SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '031d6a1f867494589244d5569f5631fd293285c55d58b53c79595826ec2224ef' 
  AND token = 'v0hqQQpUQpETMHSCAhVLFGA31crgYqYYz70HTOr99Zo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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