SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '904138b58ff6bf6c6db7ca21567a873e92713847c8713c455e66951356c16fff' 
  AND token = 'm0gSYzCB2REgxOvqTbMVYcn9Ka18Ilu1DWQlHlPCkyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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