SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3da95c60026395ea8bfeb2ac74d07dbebf1aba1c02d11113ee64885a24e58a74' 
  AND token = '1VQEGE17ei0b7qjkPkpb9pDtcL+a2glfN5ERmOp18GU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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