SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43abb344b313823cf86d7a156e1d4b9c02b3b26e790aa00e793e2fe64583194b' 
  AND token = 'yY+CLUJJgFW0AjzwVaWG5RkRLUjPrNlsuKo/dLa3pPA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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