SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf761479dec8a7b87dbb76b80e54e2cf9ac92bf65ef76ce63a5fd448fc1565b5' 
  AND token = 'V42ZvzRyWF4dSoIvEvzWdc7JIY0ggMpxEZeeWv3kGgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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