SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b955f54a9951d106466b4b787cec122b3cd5b5cab7478064ec06683485a0d8fa' 
  AND token = 'Rxq3q5hg6B8QP7nWYLuTF6FLN0xwkVOOozjT+XKzxLg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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