SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb48143fec5a9245145a776864dc3bd891524d9938d0ed082c14ddee2293329e' 
  AND token = 'BBCwvvJTXCm1sah6RjqVGfzbwKPi3G3pw4qDmYQDwRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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