SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c97a52eeb2fd648091877e099e2d68b47f36c8d5157a21768368d24c8d94f31' 
  AND token = 'Naqw/RuCCtT3IfwrZXSRE5AXymhkKgBYx6fCsipWIco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}