SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '332b85c5c10b177fdf60d0d05673c7501c4da9be4c24659f5e7716764e01d644' 
  AND token = 'bphSCbr6mzCpGhaUseBsMG1nCCWzLioLQ+cQJEJpSzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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