SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a1409dff35e7927541fced36a5059b03ad3683b79ac43fe1fc6a9a44d550f3a1' 
  AND token = '6eHdx37O0/TzfEiclacroGQVzJg0cgM2trS2tv5Nlh8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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