SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f13c620bfd3264d7a526acc010f4b1fee035f4621abd0ae2b130ba62bd7ed21f' 
  AND token = '0qPIpzup3NbFj/NmlGhOXVCdFRW8rSJFvycCZY0oF/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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