SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2d1ee27d6e11cba0f4186895473976ff41b071b33681f8c2f082769a8d221d7c' 
  AND token = 'kYBsr6mUnueSpJZVOkIavpHss0JZPQaGFPRtehqvVPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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