SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edd09b0d5c7382eabc10daffcd29cc298c0f42aad1f454fd5e37812ddc4651bf' 
  AND token = 'dpe0kYrIeVoCYVEw2SRjjbN3hij363aBpGYVKRsWgDQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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