SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '20c452f2c4d91ab9cb8ce5ae913f23a78c8ba8f0985b1d11603f96d0c1ac067f' 
  AND token = 'ZV5HDVpBgMVBm06qhf4HTp0OUI3xcDxhQOUZrc+X12w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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