SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b635f00a99034242f3e33b7de1d965a7f744760cb2c277dd78f88a1f32dc7f0f' 
  AND token = 'KPLsHq4r8S/M7uzFM2XffTBSiQpmj3BhPT5hbUpBQHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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