SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69bc1b997dfd4206d7798459e4fbb573a14b8e48f549a473b660c07e403f3d72' 
  AND token = 'lhP7w1wOwxahBa1jJGJbO8D7AFYvQo/V+sBLfNQ8q7c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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