SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70d49fdecda14188838966e57fea8d9e802252a6f303f8a77f45e67648f0d88d' 
  AND token = 'KP6CK71iMr0gLqVLLoFu1HSnhtEA5zYxhxXlQdzgz98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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