SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04ba91042fbb03c238e109c42bd0bf48c79f30e2ca7fb809cc9bc9edba0f9a98' 
  AND token = 'zUTrzthBIoamZvB/kr0VSwwAs4jGfzLEaXgmCOCUNKk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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