d462962d137a004d6ac130fee542a73b4ccb05ea25b6489dac5f28' 
  AND token = 'UpT8UeQ65TUH1NWQ7+mpB2K/LwdrQVHmc25sAgHIcKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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