SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7c4af6f5a7081eae3607296c33cae1712b84ee3341e5dafa2e40b0e51bcac0fe' 
  AND token = 'mlAq9XtfcU0kQpawe0NgiqaW4ncwlcr0PsXYunmqFxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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