SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4357a2b9b49055b7d3f4419031116cfdbc43585cb2f69e73d875e7ecf42663a9' 
  AND token = 'Y9EBlLViw9rrzt8MR6JGT1hbU/phH7EonDbit8PLxZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00418

JSON explain

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