SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbd2cbde8eabe973509fb7466eedb02c9fefb11c76f88595352bf23f8ffd0f29' 
  AND token = 'IdubAiWNu/VEVOdcgyh/UIcYBkGP9RYgluanWT1Lyac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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