SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2f6924b3a7785f3b4b5b0640b5653d58f37094398178278b9ea547343d6443f' 
  AND token = 'xWdvhGLwJRU2G9HE2BN9PPwoq6XiLgfxfwrfVm7FD8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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