SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba3396011617a43f849dd5c4dd861bdf73ef6a631d33aeee4cafbf2c8aac43b1' 
  AND token = 'V4a4urLMWUs5/72LrdpoaUUDQzLxqJxDuMCX6aFVvHE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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