SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bb10180a2ec6d0d53c119655310b3d56d2d1dc3c9e882840aa93956d03ee3d3' 
  AND token = 'YBBLYlUrokdRE0pNlgEd8nnpOKmLyjwGgwepj2fXMqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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