SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4c8522976a9c1c5dab63c6f540fa0406023a4df1764739f7260db249e6454122' 
  AND token = 'AS1ZXklfV/7sjFnb9weFQYNK+GTal62kjaDV5E0NN3U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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