SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33d91a20f836fe6a343a3c70bedcd240a2b0a84c47a702e724c577a6ff542af7' 
  AND token = 'YycPHZDhBCE8n0fxzvIttr2rcns165iUuR0b6vYPtWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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