SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '385376217cb3e3be6280a7243a4cf2bb2675cc1f0416d3ab721f25a0a7f8461a' 
  AND token = '9tINiJquMztYPd46zlvwzahUKKue59FJsc0CwIWZSQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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