SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd60fe67516ab22e96ba25a608bdf481c0971332fc776ee4652c9f1ffb36dce2b' 
  AND token = '9Owv3w7uFq6RmUV290aFj0wSRrEGYmv4rvbY05DuvlI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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