SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33205bd1f8646aaa1411a6d993647293d3af44c1a82231b1e357a185e7a68c6e' 
  AND token = 'Gnsp8ymGP3qwEvg4cXk+CZRPHltK+ch70JEr0N845Ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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