SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cc2f3b80c31926fa26f4b82a831a25e94d5f3ae3c01c1165348c4077b73f1a7' 
  AND token = '0N5wYXZhHlVGcVboJk+MivqlSo31ERrhbiDgQVQDjDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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