SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd1fede86af3f42f6b9caf916accbc18026d842febdfe8d0c16194b5bff77f100' 
  AND token = 'eoQLHHFskvQsAdT+Uepvk5jvK3EVsVHGLp/XY4qiWNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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