SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '23f6dcbb823775f1ef480ef0165e6417fe254162aa7827d83991ee152b0a87ae' 
  AND token = 'Slbg9UyJhZKfo3LMZbjmZbOToEKCd/naGOSbar6Bvhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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