SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'db373cb9b0ac733d2638ce68fdad4824dcbe490801c40cc5f1bef35a6151f97e' 
  AND token = 'Cyj7m6XHI0F1W1ZRpYW/ySmhTTrGEnUCNQNdLiyC6Y8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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