SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c617e0c8a31a7a4eb10b167e7f6be43b425f6992f18fa3f450f474ac2d0d3d0' 
  AND token = 'IjLxPZabO4q6sZMpQGg+J58OD7hHu73ZuwOhWG0x/as=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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