SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c082f2069151af3860a3ba6a28a6d658935b552404b5bfb9faeac31cbaf98eaf' 
  AND token = 'q3WPkIy+CSvDq19Otu8r5+c8d57sTMbXrWAauKC88GQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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