SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ea10ad527209d2ee02b021b295be8df3e958d8be8efe5ec38c17d55b44b95f62' 
  AND token = '83FMW5FuAwnPUoa6yNAou6icWPHy8FfGQ1UgjcjJVWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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