SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31c307b0740f31a1470b05620209e78fb5ee4a660c50be95c02df366dd7259f7' 
  AND token = 'rmhSVYdOpnxkoSKNV3d68YtfWoW/dwWxJLb6E9FdnWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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