SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0efdcbc995add99fd5e2c3e1e11cf9e9320d6d8b4158b28d3c40d7a48b781fbc' 
  AND token = 'r2hdoriXrMd3bbv9bXIdzwbV2GeWViKzd3UCfHriG2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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