SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5840f5e34043e60aa35e326153053827dc8def64bc691c1c07000c017bd36546' 
  AND token = 'j6q8z7DSYq49L8JwDJIQaX0c/gJfmlxUklWa/5Lxjns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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