SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30e27b4aa94d4bd1cd24cd4e13148cb86d3f33c79bfc877e5e96821f7239afc9' 
  AND token = 'BpwHCQhGpIIYDr6U097bufrxPIZVQxjXC7nSasCRGts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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