SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d4b22c06005ac1ed4125ee293f0b5152e5057e53310334ecd0d8b61d5a29555' 
  AND token = 'G6RnzYpv2wigMHyZyGe1WPtMaaAoTuWiixAEBruTixg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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