SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5bbee1e66daf7bf51715e42cb6654ff4da0896a58a52f49583b69a4bdf7184c0' 
  AND token = 'KQ7EwudIMtg60LAeMIstaJvQ8ZUU2Wl+i4RyJuM4/v0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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