SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ef664a8ba5cbea5b4cdd3d34a7c50bfa12936ac60d274d3b35927d66f8dbfb1' 
  AND token = 'IVC2E5u6fqMUhJHR9Ta/QS0w/LDWPj2qIHzePeBqSFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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