SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7ff67fd027aceaa13a0fd148af5ae30633fdd6e4bc48bd56b99d25c0a8bc0691' 
  AND token = 'xHOo9ktmfLjhMeVZdFY4LKJjq+dvWgdKcdknYsaJ5cE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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