SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47e2f828d7b09488e880e78f8268ca5a9c896a36cbb808e4d1886eb2d4fc1007' 
  AND token = 'KFY5Y3wxJVl1AcwDwTbhGTt9du+BcL+VWbdDeH7ijLg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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