SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8d6f06db48c124a0c4a075b1609da56266d52021a90818ee600ac85cfb67afa' 
  AND token = 'Xl0LguHtxtGBsVrOySjHfIBfXyGgiGC+LZxFWrdY1ZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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