SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3ad0af016530e5ebd6c78282de4f6ec070e6b82be06aa18c6e2ebf88fc1e698' 
  AND token = 'KHXiweRibiEUUSWOq4fsR8hTGJN2Hx8XiictuyhzfDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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