SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c082951eb2d3d5e9c176a8d60e1dd1b07ada62df2c962503b050c740bc75bc4' 
  AND token = 'CSNwO36WtvLXN8SJiIHtrzUetz8f44qAl8Ac0bwvNbs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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