SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a458da5b5b42575f11c444130a28d139b039033c7ff7806926f6943026112cf3' 
  AND token = 'EPIT8bXpPoezoBtdyP/NR/iFzjV0JCbuQMrb5tCaiLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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