SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8c6f06c38cb1343241fadb99e728bd26c0db2034384147eedd780ae1c5f02180' 
  AND token = '9IzfzBxmxqNmgUg/jienh0OKsT0juPGbZDoZGCbSmWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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