SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5cd1392d059601abde7ace0d1794e7829673bfea9d6ce89b115f05f0e908dbf8' 
  AND token = 'zMq7T2VCjDBSMXHRBLB+oQaQ9NU/1oLv3m3Eznf73iw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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