SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '33efcbfa0c59274ac8ebc47a36e928a048c396d1c6e4d985a5bc151962ffaf83' 
  AND token = 'K87esXUq11NqdYahwUK/qSSNt7mxF/3rCoxgszLMsyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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