SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bebc3f033de4d6e51309b4aad479366648fe4c5b42c5d4bb8a0678aef0fa968' 
  AND token = 'kqib6bpdb3Q6HD2nNi2bswhkc10rZidTGWZR43lXRh8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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