SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eefc78acd0385934a80bbc6a655b6525bb10d3b386f56284d66fbc81d1f79b6c' 
  AND token = 'dlN8XtJtzFK1dnBrwG+EYB3QAXX2/pnzlEkvNKsmbIg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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