SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2cc38132394b0f46c4c5d02bd43c994b631742babf5fd0151d9da70c46f036ab' 
  AND token = '9RHaaRXyU62ENkQQwbHSqk/L3nCsvFPOZskCfalr0yU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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