SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fd347c6b5f8fc2635b13fa0cf45d039b3b9c3fbf887d2f03f8fed7be72e44d2a' 
  AND token = '1q/KAWWwy5jV3gaRSOklaD4I6xFhWq8wH976jYluI9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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