SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0cad3b7ff1a2c3bd77edcb27849863d50c1e9ff04c023a915444f536537e69f' 
  AND token = '+YzeKdOSLxXjcq3F+N8qCBZsXmsGuOaouZ+YVaVBF68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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