SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3b01983a8a2fd601a7f056549f005a20dcb0327182a5e78c9fd570216ed526a6' 
  AND token = 'vsANix06Q2BaDkmbaU8Y4ErPUUOhIeMlkgGntKSM6is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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