SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '96e7069eb6db154b075aafeec01cdb41e2b10d6349645c01e2289f8b8ba6f0ae' 
  AND token = 'ui1XKKfi/O4JDQ7WZTzCkc948PBLVVwTRvCnHQ/jRhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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