Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6c900267a42e4a4077a18da1e5d27beb300be9c483a6c14c4b175115e9b264e' 
  AND token = 'CMQnAw0ims++XsiEn7OvDMFgW2O/xHF53lmVH8+r8jQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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