SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef80f25449cf1f738bb5a715a109bfad8265a675d2ef31b8b084c873f7904c5c' 
  AND token = 'TFFCIMJm14xmxZhEP1NKdWLYHOKQg+5yOu6whdkw4jc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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