SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '472abdc756058cb1d9b42cdd26dbf353ab710ca4fa3c6ef81714831d44a8708f' 
  AND token = 'PuMViDlQhsaFdhGwJ1KZgxGVnMtG/bJqWvJ/8I0QmvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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