SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dddd9a17aa94523e7e68d2c4d81120342068eda54b3b0db0bb3172c754d5872d' 
  AND token = '9mC+3mxd0VlPI1dpqVTgZ9Tff4HuQMD/HdmAfcByBrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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