SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '330c42856f9337dd17e09354b32e6003cc42163e540d4df01252fad4894fc4f4' 
  AND token = 'CkGi/ipJGv/86ymQqj4OzmunqGIcBX+8vP1ZVxSbJ28=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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