SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b52a065b4143b3c666d6a345cb8a93db6ed27da8d17d0c775a1883091f5fc87' 
  AND token = 'T1uVfUejOYJqquztxnJRNYpUbz+J+UzepBlGg0fW6c0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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