SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'df2681b515d31b182cde0c875191a83c2c4d7df14e00ddf3753ed622f7a68678' 
  AND token = 'IRYJFxjIi1VSSxg5pEfe1ExPZvqcwWuX+Fr6uWlGiws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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