SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b153b60737f779bd4e9dbbd3da25b463656c432b0c85c02f7431e614ba2163cf' 
  AND token = 'ihBxnhzD9j0aY0RdfluCKLj2V342ZpZbaHCTFYLl+t8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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