SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c430417f704dfca09a6a09bd246cca126e584c257bad848cbaa726e2af44c39f' 
  AND token = '2mUO4Z8HI0hbomsTWx+tQCnqMYwOSnmOBJm9leti8DE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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