SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c8a432d03d2af425a0056a4ce7b2314d3e1e81218c3fba121fa5c756e965aa8' 
  AND token = 'G28PtmOMlwYqFt8TjfC4vvCqQb56UBKVUX5rH8hvkz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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