SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b5bb63c1909a4f58158165057e80b1a52a56726b1b143ecf038896484286696' 
  AND token = 'XCEOthptLG/TWGgQPI4+wOFv27BS6oMGRarSqnaYyoY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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