SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5dad777faf14304b99ed4633cc0048d98f0aa7b3c9b7c98c56fa4f778ac7e080' 
  AND token = 'ZixVMKDTQDqsejJhRvVyVZ5WiAcL+2ZQiKvETp5hqds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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