SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a4a385c4a6e3f7821bd0051b8710cfcbd2dd7e1f1b076e818f817c33ff8657f5' 
  AND token = 'yRizRAnZCTH2JGFZ/2y6ZNg+WqKQaY00RqR7TWjHuY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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