SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e2baf996f2849b9a8c8edc060b796d4ae58f07c1712685befb0f80faf54551c' 
  AND token = 'H/Npsydb8/Q1GuSZkczOvXF1ZvFHHIHQOUtGgTj9i3E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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