SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32b54f11878237008414677a47c713bbeabcaee359fdd2839b407ecfcec55cb4' 
  AND token = 'N8dpsIxzTKjZ0sRGBLnyZ7pKtS3zzRcxkvcor63OU2A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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