SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'beab07f3cf401f606c823e58f901bbb57249c59587e3f365b157071f93207517' 
  AND token = 'p4DznSeWMeUHcECTVbXUZzzTqYFoOqt+BPbRFUhmPCs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}