SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7aefba381a070c4c52e87c9715058aec130ede9bd921048eb251862d3616d7a3' 
  AND token = '13ca+yP6tTUD1RVSEE3xr+OU9QWnBr0F/T7vZEKNHlw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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