SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59e06e6014878bebc6c657098ab8fedb855b07322f32805a5b1297f3d1e67855' 
  AND token = 'usJVDYd0u78YxnEOVsN9yg7DOwFSfe6ElM7+K7dxUK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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