SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd89411788c8d949bea8d54b5a2f356c316f7b07b5d8475bd0d28aca69a39ebee' 
  AND token = '64VkAu8xDuvyrzzKKhJwEo9mYxbpbZ5YGADzD+XIZ5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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