SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34aede220ea198bde169e0fd3985d830ceb328fe42ec063d3bba1cb1f7a35feb' 
  AND token = 'uPHWkPsi+bdpDWF/7cATTKRP5qZixBq7rtPxVdJcl4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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