SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0de9db9bc428fbb3c471c292e24722aa95e717592a34365c931c089d8517a2b1' 
  AND token = 'q5JVw4PPqa5nf60jeOd9HGMqy+wWOgsAG96G0ZKnQvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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