SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecdadca7a86b54720e926a34b33c476bf424e4c47de2e08efbc5100fe5f3d141' 
  AND token = '+wxfUxB/jN/GGhxK31vstgNPUpLHf1GGjnq9/nGfJ08=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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