SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '99376900e14bd8e63decad2042c46a9f3e356befd897803a3ff0b181f1bd7531' 
  AND token = 'czSeKgJBYj2y7RgH0D2irQ1zOLx2/DXKwPYuW3mgoqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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