SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e8c83de7379a835625b1f89cb7a5f559b48ffc6712b0d30a6518a484799162f' 
  AND token = 'risZaobdNGZkJVZ5XyQyHzqFL/fVRUmB3eQYdp5bcMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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