SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5edb8abb0a060d0a826e36700e20b2aa18d161919f1ceb63730ef2057f179a97' 
  AND token = 'zMp+XwKjImlAhUwqLjN7R78XB0WNTNUSYbwWnPK8BUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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