SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '953f5083d73d40c9a2b752ec406de9c52396a87f5b0899ab7dbe9ee635d57e6e' 
  AND token = 'KzjJY1mmXRGw3WUuOOLVplFDKA89LYxNcvROBcYEVhM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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