SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d6d84dbb5ee203a87017ce8030030242f44ee44108c39bb93dd934b4f4456ed' 
  AND token = 'V2xy0dTeaK0iDc5VuXWzySvjpmNdguaViM/OCK/oX6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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