SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3641350ffc01201144a34064246080194c8e6650d95085e223fbb24db585b311' 
  AND token = '3XDpPYwHuu8ur4yx9FlLduKjOHk+5D2r5YRt0BfQNhs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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