SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '469d17b86077b9222b68899ede767cba4107e4bc23f47fec98815f71d7013ecf' 
  AND token = 'FoaifvzziCiW7NseFOfxDlQHBZ+lbDbWuyxUoUVVaak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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